Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1995-1999  (894)
  • 1900-1904
  • 1995  (894)
  • Inorganic Chemistry  (567)
  • Genetics  (327)
  • Industrial Chemistry
  • Nuclear reactions
Source
Material
Years
  • 1995-1999  (894)
  • 1900-1904
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Characterization of Japanese families with early-onset type 2 (non-insulin dependent) diabetes mellitus and screening for mutations in the glucokinase and mitochondrial tRNALeu(UUR) genes (1995)
    Springer
    Acta diabetologica 32 (1995), S. 17-22 
    Details
    ISSN: 1432-5233
    Keywords: Maturity-onset diabetes of the young (MODY) ; Genetics ; Diabetes mellitus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Genetic linkage studies of families with earlyonset type 2 diabetes have facilitated the identification of diabetes-susceptibility genes. In order to assess the feasibility of using linkage approaches to identify genes responsible for the development of type 2 diabetes in Japanese subjects, we examined our clinical records for multigenerational families suitable for genetic studies. We identified 16 families in which at least one subject was diagnosed with type 2 diabetes before 25 years of age. Seven of these families had a pattern of inheritance consistent with a diagnosis of maturity-onset diabetes of the young (MODY) and nine families showed a complex pattern of inheritance of type 2 diabetes with transmission of diabetes-susceptibility genes from both parents. The glucokinase and mitochondrial tRNALeu(UUR) genes were screened for mutations in at least one affected subject from each family in order to assess the contribution of mutations in these genes to the development of the diabetes. No mutations were found, which suggests that the diabetes in these families resulted from mutations in other genes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00581039
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Identification of genomic regions affecting plant height in sorghum and maize (1995)
    Springer
    Theoretical and applied genetics 90 (1995), S. 380-388 
    Details
    ISSN: 1432-2242
    Keywords: Genetics ; Breeding ; Sorghum bicolor Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The objective of this study was to use restriction fragment length polymorphisms (RFLPs) to determine the genetic location and effects of genomic regions controlling plant height in sorghum. F2 plants (152) from the cross CK60 x PI229828 were used. Genomic and cDNA clones (106) identified 111 loci distributed among ten linkage groups covering 1299 cM. Interval mapping identified four regions, each in a separate linkage group. These regions may correspond to loci (dw) previously identified by alleles with qualitative effects. Also, these regions identified in sorghum may be orthologous to those previously reported for plant height in maize. Gene effects and gene action varied among genomic regions. In each region, PI229828 alleles resulted in increased plant height. Each region accounted for 9.2–28.7% of the phenotypic variation. Positive, additive effects ranged from 15 to 32cm. Tallness was dominant or overdominant and conferred by alleles from PI229828 for three quantitative trait loci (QTL). At the fourth QTL, PI229828 contributed to increased plant height, but short stature was partially dominant. One digenic interaction was significant. The presence of a PI229828 allele at one region diminished the effects of the other region. A multiple model indicated that these four regions collectively accounted for 63.4% of the total phenotypic variation. The utility of this information for germplasm conversion through backcross breeding is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221980
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Mixed desmoplastic primitive neuroepithelial tumor of infancy: a light microscopic, immunocytochemical, ultrastructural and genetic study (1995)
    Springer
    Acta neuropathologica 89 (1995), S. 99-104 
    Details
    ISSN: 1432-0533
    Keywords: Primitive neuroepithelial tumor ; Desmoplastic small cell tumor ; Brain tumor of infancy Immunocytochemistry ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We describe a case of a desmoplastic brain tumor which was initially resected from the right fronto-temporal region in a 2 year-old boy. This nodular, calcified tumor was vascularized by the internal carotid artery and the middle meningeal artery branches. Grossly, it contained several mucoid cysts. Light microscopy showed cords or nests of small cuboidal cells surrounded by a loose connective tissue and desmoplasic areas containing fibers and spindle cells. The cuboidal cells expressed epithelial, neuronal and neuroendocrine markers. Some foci of spindle cells showed glial differentiation. The tumor recurred 16 months later and displayed some characteristics of the small cell neuroepithelial component, mitoses being conspicuous. Electron microscopy revealed undifferentiated clear cells, some containing neurosecretory granules. Karyotyping demonstrated the following formula: 〈 15 〉 46, t(8;11) (a13; q11). The chromosome 11 breakpoint was different from that described in Ewing's sarcoma. This isolated translocation has not been previously reported to our knowledge. These unusual features lead us to report this case and to discuss its pathogenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00294266
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Fetal brain disruption sequence in sisters (1995)
    Springer
    European journal of pediatrics 154 (1995), S. 654-657 
    Details
    ISSN: 1432-1076
    Keywords: Key words Fetal development ; Brain diseases ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report two female siblings with the fetal brain disruption sequence. Extensive investigation of both children failed to define a definitive aetiology but clinical and laboratory findings are consistent with a hitherto unknown storage disease. We postulate that the accumulation of a neurotoxic metabolite may be responsible for the disease phenotype observed. This is the first report of recurrence of the fetal brain disruption sequence and supports the existence of a genetic form of this condition. Previous reports have emphasized possible environmental aetiologies. Infants with fetal brain disruption sequence should be investigated exhaustively and, in the absence of definitive evidence of an environmental cause, the possibility of a genetic aetiology should be considered. In some families the recurrence risk may be as high as one in four.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004310050366
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Floating-Harbor syndrome: description of a further patient, review of the literature, and suggestion of autosomal dominant inheritance (1995)
    Springer
    European journal of pediatrics 154 (1995), S. 658-661 
    Details
    ISSN: 1432-1076
    Keywords: Key words Floating-Harbor ; syndrome ; Growth retardation ; Dysmorphology ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The Floating-Harbor syndrome is a growth retardation syndrome with delayed bone age, speech development, and typical facial features. The face is triangular with deep-set eyes, long eyelashes, bulbous nose, wide columella, short philtrum, and thin lips. We present an additional patient and review 16 cases from the literature. The possible phenotype in the patient's mother suggests a dominant mode of inheritance for the syndrome. Conclusion The Floating Harbor syndrome is a growth deficiency syndrome characterized by proportionate short stature, characteristic face and delayed speech development. Inheritance is possibly autosomal dominant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004310050367
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Genetic counselling on brittle grounds: recurring osteogenesis imperfecta due to parental mosaicism for a dominant mutation (1995)
    Springer
    European journal of pediatrics 154 (1995), S. 123-129 
    Details
    ISSN: 1432-1076
    Keywords: Key words Osteogenesis imperfecta ; Collagen I ; Mosaicism ; Genetics ; Recurrence risk
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Osteogenesis imperfecta (OI), a dominantly inherited connective tissue disorder, is usually caused by defects in collagen I. There is growing evidence for parental mosaicism that results in affected children born to unaffected parents. This situation poses a difficult task for the geneticist because a mosaic parent may appear clinically healthy while carrying the mutation in a fraction of her or his gonadal cells. To illustrate this problem, we report a Swiss couple whose first child was affected with severe OI. The unexpected recurrence of the disorder in the second child raised the suspicion of a recessive trait or, rather, of parental mosaicism. We identified the responsible collagen mutation in the COL1A2 gene (Gly688Ser in the α2(I)-chain) in both children and demonstrated the father to be a somatic mosaic for this mutation and to have subtle clinical signs such as soft skin and short stature that may be a result of his mosaic state.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004310050261
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Fetal brain disruption sequence in sisters (1995)
    Springer
    European journal of pediatrics 154 (1995), S. 654-657 
    Details
    ISSN: 1432-1076
    Keywords: Fetal development ; Brain diseases ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report two female siblings with the fetal brain disruption sequence. Extensive investigation of both children failed to define a definitive aetiology but clinical and laboratory findings are consistent with a hitherto unknown storage disease. We postulate that the accumulation of a neurotoxic metabolite may be responsible for the disease phenotype observed. This is the first report of recurrence of the fetal brain disruption sequence and supports the existence of a genetic form of this condition. Previous reports have emphasized possible environmental aetiologies. Infants with fetal brain disruption sequence should be investigated exhaustively and, in the absence of definitive evidence of an environmental cause, the possibility of a genetic aetiology should be considered. In some families the recurrence risk may be as high as one in four.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02079071
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Floating-Harbor syndrome: description of a further patient, review of the literature, and suggestion of autosomal dominant inheritance (1995)
    Springer
    European journal of pediatrics 154 (1995), S. 658-661 
    Details
    ISSN: 1432-1076
    Keywords: Floating-Harbor syndrome ; Growth retardation ; Dysmorphology ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Abstract The Floating-Harbor syndrome is a growth retardation syndrome with delayed bone age, speech development, and typical facial features. The face is triangular with deep-set eyes, long eyelashes, bulbous nose, wide columella, short philtrum, and thin lips. We present an additional patient and review 16 cases from the literature. The possible phenotype in the patient's mother suggests a dominant mode of inheritance for the syndrome. Conclusion The Floating Harbor syndrome is a growth deficiency syndrome characterized by proportionate short stature, characteristic face and delayed speech development. Inheritance is possibly autosomal dominant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02079072
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Genetische Faktoren bei der Entstehung und Progression maligner Melanome (1995)
    Springer
    Der Hautarzt 46 (1995), S. 394-399 
    Details
    ISSN: 1432-1173
    Keywords: Schlüsselwörter Malignes Melanom ; Genetische Instabilität ; Genetik ; Syndrom der dysplastischen Nävi ; Xeroderma pigmentosum ; Key words Malignant melanoma ; Genetic instability ; Genetics ; Dysplastic nevus syndrome ; Xeroderma pigmentosum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Exposure of the skin to ultraviolet irradiation is an important risk factor for the development of malignant melanoma, with UVA possibly playing an important role. Hereditary factors are also relevant. In the dysplastic nevus syndrome a genetic instability has been shown by different methods. In xeroderma pigmentosum the DNA repair defect is thought to be responsible for the high incidence of malignant melanoma. Frequent and non-random changes in certain chromosomes have been demonstrated in melanoma cells. These might contain sequences that control melanoma growth or melanoma suppressor genes. Especially the short arm of chromosome 9 is thought to contain one of these genes. This hypothesis is supported by a genetic linkage analysis in melanoma families and the demonstration of a germ line deletion of the locus 9p21 in a patient with eight primary melanomas. Changes in known tumor suppressor genes and oncogenes have also been reported in melanoma, but no consistent sequence of genetic events is known.
    Notes: Zusammenfassung Die Exposition der Haut mit ultravioletten Strahlen ist ein wichtiger Risikofaktor für die Entwicklung eines malignen Melanoms. Möglicherweise spielt hierbei UVA-A eine besondere Rolle. Daneben sind hereditäre Faktoren von Bedeutung. Während beim Syndrom der dysplastischen Nävi eine genetische Instabilität mit verschiedenen Methoden nachgewiesen wurde, wird bei Xeroderma pigmentosum der DNA-Reparaturdefekt für die hohe Melanominzidenz verantwortlich gemacht. In Melanomzellen sind überzufällig häufig karyotypische Veränderungen in bestimmten Chromosomen gefunden worden. Diese enthalten möglicherweise Melanomwachstumsregulierende Sequenzen oder Melanom-Suppressorgene. Insbesondere der kurze Arm des Chromosoms 9 steht in Verdacht, eines dieser Gene zu enthalten. Diese Hypothese wird auch unterstützt durch eine genetische Kopplungsanalyse an Melanomfamilien und dem Nachweis einer Keimbahndeletion des Lokus 9p21 bei einer Patientin mit 8 primären Melanomen. Veränderungen an bereits bekannten Tumorsuppressorgenen oder Onkogenen sind ebenfalls in Melanomen beschrieben worden, ohne daß jedoch eine konsistente Reihenfolge von genetischen Ereignissen bekannt wäre.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001050050272
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Allelic relationships between genes for resistance to tomato spotted wilt tospovirus in Capsicum chinense (1995)
    Springer
    Theoretical and applied genetics 90 (1995), S. 146-149 
    Details
    ISSN: 1432-2242
    Keywords: Capsicum chinense ; Resistance gene ; Genetics ; Pepper ; Tomato spotted wilt virus ; Tospoviruses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Pepper (Capsicum chinense Jacq.) has been reported to be an important reservoir of resistance genes to tomato spotted wilt virus (TSWV). The genes for TSWV resistance present in three C. chinense lines (‘PI 152225’, ‘PI 159236’ and ‘Panca’) were investigated for allelism. All resistant lines were crossed with each other. Parents, F1, backcrosses and F2 populations (including reciprocals) developed from those crosses were mechanically inoculated with a highly virulent TSWV isolate. Susceptible C. annuum cv ‘Magda’ was used to check inoculum virulence. Fifty plants of the F1 hybrids; ‘Magda’ x ‘PI 152225’, ‘Magda’ x ‘PI 159236’, and ‘Magda’ x 'Panca, were also inoculated with the TSWV isolate. The resistance response in all C. chinense sources was associated with a localized, hypersensitive-like reaction that was phenotypically expressed as a prompt formation of large local lesions accompanied by premature leaf abscission. All F1 generations presented a final score of resistant; indicating that the expression of resistance to TSWV is conditioned by a dominant gene regardless of the source. The absence of segregation for resistance to TSWV that was observed in all generations of the crosses between C. chinense lines indicated that either a tightly linked group of genes exists or that the resistance is governed by the same single major gene (probably the already described Tsw gene). Previous reports have indicated that the Tsw gene is not effective against tospovirus members of serogroup II, i.e. tomato chlorotic spot virus (TCSV) and groundnut ring spot virus (GRSV). In the assay described here, all of the C. chinense lines showed, after mechanical inoculation, an identical susceptibility response to the TCSV and GRSV isolates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00221009
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Diallel analysis for mineral element absorption in tropical adapted soybeans [Glycine max (L.) Merrill] (1995)
    Springer
    Theoretical and applied genetics 90 (1995), S. 707-713 
    Details
    ISSN: 1432-2242
    Keywords: Mineral stress ; Nutrient efficiency ; Aluminium tolerance ; Inheritance ; Genetics ; Breeding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Brazilian tropical adapted soybeans contains, in addition to superior morphological characters, genetic factors for tolerance to cultivation in acidic, mineral-stressed soils. However, the selection process for these hindrances has been empirical, and information on the genetics of mineral element uptake by the plant is necessary. The objective of this investigation was to identify the mode of inheritance for the absorption of phosphorus, potassium, calcium, magnesium, iron, aluminium, manganese, zinc and copper in a 9 × 9 diallel cross. General combining ability (GCA) was higher than specific combining ability (SCA), with the exception of copper, manganese and zinc, indicating predominantly additive effects. The ratios of GCA/SCA varied between 3.4 (calcium) and 8.5 (magnesium). The regression of covariance (Wr) on variance (Vr) showed that the additive-dominance model explained the genetic differences in this germ plasm. However, the detection of overdominance could be related to possible heterozygosity in the parental varieties for mineral absorption. Broad-sense heritability values were higher than narrow sense heritability values for aluminium, iron, potassium, calcium and magnesium, being in the range of 67.9–86.9% and 42.0–56.6%, respectively. This is an indication that soybeans can be further improved to efficient utilisation of nutrients and to tolerate toxic factors in the soil.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222137
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Opioid operant self-administration, analgesia, stimulation and respiratory depression inμ-deficient mice (1995)
    Springer
    Psychopharmacology 117 (1995), S. 23-31 
    Details
    ISSN: 1432-2072
    Keywords: Opioid ; Genetics ; Self-administration ; CXBK/ByJ ; Reinforcement
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract It is commonly thought thatμ-receptors play an important role in the reinforcing effects of opioids. In the present study, inbred strains widely divergent in CNS opiate receptor densities were used to investigate the influence of genetic variation in receptor concentration on opioid-reinforced behavior. In particular, the CXBK/ByJ mice were used as an investigative tool because of their significantly lower number of CNSμ opioid receptors. The behavioral pharmacology of opioids in theμ-deficient CXBK/ByJ mice was compared to other commonly used inbred mouse strains, C57BL/6J and BALB/cJ, and the opiate receptor rich CXBH/ByJ mice. Operant opioid reinforced behavior, opioid-induced locomotor stimulation, analgesia and respiratory depression were investigated in all four inbred strains. To assess the acquisition and maintenance of opioid reinforced behavior, oral self-administration of the potent benzimidazole opioid, etonitazene, was determined using an operant fixed-ratio schedule of reinforcement (FR 8). Acquisition of etonitazene-reinforced behavior was established in all four strains including theμ-deficient CXBK/ByJ mice. However, there were significant genetic differences in the amount of drug intake during the maintenance of opioid-reinforced behavior and extinction behavior following vehicle substitution. For example, drug intake was significantly greater in the BK versus BH mice during the maintenance phase and an extinction burst was seen in the BH but not the BK mice following vehicle substitution. Thus,μ-receptor density may not account for individual variability in the acquisition of opioid-reinforced behavior under these conditions. Sensitivity to etonitazene-induced respiratory depression, stimulation of locomotor activity and analgesia were unrelated to drug intake during self-administration sessions across these four inbred strains. These data indicate that inherited differences in CNSμ-opiate receptor concentrations do not affect acquisition of etonitazene-reinforced behavior.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02245094
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Chromosomal mapping of loci influencing sensitivity to cocaine-induced seizures in BXD recombinant inbred strains of mice (1995)
    Springer
    Psychopharmacology 117 (1995), S. 62-66 
    Details
    ISSN: 1432-2072
    Keywords: Cocaine ; Quantitative trait loci ; Seizure ; Recombinant inbred strains ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Among inbred mice, genetic factors mediate differences in sensitivity to the convulsant properties of cocaine; however, the gene(s) underlying cocaine's effects have not been identified. To help elucidate the gene(s) responsible for cocaine seizure susceptibility, we used recombinant inbred-quantitative trait loci (RI-QTL) analyses to identify chromosomal loci associated with cocaine-induced seizures. RI-QTL analyses seek to identify associations between a quantitative measure of a particular phenotype and one or more previously mapped marker genes across a panel of RI strains. This report describes an RI-QTL analysis of cocaine seizure susceptibility among 26 BXD RI strains. These strains showed a skewed, bimodal range of seizure susceptibility which could be the result of one or more modifying genes acting in concert with a major gene to influence cocaine sensitivity. Correlating the percent seizures displayed by each strain following 60 mg/kg cocaine with chromosomal marker data for these strains revealed a number of significant correlations clustered in two regions on chromosomes 12 and 6. This is the first identification of putative chromosomal loci associated with a cocaine-related phenotype and should facilitate identification of the gene(s) underlying cocaine toxicity and other cocaine-related phenotypes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02245099
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Sex segregation ratio and gender expression in the genus Actinidia (1995)
    Springer
    Sexual plant reproduction 8 (1995), S. 129-132 
    Details
    ISSN: 1432-2145
    Keywords: Sex control ; Disomic segregation ; Dioecy Kiwifruit ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The sex segregation ratio was checked in bi-parental families of Actinidia deliciosa (2n=6x=174) obtained by crossing four females (A12, Mo3, Br4, Hw1) with two males (T2, M1) and one fruiting male (M3h, subandroecious) according to a factorial mating design. The M3h fruiting male was also selfed. The sex ratio was checked in maternal families of A. kolomikta (2n=2x) and A. chinensis (2n=2x) as well as in A. deliciosa. Seedlings of both diploid species took 3–4 years to progress beyond juvenility, whereas a noticeable number of seedlings from biparental crosses of A. deliciosa involving A12 and Hw1 as seed parents were still non-flowering after seven growing seasons. Open-pollinated families of both diploid and hexaploid species as well as most families from biparental crosses showed a sex segregation ratio approaching 1∶1. Subandroecious lines with different degrees of ovary and pistil development appeared in proportions of 0–4.2%, depending on the cross, but only 6 of the 2567 male vines checked were capable of setting fruit. No case of self-fertility or apomixis was detected among 1866 bagged female vines. Selfed M3h progenies gave only female and male phenotypes in a ratio of 1 female to 3 males. No off-type vines were found among these progenies. The same disomic sex segregation ratio seems to be operating at different ploidy levels in the genus Actinidia. Since selfed fruiting males produced both female and male individuals, the male sex appears to be the heterogametic one. Such evidence indicates that a monofactorial system based on one or more linked genes or on an X/Y chromosome set must be controlling sex expression. How a monofactorial sex-determining mechanism could operate in polyploids to give a 1∶1 female: male ratio is discussed. Minor modifying gene(s) seem to be responsible for the feminization of males, and their expression appears enhanced by environmental conditions. Masculinizing gene(s) seem to be lacking in female genotypes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00242255
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Genetic mapping of adrenergic receptor genes in humans (1995)
    Springer
    Journal of molecular medicine 73 (1995), S. 299-306 
    Details
    ISSN: 1432-1440
    Keywords: Adrenergic receptors ; Human genetics ; Restriction fragment length polymorphism ; Chromosome mapping ; Linkage ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have genetically mapped the genes encoding four human adrenergic receptors (ARs) of subtypes α1C, α2A, α2B, and β1, which are prototypic G protein coupled receptors that mediate the physiological effects of neurotransmitters, hormones, and drugs. We placed these genes onto the Cooperative Human Linkage Center (CHLC) and Genethon framework maps, within confidence intervals with greater than 1000∶1 odds. With multipoint analysis the α1C gene (locus ADRA1C) mapped to the interval between NEFL and D8S283; α2-C4, the gene encoding the α2C AR (locus ADRA2C), mapped to the interval between D4S126 and D4S62; and the α2-C10 (α2A AR)/β1 haplotype (loci ADRA2A/ ADRB1) mapped to the interval between D10S259 and D10S187. A fifth AR gene, β2, yielded significant LOD scores with markers on the long arm of chromosome 5; however, this locus (ADRB2) could not be mapped to any specific interval with odds of greater than 1000∶1. The two AR genes that are completely linked, α2-C10 and β1, were oriented on their shared 225-kb genomic fragment relative to the direction of transcription, with β1 being 5′ to α2-C10. The positioning of these genes on high-density framework maps allows them to be tested as candidates in a spectrum of diseases that might involve AR dysfunction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00231616
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Insertion/deletion polymorphism in the angiotensin-converting enzyme gene associated with macroangiopathy and blood pressure in patients with non-insulin-dependent diabetes mellitus (1995)
    Springer
    Journal of molecular medicine 73 (1995), S. 307-311 
    Details
    ISSN: 1432-1440
    Keywords: Atherosclerosis ; Hypertension ; Type 2 diabetes ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In the search for new risk factors for diabetic macroangiopathy the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme gene was studied in 237 consecutive patients (125 men and 112 women) with non-insulin-dependent diabetes. The female population showed an excess of ischemic electro-cardiographic changes or definite myocardial infarctions in the patients homozygous for the deletion [D/D; odds ratio (OR) 2.8; 95% confidence interval (CI) 1.4–5.3] and in the insertion/deletion heterozygotes (I/D; OR 1.8; CI 1.1–3.1) compared with the patients homozygous for the insertion (I/I). In the total series coronary heart disease, cerebrovascular disease, and claudication were more often observed in the patients with I/D (OR 1.5; CI 1.0–2.2) or the D/D genotype patients (OR 1.7; CI 1.1–2.6) than in those with the genotype I/I. The systolic blood pressure was lower in patients with genotype I/I (138±19 mmHg) than in those with the genotype I/D (149±22 mmHg) or D/D (150±21 mmHg; P〈0.02). The prevalence of hypertension and the median urinary albumin excretion rate also tended to be lowest in the I/I genotype patients. Multiple logistic analysis revealed that in women the angiotensin-converting enzyme D/D genotype is independently associated with coronary heart disease. Our findings suggest that variation at the angiotensin-converting enzyme gene locus is one of the factors involved in the predisposition of diabetic patients to the development of arterial disease and hypertension.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00231617
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    A genetic study of idiopathic focal dystonias (1995)
    Springer
    Journal of neurology 242 (1995), S. 508-511 
    Details
    ISSN: 1432-1459
    Keywords: Dystonia ; Torticollis ; Blepharospasm ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The inheritance of focal dystonias was investigated in 43 families containing 43 index cases with torticollis (n = 21), blepharospasm (n = 18) and writer's cramp (n = 4). They generated a potential population of 235 first-degree relatives, and 168 out of 179 living first-degree relatives were examined. Ten relatives with dystonia were identified in ten families. Another two parents from two of the same group of ten families were affected according to the family history. The majority of the secondary cases (six patients, five siblings, and one child) were not aware of any dystonia. The tendency for affected relatives to have the same type of dystonia as index patients was observed only for torticollis. Overall, 23% of index patients had relatives with dystonia. Segregation analysis suggested the presence of an autosomal dominant gene or genes with reduced penetrante underlying focal dystonia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00867421
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Characterization of B-cell lines from SLE patients and their relatives (1995)
    Springer
    Rheumatology international 15 (1995), S. 89-93 
    Details
    ISSN: 1437-160X
    Keywords: SLE Lupus ; BBV transformation ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Epstein-Barr-virus (EBV)-transformed lymphoblastoid B-cell lines were generated from peripheral blood lymphocytes of 55 patients with systemic lupus erythematosus (SLE) and 44 healthy relatives. All donors have previously been extensively characterized with regard to clinical, serologic, and genetic parameters. Here, peripheral blood lymphocytes and lines were characterized for cell surface antigens. Furthermore, autoantibody production and proliferation rate of the cell lines were monitored. A significant difference between patients and relatives was the lower proliferation rate of EBV-transformed cell lines of the SLE patients. All SLE cell lines are available for interested researches and can be obtained from the European Cell Bank, Salisbury, UK.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00302123
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Industrial mycology and the new genetics (1995)
    Springer
    Journal of industrial microbiology and biotechnology 14 (1995), S. 355-364 
    Details
    ISSN: 1476-5535
    Keywords: Transformation ; Fungi ; Yeast ; Genetics ; Biotechnology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The genetic investigation of fungi has been extended substantially by DNA-mediated transformation, providing a supplement to more conventional genetic approaches based upon sexual and parasexual processes. Initial transformation studies with the yeastSaccharomyces cerevisiae provided the model for transformation systems in other fungi with regard to methodology, vector construction and selection strategies. There are, however, certain differences betweenS. cerevisiae and filamentous fungi with regard to type of genomic insertion and the availability of shuttle vectors. Single-site linked insertions are common in yeast due to the high level of homology required for recombination between vectored and genomic sequences, whereas mycelial fungi often show a high frequency of heterologous and unlinked insertions, often in the form of random and multiple-site integrations. While extrachromosomally-maintained or replicative vectors are readily available for use with yeasts, such vectors have been difficult to construct for use with filamentous fungi. The development of vectors for replicative transformation with these fungi awaits further study. It is proposed that replicative vectors may be inherently less efficient for use with mycelial fungi relative to yeasts, since the mycelium, as an extended and semicontinuous network of cells, may delimit an adequate diffusion of the vector carrying the selectable gene, thus leading to a high frequency of abortive or unstable transformants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01569951
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Genetic research, adolescents, and informed consent (1995)
    Springer
    Theoretical medicine and bioethics 16 (1995), S. 347-373 
    Details
    ISSN: 1573-1200
    Keywords: Genetics ; human research ; adolescence ; child ; informed consent ; decision making ; medical ethics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Philosophy
    Notes: Abstract The participation of adolescents in genetic research engenders unusual problems concerning the nature of their informed consent. In this study we analyze 70 consent documents collected from genetics investigators in the United States who conduct research with children and adolescents. We find that many consent documents do not reflect either the current or the developing ethical and legal standards for research with adolescents and that in many cases the documents are simply confusing or unclear. We make recommendations for change to reflect more adequately the changing perspective concerning the autonomous decision-making capacity of adolescents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00995481
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Have fishes had their chips? The dilemma of threatened fishes (1995)
    Springer
    Environmental biology of fishes 43 (1995), S. 1-27 
    Details
    ISSN: 1573-5133
    Keywords: Conservation ; Extinction ; Rarity ; Biodiversity ; Breeding guilds ; Endemism ; Speciation ; Habitat degradation ; Environmental management ; Invasive fishes ; Genetics ; Ecology ; Stenotopy ; Captive propagation ; Legislation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Synopsis The conservation status and factors threatening fishes worldwide are reviewed in order to introduce a series of one-page articles on ‘Threatened fishes of the world’, and to encourage the incorporation of information on threatened fishes into international conservation programmes. Information on fish extinction and threat rates are compared with those of other animal groups, and the unique characteristics of fish conservation problems are highlighted. At present 979 species of fishes are listed as threatened in the IUCN Red List and at least 36 species and three subspecies are listed as recently extinct. It is argued that these figures are probably gross underestimates and that they may mislead conservation authorities and resource users about the seriousness of the situation. Freshwater fishes may be the most threatened group of vertebrates after the Amphibia. Urgent action is required to save many narrowly endemic, stenotopic species from extinction, especially in Africa, Asia and South America. The conservation of common species that drive essential ecological processes is also important. Anthropogenic pressures, especially habitat degradation, the introduction of invasive species and pollution, on inland and coastal waters are particularly severe and many major fish communities are threatened with elimination throughout the world. The conservation of marine fishes is complicated by the fact that it is difficult to ascertain their rarity. The importance of the retention of genetic variation is highlighted, and both orthodox and innovative conservation measures are encouraged. Further research on minimum viable populations, genetics, and the factors that cause fishes to become vulnerable to extinction, is urgently required.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00001812
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Domestication via hybridization of the wild tetraploid oats Avena magna and A. murphyi (1995)
    Springer
    Theoretical and applied genetics 91 (1995), S. 639-646 
    Details
    ISSN: 1432-2242
    Keywords: Gene introgression ; Genetics ; Linkage ; Taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The wild tetraploid (2n=28) oat species Avena magna and A. murphyi have been domesticated by having been transferred from the common oat, A sativa (2n=42), the characteristics of non-shedding spikelets glabrous and yellow lemma, and reduced awn formation. Domestication has been achieved by crossing the common oat with either of the tetraploid species and then backcrossing the pentaploid hybrids with pollen of the tetraploid wild parent. Among the BC plants obtained only a few produced some seeds. Fertile tetraploids exhibiting the domesticated syndrome have been selected for in the F2 generation. Although morphologically they were almost indistinguishable from the common oat, they were tetraploids. Wild x domesticated A. magna hybrids were vigorous and fertile. They retained their spikelets at maturity, lemma color and pubescence were intermediate between the parental lines, and awns were formed only on the lower floret of the spikelet. Each of these characteristics segregated in a 3∶1 fashion, indicating single gene control, as in the common oat. These four characteristics formed a linkage group in one F2 family and two linkage groups in the other two families. The usefulness of the domesticated tetraploids for oat research and production has been discussed. Taxonomically, the domesticated tetraploids were ranked as subspecies: A. magna ssp. domestica, and A. murphyi ssp. rigida.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223291
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    Myotonic dystrophy in a large Sicilian kinship: a case report (1995)
    Springer
    Child's nervous system 11 (1995), S. 453-455 
    Details
    ISSN: 1433-0350
    Keywords: Myotonic ; Dystrophy ; Muscle disease ; Genetics ; Case report
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A large Sicilian kinship in which myotonic dystrophy (DM) affected spanning four generations is presented. The pedigree clearly illustrates the phenomenon of anticipation, and illustrates that this phenomenon is more marked when transmission occurs through an affected female rather than an affected male. The pedigree is interpreted in light of recent genetic advances in DM. Neurosurgeons and neurologists should consider a diagnosis of DM when asked to evaluate a floppy infant with enlarged lateral ventricles, and should be aware of special features regarding its inheritance pattern.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00334964
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Masthead (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Tripodal Triamidostannates as Building Blocks in the Generation of Sn - M-Bonded Heterobimetallics (M = Fe, Ru) (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 29-34 
    Details
    ISSN: 0009-2940
    Keywords: Tripodal ligands ; Triamidostannates ; Metal-metal bonds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: By in situ lithiation of the trifunctional amines H3CC(CH2NHSiMe3)3, PhC(CH2NHSiMe3)3, and HC{SiMe2NH(p-Tolyl)}3 and subsequent reaction with SnCl2 the corresponding triamidostannates were obtained. These were coupled with CpM(CO)2Cl (M = Fe, Ru) to yield the M - Sn-bonded heterobimetallics 9-14 of which H3CC(CH2NSiMe3)3SnFe(CO)2Cp (9) was characterized by a single-crystal X-ray structure analysis. Of the in situ-generated amidostannates only [HC{SiMe2N(p-Tolyl)}3Sn][Li(THF)3] (8) could be isolated as a uniform product and characterized analytically and spectroscopically.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280105
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    The Structures of [X2Y—N—YX2]+ Cations (X = F, Cl; Y = S, Se). A Comparison of X-ray and ab Initio Studies[1] (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 35-40 
    Details
    ISSN: 0009-2940
    Keywords: Selenium-nitrogen compounds ; Sulfur-nitrogen compounds ; Calculations, ab initio ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structures of cationic species of the series [X2Y—N—YX2]+ (X = F, Cl; Y = S, Se) have been computed ab initio using all electron treatments for first-row elements and sulfur and quasi-relativistic pseudopotentials for Se and Cl. Splitvalence basis sets with polarization and diffuse functions were employed. The MP2 results for the (non-isostructural!) cations [Cl2Se—N—SeCl2]+ (1: Cs) and [F2S—N—SF2]+ (2: C2v) are in excellent agreement with the experimental (X-ray) observations. Both structures represent local minima. A deeper minimum for either of the cations is represented by another C2v isomer which for crystal lattice energy reasons is stable in the isolated state only. The geometries of the hitherto unknown species [Cl2S—N—SCl2]+ (3) and [F2Se—N—SeF2]+ (4) have been assessed by ab initio HF calculations. In analogy to 2, cations 3 and 4 are predicted to prefer C2v symmetry. Therefore, 1 exhibits unusual structural features. According to strictly localized natural bond orbital analysis (NBO), the central nitrogen atoms in 1 and 2 possess two lone pairs of electrons (LP: one sp hybrid and one p orbital). The relatively short Se—N and S—N bond distances in 1 (1.741-1.760 Å) and 2 (1.551 Å) can best be attributed to LP(N)→s̰*(Y—X) negative hyperconjugation (1: Y = Se, X = Cl; 2: Y = S, X = F).
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Die fördernde Rolle von Phosphinoester-Liganden bei der Synthese neutraler Carben-, Vinyliden- und Allenyliden-Ruthenium(II)-KomplexeHerrn Professor Hubert Schmidbaur zum 60. Geburtstag gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 49-62 
    Details
    ISSN: 0009-2940
    Keywords: Ruthenium(II) complexes, octahedral ; Phosphino esters as mono- and bidentate ligands ; Fluxional behaviour ; Carbene complexes ; Vinylidene complexes ; Allenylidene complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinylidene Transition-Metal Complexes, XXXV[1].  -  The Supporting Role of Phosphino Ester Ligands for the Synthesis of Neutral Carbene, Vinylidene and Allenylidene Ruthenium(II) ComplexesThe reaction of [RuCl2(PPh3)3] (1) with the phosphino esters iPr2P(CH2)nCO2R (2-4) leads to complete (n = 1; R = CH3, C2H5) or partial (n = 2; R =CH3) displacement of the PPh3 ligands and formation of the octahedral ruthenium(II) complexes [RuCl2{k2(P,O)-iPr2PCH2CO2R}2] (5, 6) and [RuCl2(PPh3){k(P)-iPr2PCH2CH2CO2Me}{k2(P,O)-iPr2PCH2CH2CO2Me}] (7). Treatment of 5 with LiBr and LiI affords the dibromo- and diiodoruthenium derivatives 8 and 9. While compound 5 reacts with CO and SO2 by cleavage of one Ru - O bond to yield the 1:1 adducts [RuCl2(L){k(P)-iPr2PCH2CO2Me}{k2(P,O)-iPr2PCH2CO2Me}] (10, 11), the reaction of the dibromo derivative 8 with CO in solution gives the dicarbonyl complex [RuBr2(CO)2{k(P)-iPr2PCH2CO2Me}2](13). If CO is passed over 8 in the solid state, the corresponding monocarbonyl compound 14 is formed. The hydridoruthenium(II) complex 16, which is obtained from equimolar amounts of [RuHCl(CO)(PiPr3)2] (15) and 2, reacts with HC≡CMe by insertion to give the vinyl derivative [RuCl{E - CH=CHMe}(CO)(PiPr3){k2(P,O)-iPr2CH2CO2Me}] (17). Treatment of 5 with HC̊' (R' = H, Me, tBu, Ph) and of 6, 8, 9 with HC≡CPh affords upon photochemical activation the octahedral vinylidene complexes [RuX2-(=C=CHR){k(P)-iPr2PCH2CO2R}{k2(P,O)-iPr2PCH2CO2R}] (18-21 and 23-25) in good to excellent yield. At room temperature, these compounds (with the exception of 25) are highly fluxional in solution. From 31P-NMR measurements, the free energies of activation ΔG
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Reaktionen von R2Al—AlR2 (R = CH(SiMe3)2) mit Trimethylsilylazid  -  Insertion in die Al—Al-Bindung und Abbau zum trimeren Dialkylaluminiumazid (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 81-85 
    Details
    ISSN: 0009-2940
    Keywords: Aluminium-aluminium bond ; Insertion of trimethylsilyl azide ; Trimeric dialkylaluminium azide ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of R2Al—AlR2 (R = CH(SiMe3)2) with Trimethylsilyl Azide  -  Insertion into the Al—Al Bond and Formation of a Trimeric Dialkylaluminium AzideTetrakis[bis(trimethylsilyl)methyl]dialuminium(4) (1) reacts with trimethylsilyl azide under insertion of one nitrogen atom into the Al—Al bond. As shown by NMR spectra and crystal structure the product contains three and four coordinated Al atoms due to the coordination of the α-nitrogen atom of the azide group to one of the Al atoms. An electronically delocalized N3-system is formed with a N—N bond length of 132.0 pm and a bond order of 1.5 for both N—N bonds. With an excess of trimethylsilyl azide further reaction is observed only under mild irradiation conditions with an exchange of the azide group between Si and Al and formation of Me6Si2 and the dialkylaluminium azide 3, which is better synthesized by the reaction of Me3Si—N3 with Cl—Al[CH(SiMe3)2]2. The sterically highly shielded aluminium azide 3 is a trimer in the solid state showing a non-planar 12-membered Al3N9 heterocycle with short N—N bonds (114 pm).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280112
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Selective Activation of Aromatic C - H Bonds with Lithium Atoms at 77 K (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 91-92 
    Details
    ISSN: 0009-2940
    Keywords: C - H bond activation ; Lithum atoms ; Cocondensation ; Aryllithium ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the presence of donor bases like THF lithium atoms are able to activate benzene derivatives under cryogenic reaction conditions. Only ring-metalated products and solid lithium hydride are formed selectively. The thermodynamically favored product benzyllithium or biphenyl generated by dimerization of free phenyl radicals are not found. This is one of the very few examples of metal atoms undergoing a C - H activation without further photoexcitation.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280114
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Protolysis of Tri-tert-butylazadiboriridine: Formation of a B-H-B Bridge in Unusual Coordination (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 99-103 
    Details
    ISSN: 0009-2940
    Keywords: Tri-tert-butylazadiboriridine ; (Hydroboryl)(methoxyboryl)amine ; 2,3-μ-Hydro-1,2,3-azoniadiborata-l-cyclopropenes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The B—B bond of tri-tert-butylazadiboriridine [—NR—BR—BR—] (R = tBu; 1) is oxidized by MeOH to give the (hydroboryl)(methoxyboryl)amine H—BR=NR-BR(OMe) (2a). μ-2,3-Hydroazoniadiborata-1-cyclopropenes [=NR—BR(X)—μH—BR=] (3a, 3c-e) are formed by the action of the acids HX upon 1. A similar hydrogen bridge as in 3a-e is formed during the hydroboration of 1 by catecholborane, yielding 3f. A B atom is identified in the products 3a-f to be planarly coordinated by four atoms, two of which are forming a BHB three-center bond with that B atom. This is a novel bonding situation in boron chemistry. The structures of the products are deduced from 1H-, 11B-, and 13C-NMR spectra and are confirmed by X-ray structural analyses of 2a, 3a, and 3c.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Synthese und Struktur zweikerniger Kupfer(II)-Komplexe eines neuen Hexaaza-Makrocyclus mit verbrückenden Oxalat- und Acetat-Ionen (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 115-119 
    Details
    ISSN: 0009-2940
    Keywords: Polyazamacrocycles ; Dinucleating ligands ; Copper complexes ; Oxalate complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Structure of Dinuclear Copper(II) Complexes of a Novel Hexaaza Macrocycle Containing Bridging Oxalate and Acetate IonsNon-template Schiff base [2 + 2] condensation of pyridine-2,6-dicarbaldehyde with 1,4-diamino-2-butyne yields the hexaazamacrocyclic ligand 1, which is converted to 2 by NaBH4 reduction of the imino groups. Two dinuclear copper(II) complexes of 2 containing oxalate and acetate ions, [(2)Cu2(μ-C2O4)](BPh4)2 (3) and [(2)Cu2(μ-CH3CO2)(OH2)](PF6)2.25-(NO3)0.75 (4), were characterized by X-ray crystallography. The oxalate ligand in 3 forms a (μ-η4:η4) bridge between the copper atoms. Compound 4 contains a syn-anti-bridging acetate ion. The Cu-Cu distances are 5.315 Å in 3 and 4.746 Å in 4, respectively. Oxalate can be separated from other carboxylates in aqueous solution by selective binding to the [(2)Cu2] unit and precipitation of 3.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Synthesis, X-Ray Crystal Structure and Magnetic Characterization of the First “Ni3S4N3” Nickel Thiolate Cluster (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 125-129 
    Details
    ISSN: 0009-2940
    Keywords: Nickel cluster ; Nickel thiolate ; Hydrogenase ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The tridentate N,O,S-ligand (RS)-2-[(2-mercapto-1-methylamino)ethyl]phenol (rac-1) was prepared from ortho-hydroxy-chloroacetophenone in three steps. When this ligand was treated with nickel(II) acetate, the novel “Ni3S4N3” cluster rac-3 was obtained. The X-ray crystal structure of rac-3 unambiguously revealed the pseudo-C3 symmetric structure of this novel nickel cluster, which is made up by three nickel ions, one sulfide sulfur atom, and three homochiral ligand molecules, each contributing one thiolate sulfur atom and one amine nitrogen atom to the ligation of the metal ions. According to NMR-spectroscopic results, this highly symmetric structure is maintained in solution. The magnetic studies revealed diamagnetic behavior in the solid state, although antiferromagnetic interaction of the metal centers cannot absolutely be excluded.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280207
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Stereospecific Ligand Substitutions in Manganese(I) Complexes (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 151-155 
    Details
    ISSN: 0009-2940
    Keywords: Tripodal ligands ; Phosphane ligands ; Thioethers ; Manganese complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Treatment of fac-[(P2SPh-P,P')Mn(CO)3Br] and fac-[(PS2Ph-P,S)Mn(CO)3Br] [P2SPh: Z = PPh2; PS2Ph: Z = SPh in CH3C-(CH2PPh2)(CH2SPh)(CH2Z)] with silver hexafluorophosphate yields the η3-tripodal manganese complexes [(P2SPh-P,P',S)Mn(CO)3]PF6 (7) and [(PS2Ph-P,S,S')Mn(CO)3]PF6 (9), respectively, whereas the reaction of CH3C(CH2PPh2)2-(CH2SH) with Mn(CO)5Br gives directly [CH3C(Ph2-PCH2)2(CH2S)-P,P',S]Mn(CO)3 (11). Both ionic complexes 7 and 9 undergo stereospecifically ligand substitution upon treatment with Br-, I-, N-3, SCN- and CN- to give syn-fac-[(P2SPh-P,P')Mn(CO)3X] and syn-fac-[(PS2Ph-P,S)Mn(CO)3X] (X = Br, I, SCN, N3, CN) respectively, but the neutral complex 11 fails to undergo such a substitution reaction with these ions. However, reaction of I- with the complex [(PSMe)-P,P',S]Mn(CO)3]BF4 (20) [P2SMe = CH3C(CH2-PPh2)2(CH2SCH3)), which is obtained from the S-alkylation of 11 with (CH3)3OBF4, affords syn-fac-[(P2SMe)-P,P']Mn(CO)3I (22s) exclusively. The possible reaction mechanism of this ligand substitution is discussed.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280211
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Oxacycloalkenyliden-Komplexe von Chrom, Molybdän und Wolfram: Synthese, Anellierung mit Alkinen und Diels-Alder-Reaktionen mit Dienen (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 157-161 
    Details
    ISSN: 0009-2940
    Keywords: Carbene ligands ; Chromium complexes ; Molybdenum complexes ; Tungsten complexes ; Annulation reaction ; Diels-Alder reaction ; Oxacyclopentenylidene ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of Complex Ligands, LXI[1]. - Oxacycloalkenylidene Complexes of Chromium, Molybdenum, and Tungsten: Synthesis, Their Annulation with Alkynes and Diels-Alder Reaction with DienesLithiiated propargylic ether 1 reacts with M(CO)6 (M = Cr, Mo, W) to give the 2-oxacyclic carbene complexes 2-4 containing an α,β-double bond and a cyclic acetal structure which serves as a protected benzoyl group. Reaction of the chromium complex 2 with tolan leads to an acyl hydroquinone derivative 5. The tungsten complex 3 undergoes a [4 + 2] cycloaddition with cyclopentadiene to give two diastereomeric oxatricyclic carbene complexes 6 and 7 with an endo/exo selectivity of 3:1. The stereochemistry of the Diels-Alder reaction is controlled by the configuration of the acetal carbon center.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280212
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Darstellung und Komplexierung von 1,4-Dimethyl-2,3-bis(isopropyliden)-1,4-diboratetralinHerrn Professor Nils Wiberg zum 60. Geburtstag gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 183-185 
    Details
    ISSN: 0009-2940
    Keywords: 1,4-Diboranaphthalines ; 2,7-Diboradodeca-1,3,9,11-tetraenes ; Cobalt complexes ; Rhodium complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Complexation of 1,4-Dimethyl-2,3-bis(isopropylidene)-1,4-diboratetraline1,4-Dimethyl-2,3-bis(isopropylidene)-1,4-diboratetraline (2) is obtained from o-dilithiumbenzene and 2,5-dimethyl-3,4-bis(chloromethylboryl)-2,4-hexadiene in 61% yield. Its complexation with cyclopentadienylbis(ethene)cobalt leads to the triple-decker bis(η5-cyclopentadienylcobalt)-μ-η6,η6-1,4-dimethyl-2-isopropenyl-3-isopropyl-1,4-dihydro-1,4-dibora-naphthaline (3) in low yield. However, the reaction of 2 with (C5H5)Rh(C2H4)2 and (C5Me5)Co(C2H4)2 originates complexes of a tricyclic ligand formed from 2 via conrotatoric [2 + 2] cycloaddition of the isopropylidene groups. (η5-Cyclo-pentadienylrhodium)-η6-tricyclo-[6.4.0.03,6]-2,4,4,5,5,7-hexamethyl-2,7-diboradodeca-1,3,9,11-tetraene (4), (η5-pentamethylcyclopentadienylcobalt)-η6-tricyclo-[6.4.0.03,6]-2,4,4,5,5,7-hexamethyl-2,7-diboradodeca-1,3,9,11-tetraene (5) and its related dinuclear complex 6 could be isolated in 29, 10, and 31%, respectively. Their constitutions are derived from spectroscopic data and proven by X-ray structure analysis of 4.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280216
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Zerfall von Nitrosylazid, N4O: Existieren auch cyclische Stickstoff-Oxide? (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 201-203 
    Details
    ISSN: 0009-2940
    Keywords: Nitrogen oxides ; Calculations, ab initio ; Tetranitrogen monoxide ; Dinitrogen monoxide ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Decomposition of Nitrosyl Azide, N4O: Are Cyclic Nitrogen Oxides Existent?The unimolecular decomposition of nitrosyl azide (tetranitrogen monoxide), N4O, was studied at the electron-correlated, spin-restricted RMP2 level with the 6-31G(d,p) and 6-31+G* basis sets. Frequency calculations were performed at 6-31+G* on the optimized structures. It is demonstrated that the experimentally established trans-trans-N4O (Cs) may either interconvert into cis-cis-N4O which upon decomposition forms cyclic N4O (C2v) as an intermediate species to finally give N2O (C∞v) and N2, or trans-trans-N4O may directly dissociate into cyclic N2O (C2v) and N2. All structures determined were rationalized by energy hypersurface calculations.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280220
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Synthesis and Characterization of Mononuclear Titanium Complexes Containing a Bis(phenoxy) Ligand Derived from 2,2′-Methylene-bis(6-tert-butyl-4-methylphenol) (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 221-227 
    Details
    ISSN: 0009-2940
    Keywords: Titanium complexes ; Bidentate phenoxy ligands ; Bulky phenols ; Lewis acidity ; Pentacoordination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new titanium complexes of the general type Ti(mbmp)X2 (X = Br, I; OMe, OiPr, OtBu), containing a bidentate bis(phenoxy) ligand derived from 2,2′-methylenebis(6-tert-butyl-4-methylphenol) (mbmpH2), was prepared. The 1H-chemical shifts for the protons of the methylene link were found to vary considerably as a function of the ligand X. Reaction of Ti(OiPr)4 with two equivalents of mbmpH2 gave the C2-symmetric spiro-titanate complex Ti(mbmp)2. The crystalline labile solvent adducts of the dichloro complex Ti(mbmp)Cl2 with THF and DME were isolated and characterized. A single-crystal X-ray structural analysis revealed the THF adduct to be a mono(THF) adduct with a trigonal-bipyramidal configuration, the bidentate mbmp ligand spanning an apical and equatorial site and the THF ligand occupying the remaining apical position.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280304
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Darstellung und Charakterisierung der Tetrahedrane [CpM(CO)2]3P (M = Mo, W) sowie der Derivate [CpMo(CO)2]3P-Mo(CO)5 und [CpW(CO)2]3P-W(CO)5 (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 197-199 
    Details
    ISSN: 0009-2940
    Keywords: μ3-Phosphorus-trimolybdenum tetrahedrane ; μ3-Phosphorus-tritungsten tetrahedrane ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Characterization of the Tetrahedranes [CpM(CO)2]3P (M = Mo, W) and Their Derivatives [CpMo(CO)2]3P-Mo(CO)5 and [CpW(CO)2]3P-W(CO)5The reaction of Na[CpM(CO)3] (M = Mo, W) with PCl3 in diglyme yields the cluster compounds [CpMo(CO)2]3P-Mo(CO)5 (2a) and [CpW(CO)2]3P-W(CO)5 (2b) in good yields as well as the tetrahedranes [CpMo(CO)2]3P (3a) and [CpW(CO)2]3P (3b) as side products. Compounds 3a, b are obtained independently by the reaction of 2a, b with PPh3. The clusters 2a, b and 3a, b were characterized spectroscopically (IR, NMR, MS), and X-ray structure determinations were carried out on 2a, b.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280219
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Photocatalytic Oxygenation of Selected Cycloalkenes in Aqueous Solutions Induced by Water-Soluble Metal Porphyrin Complexes (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 229-234 
    Details
    ISSN: 0009-2940
    Keywords: Photooxygenation ; Dioxygen activation ; Metalloporphyrins ; Epoxidation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Water-soluble manganese(III) as well as iron(III) porphyrinates are introduced as light-sensitive precursor compounds for the photocatalytic activation of dioxygen in aqueous solutions. It is shown that in the presence of α-pinene (4) and the further cycloalkenes 11-13 photocatalytic oxygenation reactions occur. The dependence of the selectivity of the oxygen transfer to the olefin on both the presence of water and the variation of the substrate-to-catalyst ratio is discussed. The catalyst may be conveniently separated from the substrates/products by using aqueous solvent systems.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Carbohydratocarbene Complexes of Manganese and RheniumDedicated to Prof. Hans H. Brintzinger on the occasion of his 60th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 373-378 
    Details
    ISSN: 0009-2940
    Keywords: Carbene complexes ; Carbyne complexes ; Carbohydrates ; Diastereoselective addition ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cationic carbyne complexes [Cp(CO)2M≡CR]+ [BX4]- [M = Mn, X = F: R = Ph (1), Tol (2); M = Re, X = 3,5-C6H2(CF3)2: R = Ph (3)] add the anion of monodeprotonated protected mannofuranose (4a), glucofuranose (4b), and fructopyranose (4c) to the carbyne carbon atom to form the carbohydratocarbene complexes 5a-c, 6a, b, and 7a. With 5b, 5c, and 6b the addition proceeds with retention of configuration at the anomeric center. Due to inversion of configuration in the deprotonation step the complexes 5a, 6a, and 7a are obtained as β-glycosides. The carbene ligand is oxidatively cleaved from the metal by trimethylamine N-oxide or air. Cleavage of the C(carbene)—O bond with reformation of the cation of the carbyne complex 2 is achieved by reaction of 6a with BCl3. Photolysis of [Cp(CO)2Mn=C(Ph)OEt] in the presence of L affords the carbene complexes [Cp(CO)(L)Mn=C(Ph)OEt] [L = P(OMe)3 (11), P(Tol)3 (12)]. Ethoxide abstraction from 11 and 12 by BF3 gives the chiral cationic carbyne complexes [Cp(CO)(L)Mn=CPh]+[EF4]- (13, 14) which add 4a to form the corresponding mannofura-nosylcarbene complexes (15, 16). When 0.5 equivalents of 4a are employed in the reaction with 13, 14 the ratio of diastereomers is 3:2, both for 15 and 16. Complex 11 was characterized by an X-ray structural analysis.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280409
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Metallorganische Verbindungen der Lanthanoide, 89. Cyclooctatetraenyl-Komplexe der frühen Übergangsmetalle und Lanthanoide, 6. (Cyclooctatetraenyl)[N,N′-bis(trimethylsilyl)benzamidinato]-und -[diphenylbis(trimethylsilylimido)phosphinato]-Komplexe der Seltenen Erden; Röntgenstrukturanalyse von (C8H8)Tm[PhC(NSiMe3)2](THF), (C8H8)Lu[4-MeOC6H4C(NSiMe3)2](THF) und (C8H8)Nd[Ph2P(NSiMe3)2](THF) (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 395-404 
    Details
    ISSN: 0009-2940
    Keywords: Lanthanides, organo-, complexes ; Cyclooctatetraenyl complexes ; Benzamidinate ligands ; Diimidophosphinate ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organometallic Compounds of the Lanthanoids, 89. - Cyclooctatetraenyl Complexes of the Early Transition Metals and Lanthanoids, 6. - (Cyclooctatetraenyl)[N,N′-bis(trimethylsilyl)benzamidinato]- and -[diphenylbis(trimethylsilylimido)-phosphinato] Complexes of the Rare Earths; X-Ray Structural Analyses of (C8H8)Tm[PhC(NSiMe3)2](THF), (C8H8)Lu[4-MeOC6H4C(NSiMe3)2](THF), and (C8H8)Nd[Ph2P(NSiMe3)2](THF)[(C8H8)Ln(μ-Cl)(THF)2]2 or [(C8H8)Ln(μ-O3SCF3)(THF)2]2 (Ln = Y, Ce, Pr, Nd, Sm, Tm, Lu) react with Na[4-RC6H4C(NSiMe3)2] (R = H, OMe, CF3) or Li[PhC(NSiMe3)2] to give the monomeric (cyclooctatetraenyl)lanthanide benzamidinates (C8H8)Ln[4-RC6H4C(NSiMe3)2](THF) [R = H, Ln = Y (1), Ce (4), Pr (6), Nd (8), Sm (10), Tm (12), Lu (15); R = OMe, Ln = Y (2), Ce (5), Pr (7), Nd (9), Sm (11), Tm (13), Lu (16); R = CF3, Ln = Y (3), Tm (14), Lu (17)]. The reaction of [(C8H8)Ln(μ-Cl)(THF)2]2 (Ln = Ce, Pr, Nd, Sm) with Li[Ph2P(NSiMe3)2] in THF leads directly to the monomeric compounds (C8H8)Ln[Ph2P(NSiMe3)2](THF) [Ln = Ce (18), Pr (19), Nd (20), Sm (21)] in good yields. The 1H-, 13C-, 31P- and 29Si-NMR and mass spectra of the new compounds as well as the molecular structures of 12, 16, and 20 are discussed. The Raman spectra of the complexes 1-3, 12, and 14-17 have been studied in detail.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280411
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Perfluororganochalkogensäuren in hohen Oxidationsstufen (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 423-428 
    Details
    ISSN: 0009-2940
    Keywords: Perfluoroethylselenoic acid, -salts, -esters ; Bis(pentafluorophenyl)tellurium(IV) acid, mixed anhydrides, -tellurium(VI) oxide, -tetrakis(trifluoromethylsulfonate), -dihydroxybis(trifluoromethylsulfonate) ; Pentafluorophenyltellurium(IV) oxoacid ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Perfluoroorganochalcogenic Acids in Higher Oxidation StatesPentafluoroethylseleninic acid is oxidized by KMnO4 in slightly alkaline aqueous solution to give K[C2F5SeO3]. With HClO4 the salt is converted into the free acid. Neutralisation of C2F5SeO3H with NaOH, Ag2O, NH3 + H2O provides the corresponding salts. The ethyl ester is made from Ag[C2F5SeO3] and C2H5I. Oxidation of C6F5TeC6F5 with concd. HNO3 yields C6F5Te(OH)ONO2 which on controlled hydrolyses gives (C6F5)2Te(OH)2. Strong acids like HClO4 or H2SO4 form mixed anhydrides like (C6F5)2Te(OH)ClO4 or (C6F5)2Te(OH)OS(O)2OTe(OH)(C6F5)2. For the latter compound a cyclic or noncyclic polycondensate form cannot be ruled out. Acidic 35% H2O2 solution oxidizes (C6F5)2Te(OH)2 at 40°C (48 h) to give (C6F5)2TeO2. This anhydride dissolves only in CF3SO3H forming (C6F5)2Te(OSO2CF3)4. It is soluble in CH3CN and reacts in solution with water to yield (C6F5)2Te(OH)2(OSO2CF3)2. Oxidation of C6F5TeTeC6F5 with concd. HNO3 provides oligomeric [C6F5Te(O)OH]x which still contains some HNO3. A single-crystal X-ray structure determination carried out on [(C6H5)4As][C2F5SeO3] shows convincingly that the central selenium atom is coordinated by three equivalent oxygen atoms with d(Se-O) = 1.614(3) Å, proving that Se has the oxidation state VI.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280415
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Molecular Modeling, a Tool for Predicting Structural Effects on the Macrocyclization Reaction between Bis(vinyl or allyl) Dialdehydes and Thiophosphonic Bis(hydrazides) (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 443-447 
    Details
    ISSN: 0009-2940
    Keywords: Phosphorus macrocycles ; Molecular modeling ; Cyclocondensation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of new phosphorus dialdehydes PhP(O)-[(CH2)nCH=CHC6H4CHO]2 (4a-c, 5a) (n = 0:4, n = 1:5; a:para, b:meta, c:ortho), with thiophosphonic bis(hydrazide) PhP(S)[NMeNH2]2 (6) yields macrocyclic compounds 9b′, c′, 10a′, 9a″, b″, c″, 10a″ and 9c′″, arising from the cyclocondensation of one, two, or three equivalents of each reagent, respectively. Molecular modeling of 4a-c, 5a, 6 and of the intermediate monocondensation products 7a-c, 8a was carried out and points out the importance of the geometry of the starting reagents in the competition between inter- and intramolecular cyclocodensation.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280502
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Synthesis, Structures and Properties of CF3S-Substituted Tellurium Compounds (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 477-480 
    Details
    ISSN: 0009-2940
    Keywords: Tellurium, bis(sulfinylamido)-, bis(trifluoromethylthio)- ; Thiachalcogenadiazole ; Ditelluradiazetidine ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New preparations for the following compounds are described: Te(SCF3)2, Te(NSO)2, and Cl2Te(NSO)2. The catalytic or thermal SO2 elimination from Cl2Te(NSO)2 affords a coordinated or non-coordinated thiachalcogenadiazole. Conversions of these compounds are reported. Evidence for the proposed mechanism for the reaction between Te(NSO)2 and SbCl5 is provided. Cl4Te2N2(SCF3)2, prepared from TeCl4 and CF3SN(SiMe3)2, reacts with LiN(SiMe3)2 to form [(Me3Si)2N]4Te2N2(SCF3)2. An X-ray structural analysis of Cl4Te2N2(SCF3)2 is presented.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280507
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Syntheses and Structures of Intramolecularly Stabilized Organoaluminium CompoundsDedicated to Professor Peter Paetzold on the occasion of his 60th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 493-497 
    Details
    ISSN: 0009-2940
    Keywords: Organoaluminium compounds ; Alanes, 2-[(dimethylamino)methyl]phenyl- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of LiAr (Ar = 2-[(dimethylamino)methyl]phenyl) with AlCl3, MeAlCl2, and Me2AlCl in a 1:1 ratio yields the corresponding organoaluminium compounds ArAlCl2, ArAl(Cl)Me, and ArAlMe2 (1-3). The alanes Ar2AlCl and Ar2AlMe (4 and 5) were synthesized from AlCl3 and MeAlCl2 with two equivalents of LiAr. The products ArAl(Cl)R [R = tBu, C(SiMe3)3] 6 and 7 are formed by the reaction of LiR with 1. The Lewis acid 1 adds the bases iPrNH2 and THF to yield the adducts 1 · iPrNH2 and 1 · THF. The structures of the products were deduced from the 1H-, 13C-, and 27Al-NMR spectra and were confirmed by X-ray structural determinations of 5 and 1 · iPrNH2.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280510
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Metallkomplexe unsymmetrisch überbrückter [N4]-Makrocyclen: Synthese, Struktur und Redoxverhalten (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 503-514 
    Details
    ISSN: 0009-2940
    Keywords: Cu, Ni, Co, Fe complexes ; Template synthesis ; Tetraaza macrocycles ; X-ray structure, H bridges, ID-coordination polymers ; Electrochemistry ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metal Complexes of Unsymmetrically Bridged [N4] Macrocycles: Synthesis, Structure and Redox BehaviourMetal complexes M-5a (M = Cu, Ni, Co, Fe, and I-Fe11) of 6,13-Di(ethoxycarbonyl)-7,12-dimethyl-benzo[b]-1,4,8,11-tetraaza-cyclotetradeca-2,5,7,11,13-pentaene and the free ligand H2-5a have been synthesized. The crystals of Cu-5a · H2O and Ni-5a · H2O consist of planar complex molecules which are linked by H bridges between the water molecules and the peripheric ester groups to give 1D chains. The average M-N distances are equal for both complexes (Cu 1.928, Ni 1.924 Å), being unexpectedly large for the nickel complex. The redox properties of all the new compounds as well as some acetyl derivatives M-5b have been examined by cyclic voltammetry and compared with those of the previously reported symmetrically phenylene (M-4) and ethylene (M-6) bridged derivatives. All complexes give a reversible single electron reduction which clearly shows the increasing electron density around the central atom in the order M-4 〈 M-5 〈 M-6. Like the carbonyl substituted tetraazaannulenes M-4 the copper complexes Cu-5 give two, the cobalt complexes Co-5 three, and the iron complex Fe-5a probably four reversible single electron oxidations. They can be attributed to the species [MIIIL-II]+, [MIILo]2+, [MIIILo]3+, and [FeIVLo]4+ with Lo being a “non innocent” neutral 1,2-quinodiimine ligand. Very surprisingly, since in contrast to Ni-4 and Ni-6, the nickel complexes Ni-5 gave no reversible oxidation.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280512
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Zinc Complexes of Histidine-Containing Di- and Tripeptides (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 541-550 
    Details
    ISSN: 0009-2940
    Keywords: Histidine peptides ; Zinc complexes ; Composition ; Solid-state structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Nine dipeptides and one tripeptide containing histidine were converted into analytically pure zinc complexes. Four different compositions were observed. The peptides used as or converted into the monoacids LH (HisGly, GlyHis, HisPhe, HisHis) form the compounds ZnL2 (11a, 12-14) and alternatively (HisGly, HisGlyGly) the compounds ZnL(BF4) (11b, 20). The peptides used as amides (HisGlyNH2, HisMetNH2) act as neutral ligands in the compounds ZnL2(ClO4)2 (15, 16). The three remaining peptides (HisAsp, AlaHis, β-AlaHis) behave like diprotonic acids LH2 forming the compounds ZnL (17-19). Spectra and solubilities indicate that complexes 11a, 13, 15, and 16 are mononuclear containing two chelating peptides bound by their amino and imidazole nitrogen atoms. All other complexes seem to be coordination polymers in some of which the amide N and O atoms are involved in the coordination. This was proven by a structure determination for Zn(GlyHis)2 (12) in which the zinc ions are coordinated octahedrally by two histidine N, two amino N, and two amide O atoms of four peptide residues.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280603
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    1,4,2-Diazaphospholothiazoles and -pyridines by a Hantzsch-Type Condensation Using Chloromethyldichlorophosphane (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 581-587 
    Details
    ISSN: 0009-2940
    Keywords: Anellated azaphospholes ; Hantzsch-type [3 + 2] cyclocondensation ; Chloromethyldichlorophosphane ; Regioselectivity ; 31P-, 1H-, 13C-NMR spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The [3 + 2] cyclocondensation of 2-amino-1,3-thiazoline, 2-aminopyridines, 2- and 4-aminopyrimidines, 2-aminopyrazine, and 2-aminoquinoline with chloromethyldichlorophosphane in the presence of triethylamine yields regiospecifically 5,6-dihydrothiazolo[2,3-e][1,4,2]diazaphosphole (3), 1,4,2-diazaphospholo[4,5-α]pyridines (12), 1,4,2-diazaphospholo[4,5-α]pyrimidines (15), 1,4,2-diazaphospholo[4,5-e]pyrimidine (17), 1,4,2-diazaphospholo[4,5-α]pyrazine (19), and [1,4,2]diazaphospholo[4,5-α]quinoline (22), respectively. Using 2-amino-1,3-thiazole (4) and 2-aminobenzothiazoles 8, we obtained mixtures of the 1,5- and 4,5-anellated 1,4,2-diazaphospholes 5/6, 9a/10a and 9b/10b, while in the case of the methyl derivative 8c only the [1,4,2]diazaphospholo[5,4-b][1,3]benzothiazole 10c was formed. In the reaction of 2-aminothiazole and 2-aminopyrazine with Chloromethyldichlorophosphane the bis(diazaphospholo)-substituted chloromethylphosphanes 7 and 20 could be detected. The new anellated 1,4,2-diazaphospholes are colorless to pale yellow crystalline moisture-sensitive solids.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280610
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Reactions at Silicon-Silicon Bonds, V. Selective Trichlorosilylation of Alkyl(diorganylamino)chlorophosphanes with Hexachlorodisilane or with Trichlorosilane/Triethylamine. - Two Routes to New Functional Trichlorosilylphosphanes (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 615-619 
    Details
    ISSN: 0009-2940
    Keywords: Reductive silylation ; Aminochlorophosphanes ; Silylphosphanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of alkyl(diorganylamino)chlorophosphanes R(R2′N)PCl 1 (1a: R = tBu, R′ = Et, 1b: R = iPr, R′ = iPr; 1c: R = iPr, R′ = Ph) with hexachlorodisilane, afforded alkyl(diorganylamino)trichlorosilylphosphanes R(R2′N)PSiCl3 2 (2a: R = tBu, R′ = Et; 2b: R = iPr, R′ = iPr; 2c: R = iPr, R′ = Ph) and silicon tetrachloride. An intermediate formed in the reaction of 1b with hexachlorodisilane, the adduct iPr(iPr2N)(Cl)P-Si(Cl)3-SiCl3 (3b = 1b · Si2Cl6), was detected by 31P- and 29Si-NMR spectra that indicate pentacoordinated silicon bound to tetracoordinated phosphorus and tetracoordinated silicon. Trichlorosilylphosphanes 2 are also available from 1 under very mild conditions by reductive trichlorosilylation with trichlorosilane in the presence of triethylamine. Compounds 2 were identified analytically, by mass spectroscopy, multinuclear NMR, and an X-ray structure determination of 2c.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280614
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Reactions of Complex Ligands, LXIVPart LXIII: Ref.. Synthesis of 5,5′-Diphenyl-2,2′-bifuran, a Biaryl Compound with Remarkable Fluorescence Properties (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 641-643 
    Details
    ISSN: 0009-2940
    Keywords: Carbene ligands ; Tungsten complexes ; 2,2′-Bifuran ; Copper coupling reaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 2-oxacyclic α,β-unsaturated carbene complex 1 reacts with an excess of dimethylamine to give the diphenylbifuran 2. The structure of 2 was established by independent synthesis from 2-phenylfuran (4) via regioselective lithiation and transmetalation to zinc and tin organometallics 6a-c and final oxidative copper coupling reactions.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280618
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Ligandgesteuerte P2-Verknüpfung zu einem acyclischen P4-LigandenHerrn Prof. Peter Puetzold zum 60. Geburtstag gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 635-639 
    Details
    ISSN: 0009-2940
    Keywords: P2 and P4 ligands ; Ligand-induced P2 coupling ; Cobalt complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ligand-Induced P2 Coupling to an Acyclic P4 LigandThe further terminal coordination of M(CO)5 (M = Cr, Mo W) to [(Cp‴Co)2(μ-η2:2-P2)2] (1), Cp‴ = 1,2,4-tBu3C5H2, affords the polynuclear cobalt complexes [(Cp‴Co)2(μ3(4)-η4:4:1:(1)-P4){M(CO)5}n], n = 1; M = Cr (2a), Mo (2b), W (2c) and n = 2, M = W (3). The X-ray crystal structure analyses as well as low-temperature 31P-NMR studies show that in 1 the two P2 ligands are rectangularly oriented while in 2b, 2c, and 3 they are coupled to an acyclic, trapezoidally arranged P4 chain.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280617
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Formation and Structure of a New Dinuclear Rhodium Complex [(iPr3P)RhCl]2[P3C3tBu3] (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 737-739 
    Details
    ISSN: 0009-2940
    Keywords: Rhodium complex, dinuclear ; Phosphaalkyne ; Trimerization ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The new dinuclear rhodium complex 4 was synthesized by reaction of [(iPr3P)2RhCl]2 (1) or [(iPr3P)2(CH2=CH2)RhCl] (2) with 2-tert-butyl-1-phosphaacetylene (3) in 58% yield. An X-ray analysis reveals that in 4 a 1,3,6-triphosphahexadiene-1,6-diyl chain is bound to each of the two rhodium atoms in an η1,η3 manner.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280714
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Synthesis of Structures of (Acyloxy)boranesDedicated to Prof. Dr. A. Schmidpeter on the occasion of his 65th birthday.Synthesis of Structures of (Acyloxy)boranes (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 751-762 
    Details
    ISSN: 0009-2940
    Keywords: Trifluoroacyloxy-9-borabicyclo[3.3.1]nonane ; Pivaloyloxy-9-borabicyclo[3.3.1]nonane dimer ; Bis(9-borabicyclo[3.3.1]nonyl]oxalate ; Tetrakis(9-borabicyclo[3.3.1]nonyl)-dihydroxyoxalate ; Bis(9-borabicyclo[3.3.1]nonyl)-2,2-dimethylmalonate tetramer ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 9-Borabicyclo[3.3.1]nonane (9-BBNH) reacts with monocarboxylic acids to afford 9-(acyloxy)-9-borabicyclo[3.3.1]nonanes which are dimers in the solid state as shown by X-ray crystal structures of the benzoate and pivalate. More complex reactions were observed by allowing 9-BBNH to react with dicarboxylic acids in THF or monoglyme. Thus, (9-BBN)2 oxalate 3 contains a fully delocalized oxalate unit with equal C-O and B-O bond lengths. Traces of water convert it into the tetrakis(9-BBN) oxalate 5. A rather unusual structure is veryfied by 9-BBN 2,2-dimethylmalonate 7 which according to its molecular structure is a tetramer featuring a 32-membered ring system. In contrast, reactions of oxalic acid with thexylborane leads to reduction of the acid and formation of a bicyclic dioxaborolo-dioxaborolane 10. Several intermediates were detected by 11B-NMR spectroscopy as well as in reactions of BH3 · THF or BH3 · SMe2 with oxalic acid.  -  It follows from the present study that (acyloxy)boranes derived from dicarboxylic acids are strong Lewis acids with an unexpected variety of structural features.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280803
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    β-Alkoxy- and β-Hydroxyalkylphosphanes as Ligands in the Stereoselective Hydrogenation  -  A Comparison (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 767-773 
    Details
    ISSN: 0009-2940
    Keywords: Ether phosphanes ; Hydroxyalkylphosphanes ; Rhodium ; Asymmetric hydrogenation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Optically pure 1,4-bis(diphenylphosphanyl)-2-hydroxy-butane (2) and its methyl ether 1 can be conveniently prepared by starting from chiral pool substances such as malic or L-ascorbic acid. Different pathways to these compounds were elucidated. In one case an interesting migration of an acetalic OH-protective group was observed. The reaction of the bisphosphanes with Rh1 or PdII gave uniform metal complexes. On the basis of X-ray structural analysis, NMR and IR data it was concluded that in the investigated precatalysts of the type [Rh(COD)(bisphosphane)]BF4 a coordination of the alkoxy or hydroxy oxygen to the metal does not take place. Nevertheless, significant differences in enantioselectivity and activity could be observed when several prochiral substrates were hydrogenated.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280805
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Substituted Variants of the Cluster Type Fe3(CO)9(μ3-η2-RC≡N) (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 793-797 
    Details
    ISSN: 0009-2940
    Keywords: Triiron clusters ; Capping nitrile ligands ; Phosphine substitutions ; Structure determination ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Various aromatic nitriles were used for the preparation of the nitrile-capped clusters Fe3(CO)9(μ3-η2-RC≡N) (2) by reaction with Fe3(CO)12 under hydrogen. Electron-rich nitriles decrease, electron-poor nitriles increase the thermal stability of clusters 2. With CN-substituted pyridines only traces of clusters 2 could be obtained. CO replacement in Fe3(CO)9(PhCN) (2a) by isonitriles also causes a lowering of the stability. Conversely, more stable products were obtained by substitution reaction with trimethyl phosphite. One PPh3 and two dppm derivatives were also obtained. The structure of Fe3(CO)8-P(OMe)3(μ3-η2-PhC=N) (5a) was determined.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280809
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Zinc Complexes of Drugs Containing Nitrogen Heterocycles (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 779-785 
    Details
    ISSN: 0009-2940
    Keywords: Zinc complexes ; Drug ligands ; Captopril ; Isoniazid ; Nalidixic acid ; Mercaptopurine ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four drugs whose actions have a relation to the status of zinccontaining species in the human body were used as ligands in zinc complexes. Captopril (H2Cap) forms the compound [ZnCap] (1) presumed to be a coordination polymer with O and S coordination. Isoniazid, in the presence of zinc salts, is converted to 1,2-diisonicotinoyl hydrazide (H2Nih) which forms polymeric [Zn(Nih)NH3] (2) with trigonal-bipyramidal ZnO2N3 coordination. Nalidixic acid (HNal) and zinc perchlorate yield [Zn(HNal)2(H2O)2](ClO4)2 · 2 H2O (3) containing zinc in an octahedral ZnO6 environment. Mercaptopurine (H2Mer), in the presence of ammonia, forms [Zn(Mer)(NH3)2] . H2O (4) which is a coordination polymer containing tetrahedral ZnN4 units. The structures of [Zn(Nih)NH3], [Zn(HNal)2(H2O)2](ClO4)2 . 2 H2O, and [Zn(Mer)(NH3)2] . 2 H2O were determined diffractometrically.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280807
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Enantioselective Deprotonation of Benzyl Phosphates by Homochiral Lithium Amide Bases  -  Configurational Stability of Benzyl Carbanions with a Dialkoxyphosphoryloxy Substituent and Their Rearrangement to Optically Active α-Hydroxy Phosphonates (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 823-830 
    Details
    ISSN: 0009-2940
    Keywords: Phosphate-phosphonate rearrangement ; Carbanions, benzylic, configurational stability of ; Phosphonaes Lithium amides, homochiral ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Benzyl dialkyl phosphates are deprotonated enantioselectively by homochiral lithium amides of isopropyl(1-phenylethyl)amine or bis(1-phenylethyl)amine. The short-lived benzylic carbanions formed are virtually configurationally stable relative to the rearrangement to optically active phenyl-hydroxymethylphosphonates. The enantiomeric excesses are up to 50%. The pro-(S) hydrogen is removed by amides having (S) configuration. Homochiral diethyl (S)-phenyl[D1]-methyl phosphate [(S)-16c] is deprotonated by both LDA and n-BuLi with a high primary kinetic isotope effect (kH/D ≍ 50) and isomerizes to the corresponding α-hydroxy phosphonate with an enantiomeric excess of up to 85%.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280814
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Tris(1,10-phenanthroline)iron(II) Complexes  -  Broad Variation of the Redox Potential by 4,7-Substitution at the Phenanthroline Ligands[1] (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 845-850 
    Details
    ISSN: 0009-2940
    Keywords: Phenanthroline synthesis ; Tris(phenanthroline)iron(II) complexes ; Redox potential ; Cyclic voltammetry ; Electron transfer, outer-sphere ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The new 4,7-donor-substituted phenanthrolines 2a-h were synthesized and the corresponding tris(1,10-phenanthroline)iron(II) complexes 3a-h studied by cyclic voltammetry. In more detail three novel aza-crown ether-linked (phenanthroline)iron complexes were investigated, the redox potentials of which could be fine-tuned by the addition of group-Ia,IIa metal cations. All iron(II) complexes showed reversible waves at scan rates between 50 and 500 mV · s-1 and could be reversibly oxidized and reduced by chemical means.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280816
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Bis(cyclopentadienyl)methane-Bridged Dinuclear Complexes, 10Part 9: B. Stempfle, H. Werner, Gazz. Chim. Ital., 1995, 125, in press. The Bis(cyclopentadienyl)methane Link between Lewis Basic and Lewis Acidic Metal CentersDedicated to Prof. Dr. Herbert Schumann on the occasion of his 60th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 877-881 
    Details
    ISSN: 0009-2940
    Keywords: Bis(cyclopentadienyl)methane ; Heterobimetallic complexes ; Imido complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The mononuclear rhodium complexes [(C5H5CH2C5H4)-Rh(CO)2] (1) and [(C5H5CH2C5H4)Rh(PhC≡CPh)(PiPr3)] (2) readily react with nBuLi or TlOEt to yield the corresponding lithium salts 3 and 4 or thallium salts 5 and 6. The reaction of these salts with [(C5H5)Nb(NtBu)Cl2] (7) leads to the formation of the heterodinuclear compounds [{CH2(C5H4)2}-{Rh(CO)2}{(C5H5)Nb(NtBu)Cl}] (8) and [{CH2(C5H4)2}-{Rh(PhC≡CPh)(PiPr3)}{(C5H5)Nb(NtBu)Cl}] (9), respectively. Treatment of 3-6 with [Mo(NtBu)2Cl2] (10) gives the heterodinuclear Rh/Mo complexes [{CH2(C5H4)2}{Rh(CO)2}-{Mo(NtBu)2Cl}] (11) and [{CH2(C5H4)2}{Rh(PhC≡CPh)-(PiPr3)}{Mo(NtBu)2Cl}] (12). The analogous reaction of [Mo(NMes)2Cl2(DME)] (13) with 3-6 yields the corresponding complexes [{CH2(C5H4)2}{Rh(CO)2}{Mo(NMes)2Cl}] (14) and [{CH2(C5H4)2}{Rh(PhC≡CPh)(PiPr3)}{Mo(NMes)2Cl}] (15). From the monometallated ligand [(C5H5CH2C5H4)M] (M = Li: 16; M = Tl: 17) and the imidometal compounds 7, 10 and 13, the mononuclear complexes [(C5H5CH2C5H4)(C5H5)Nb-(NtBu)Cl] (18) and [(C5H5CH2C5H4)Mo(NR)2Cl] (R = tBu: 19; R = Mes: 20) have been obtained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280905
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Synthesis of 7-Alkyl/aryl-1,3,5-triaza-7-phosphonia-adamantane Cations and Their Reductive Cleavage to Novel N-Methyl-P-alkyl/aryl[3.3.1]bicyclononane Ligands (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 891-900 
    Details
    ISSN: 0009-2940
    Keywords: 1,3,5-Triaza-7-phospha-adamantane ; Reductive cleavage of phosphonium salts ; Ambidentate P,N-ligands ; P,N-[3.3.1]bicyclononane systems ; Phosphanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two reaction pathways for the synthesis of 1,3,5-triaza-7-phosphoniaadamantane salts, RP[(CH2)6N3]+X- (1), were followed. Route 1 starts with commercial tetrakis(hydroxymethyl)phosphonium chloride, which is converted into P(CH2OH)3 by treatment with a base. Subsequent quaternization with alkyl halides RX and cyclization with formaldehyde and ammonia afford [R-TPA]+X-. This process is only applicable for R = Me (1a) and Et (1b), however. Route 2 is more general and starts with primary phosphanes RPH2, which are converted into organotris(hydroxymethyl)phosphonium salts with formaldehyde and hydrochloric acid followed by ring closure with CH2O/NH3 to give compounds 1c-1f (R = t-Bu, c-Hex, Bz, and Ph, respectively, and X = Cl, I, PF6, or BPh4). Reductive cleavage of compounds 1 by sodium in liquid ammonia proceeds with either external (P-R) or internal (P-CH2) bond rupture. P-R cleavage affords the 1,3,5-triaza-7-phosphaadamantane (TPA), while cage cleavage leads to new bowl- or helmet-shaped ligand systems with peripheral amine and phosphane functions (2). Yields of the cage-opening reaction are highest for R = Ph (2f), moderate for R = Me and Et (2a, 2b), and poor with the remaining R groups (2c-2e). A radical mechanism is proposed for this reaction, the leaving group properties of R determining the direction of the cleavage. The crystal and molecular structures of compounds 2a and 2f were determined by X-ray diffraction studies. Exo positions were found for the N-Me and P-R groups. The isomers with the R group in the endo position are also present in solution in small amounts, as detected by NMR spectroscopy. Isomer interconversion by P inversion is slow on the NMR time scale. Compounds 2a, 2b and 2f were oxidized with elemental sulfur and selenium to give the monosulfides and selenides, respectively (2aS, 2aSe, 2bS, 2bSe, 2fS, 2fSe). Oxidation with H2O2 led to degradation. Compound 2a was quaternized at the P atom by treatment with Mel to give the corresponding phosphonium salt. Treatment with equimolar quantities of (Me2S)AuCl led to the 1:1 complexes 2aAucl, 2bAuCl and 2fAuCl, with the AuCl units solely P-bonded, as determined by X-ray diffraction of 2aAuCl and 2fAuCl. Compound 2a forms an ionic 2:1 complex with AuCl, composed of the ions [(2a)2Au]+ Cl- (with unidentate ligands), while its reaction with [Me2AuCl]2 leads to [Me2Au(2a)]+ [Me2AuCl2]- (with a chelating 2a ligand), as again confirmed by crystal structure analysis in both cases. Ligands 2a, 2b and 2f also act as chelating ligands in their tetracarbonylmolybdenum complexes obtained in the reactions with (C7H8)Mo(CO)4.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280907
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Metal Tetrahydroborates and Tetrahydroborato Metalates. 20Contribution 19: M. Bremer, H. Nöth, M. Thomann, M. Schmidt, Chem. Ber. 1995, 128, 455-460.. Reactions of Cadmium Tetrahydroborate with Alcoholates and Phenolates - X-ray Structure of [MeCd(OCMe3)]4 (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 923-927 
    Details
    ISSN: 0009-2940
    Keywords: 11B-NMR spectroscopy ; 113Cd-NMR spectroscopy ; tert-Butoxy(methyl)cadmium tetramer ; Organyloxy(tetrahydroborato)cadmates ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cadmium tetrahydroborate reacts with alkali metal alcoholates or phenolates in THF solution either with formation of addition products [Cd(BH4)2OR]- or by ligand exchange to produce Cd(BH4)OR. Different oligomers of the latter are formed depending on concentration. The reaction of Cd(BH4)2 with Cd(Omes)2 (mes = mesityl) leads to an equilibrium of the starting materials with Cd(BH4)(Omes) as shown by 113Cd-NMR spectroscopy. The crystal structure of Me-Cd(OCMe3), a molecule which can be regarded as a model for Cd(OCMe3)(BH4), proved to be a tetramer with a cubane-type Cd4O4 core.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280912
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Preparation, Properties, and Reactions of Metal-Containing Heterocycles, XCIPart XC: Ref.[1]. Insertion of Activated Alkynes and Sulfur into the P-P Bond of DiphosphamolybdacyclopropanesDedicated to Professor Herbert Schumann on the occasion of his 60th birthday (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 973-982 
    Details
    ISSN: 0009-2940
    Keywords: Molybdenum heterocycles ; P - P bonds ; Activated alkynes ; Sulfur ; Insertion reactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The insertion of the alkynes ZC≡CZ (2a-i) [Z = Co2R: R = Me (a), Et (b), nPr (c), iPr (d), nBu (e), tBu (f), neo-Pent (g), cyc-Hex (h); Z = CF3 (i)] into the P1-P2 bond of the diphos-phamolybdacyclopropane Mes (1) (Mes = 2,4,6-trimethylphenyl) results in the formation of the diphosphamolybdacyclopentenes Mes (3a-i). According to an X-ray structural analysis, 3a crystallizes in the space group P21/c with the mesityl function at P2 and the cyclopentadienyl fragment at the metal atom on the opposite side of the planar five-membered ring. The same orientation is found in solution by NMR experiments (NOE; 2D 1H, 13C HETCOR). Kinetic investigations confirm that the rate constants decrease in the sequence R = Me 〉 Et 〉 nPr 〉 isoProp 〉 Cy 〉 nBu 〉 neo-Pent 〉 tBu. The second-order reaction and the strongly negative activation entropy which was determined in the case of the reaction 1 + 2e → 3e are consistent with a nucleophilic attack of P2 at one of the triply bonded carbon atoms of the alkyne. The reaction of 3a, h with sulfur affords the diastereomeric compounds Mes (4a, h). An X-ray structural analysis of the heterocycle 4h, which crystallizes in the space group P1, shows the presence of the enantiomeric pair SR/RS. The reaction of 1 with alkynes is hindered if this heterocycle is oxidized by sulfur to give Mes (5). Further reaction of 5 with sulfur leads to the ring-expanded heterocyclic intermediate (6) which crystallizes in the space group P1. The five-membered ring in 6 has an envelope conformation. Upon thermally induced cleavage of the P2S2Mes fragment from 6 the three-membered ring (7) is formed as the final product.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281003
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Correction (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1271-1271 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281221
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Metal Complexes of Functional Isocyanides, XXV. Amino(hydrazino)carbene Complexes (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1061-1068 
    Details
    ISSN: 0009-2940
    Keywords: N-Isocyanides ; N-Isocyanodialkylamine complexes ; Carbene complexes ; Imaging-Plate data collection ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The N-isocyanodialkylamine metal complexes [M(CO)5CN-NR2] (M = Cr, W), trans-[MI2(CNNR2)2] (M = Pd, Pt), trans-[Pt(Cl)(CNNR2)(PPh3)2]BF4, and cis-[PtCl2(CNNR2)(PPh3)] [R = Et, iPr; 2 R = -{CHMe(CH2)3CHMe}-] react with primary amines to give the amino(hydrazino)carbene metal complexes [M(CO)5(C(NHR′)NHNR2}] (R′ = Me, nPr, Cy) (1-9), trans-[PtI2{C(NHMe)NHNR2}2] (10-12) and trans, and the amine adducts cis-[PtCl2{C(NHMe)NHNC(H)(Me) (CH2)3CHMe}(PPh3)] H2NMe (14), and trans-[PdI2{C (NHMe)NHNC(H)(Me)(CH2)3CHMe}2] 2 H2NMe (15). With secondary amines the amino(hydrazino)carbene metal complexes trans (18) and trans-[PtCl{C(NEt2)NHNEt2} (PPh3)2]BF4 (19) Were isolated. The complexes trans-[PtI2{C(NHCy)NHNiPr2}CNNiPr 2] (20) and trans-[PdI2 (NH2Cy){C(NHCy)NHNiPr2}] (21) were obtained by reaction of trans-[MI2(CNNiPr2)2] (M = Pd, Pt) with cyclohexylamine. The structures were assigned on the basis of IR, NMR- (1H, 13C, 31P), and mass spectroscopy as well as an X-ray structural analysis of 21.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Metallocenophanes, VIIPart VI: Ref.. Preparation and Characterisation of the Disilver(I) Complexes of Conjugated Polyenes with [2.2.2]Paracyclophanyl End Groups (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1079-1082 
    Details
    ISSN: 0009-2940
    Keywords: [2.2.2]Paracyclophanes ; Polyenes ; Silver complexes ; X-Ray structural analysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of the disilver(I) complexes 3 and 4, polyene metal complexes that are terminally substituted with [2.2.2]paracyclophanyl units, is described. NMR spectro-scopic studies on the disilver perchlorate complex 3b showed that (a) the sites of complexation are the cyclophane groups and (b) the olefinic spacers do not overly perturb the overall complexation properties of the individual [2.2.2]paracyclo-phanyl groups. The crystal structures of the disilver hexafluo-roantimonate complexes 4a-b were determined. The use of the hexafluoroantimonate counterion and solvent mixtures containing toluene both proved crucial in obtaining single crystals; toluene is incorportated into the crystal lattices.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281104
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Highly Substituted Tris(pyrazolyl)methane Ligands and Some Zinc Complexes Thereof (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1095-1103 
    Details
    ISSN: 0009-2940
    Keywords: Zinc complexes ; Tridentate ligands ; Tris(pyrazolyl)methane ; Reactivity ; Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Tris(pyrazolyl)methane ligands in which two or three of the pyrazole carbon atoms bear organic substituents (L1-L7) were synthesized from chloroform and the corresponding pyrazole under phase transfer conditions. Their behavior towards zinc salts was found to span the range from no reaction at all to hydrolytic destruction. One hydrolysis product isolated and structurally characterized was the perchlorate complex [(HPz5)3Zn-OClO3]ClO4 (1), other ones were the 2:1 complexes (HPz3)2ZnBr2 (2) and (HPz6)2Zn(NO3)2 (3, HPzn = substituted pyrazole). Zinc perchlorate and tris(trimethylpy-razolyl)methane (L2) formed the octahedral binary complex [L22Zn](ClO4)2 (4) as evidenced by a structure determination. Zinc halides produced the 1:1 complexes L1 · ZnBr2 (5), L4 · ZnCl2 (6), and L4 · ZnBr2 (7), which according to the structure determinations of 6 and 7 contain tetrahedral ZnN2Hal2 units with only bidentate tris(pyrazolyl)methane ligands. In contrast, the zinc nitrate complex L4 · Zn(NO3)2 (8) was found to have an octahedral structure with mono- and bidentate nitrate and tridentate L4. The bromide complex 7 was converted by silver perchlorate hydrate into the labile compound [L4 · ZnBr]ClO4 (9) and then into the unstable product [L4 · Zn-OH2](ClO4)2 (10), both presumed to contain zinc in a tetrahedral ZnN3Br or ZnN3O environment, respectively. The ease of hydrolytic self-destruction prevented the exploitation of the reactivity of 9 and 10 in analogy to that of the corresponding tris(pyrazolyl)borate zinc complexes.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    The 13C Chemical Shift of the ipso Carbon Atom in Phenyllithium (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1183-1186 
    Details
    ISSN: 0009-2940
    Keywords: Phenyllithium ; Solid-state NMR ; Chemical shift anisotropy ; Calculations, IGLO ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phenyllithium was labeled with 6Li and 13C at the ipso carbon atom, and the tetramer was measured by solid-state NMR. The chemical shift tensor data were obtained by a moment analysis of the spinning side bands and were compared with the results obtained by calculations with the IGLO method. Although no splitting by dipolar spin coupling to 6Li was found the very good agreement between IGLO predictions and experimental results allowed alignment of the tensor axis to the molecular frame and interpretation of the data. The large deshielding of the isotropic chemical shift is mainly due to a decrease of the ΔE term in s̰.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281208
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Synthesis and Characterization of Copper(II) Complexes of a 14-Membered cis-N2S2 Dibenzo Macrocycle and of Its Bis-acetato and Bis(methylpyridyl) Derivatives (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1199-1205 
    Details
    ISSN: 0009-2940
    Keywords: Copper(I) complexes ; Copper(II) complexes ; N,S-Donor ligands ; Macrocyclic ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis and characterization of seven copper coordination compounds with the 14-membered macrocyclic cis-N2S2 dibenzo ligand 6,7,13,14,15,16,17,18-octahydrodibenzo[e,m]-[1,4,8,11]dithiadiazacyclotetradecine (L1) and its N,N'-bisacetato and -bis(methylpyridyl) functionalized derivatives H2L2 and L3 are described. The structures of five compounds were determined by single-crystal X-ray diffraction. The tetrahedrally distorted square-planar coordination geometry of [CuL1](ClO4)2 (1) changes upon reduction of copper to a severely distorted tetrahedral geometry in [CuL1]Br · MeCN (2). The Cu-N bond lengths increase from 1.988(3) to 2.029(5) Å; the Cu-S bond lengths decrease from 2.293(1) to 2.255(2) Å. Copper(II) is hexacoordinated in [CuHL2]HSO4 · 2.5 H2O (5) and [CuHL2]ClO4 · H2O (6). Both compounds exhibit very similar overall structures in the cationic part. The macrocyclic ring of the ligand is folded along an N⃜S axis, the octahedral geometry is strongly Jahn-Teller distorted, with O and S donor atoms in the apical positions. Compound 5 contains one very short [2.271(3) Å] and one long [2.701(3) Å] Cu-S (thioether) bond. In [CuL3](ClO4)2 · 2 H2O (7) one thioether group of the ligand L3 remains uncoordinated. The coordination polyhedron is rather irregular: Cu-S 2.506(3) and Cu-N 1.960(7)-2.107(8) Å. The compounds were further characterized by electronic and EPR spectroscopy and by cyclic voltammetry. Some relationships to the structural and spectroscopic properties of “blue” copper proteins were found.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281211
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Chiral Ligands for Transition Metal Complexation (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 449-454 
    Details
    ISSN: 0009-2940
    Keywords: Chiral ligands ; Transition metal complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Novel chiral salen- or salphen-type ligands with stereogenic centres in the 1,3-dicarbonyl moiety 2 as well as in the amino bridge in 15-18 were synthesized from the enantiomerically pure Hajos-Wiechert ketone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280503
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Synthesis and Characterization of β-Phosphaenones An Investigation on the Conjugative Properties of the P=C Bond (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 465-476 
    Details
    ISSN: 0009-2940
    Keywords: Phosphaalkenes, C-halo, C-metal ; Phosphaacrylic acid ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermally and air-stable β-phosphaenones were synthesized by functionalization of Mes*P=CCl2 (1; Mes* = supermesityl = 2,4,6-tri-tert-butylphenyl). At low temperature, 1 was lithiated by halogen-metal exchange with n-butyllithium to give the phosphanylidene carbenoid (Z)-Mes*P=C(Cl)Li [(Z)-2] which reacted with acid chlorides to furnish the C-carbonyl-substituted phosphaalkenes (Z)-Mes*P=C(Cl)R (3: P = COtBu; 4: R = COPh; 5: R = COOEt). The reaction of (Z)-2 with carbon dioxide furnished the carboxylate 6, which was converted by treatment with pivaloyl chloride or trimethylsilyl chloride into the phosphaalkenes 7 and 8 functionalized at the carbon atom by an anhydride or a trimethylsilyl ester function, respectively. Acidification of 6 or hydrolysis of 8 with water in chloroform solution afforded the novel carboxylic acid (Z)-Mes*P=C(Cl)COOH (9). Spectroscopic investigations (NMR, UV, IR) of 3-9 and the X-ray structures of 3 and 4 are presented. Based on these properties and on theoretical calculations, the occurrence of conjugation in the β-phosphaenone system is discussed and compared with the well-known conjugation in normal enones.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280506
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Reactions of Phosphaalkenes with HexafluoroacetoneDedicated to Professor H. M. R. Hoffmann on the occasion of his 60th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 499-502 
    Details
    ISSN: 0009-2940
    Keywords: Phosphaalkenes ; Cycloadditions ; Insertion reactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dimethylamino-substituted phosphaalkene 1 reacts with hexafluoroacetone (HFA) with addition at the P=C bond to form the 1,5,2-dioxaphosphorinane 2. The structure of 2 was confirmed by an X-ray crystal structure analysis. The six-membered ring displays an envelope conformation with the phosphorus atom out of the plane, but the phosphorus is disordered over two sites. Reaction of P-trimethylsilyl-substituted phosphaalkenes with HFA proceeds with retention of the P=C double bond and insertion of HFA into the P—Si bond. Two isomeric products are obtained and are characterized by 1H-, 13C-, 19F-, and 31P-NMR spectroscopy, IR spectroscopy, mass spectrometry, and elemental analysis.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280511
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Zinc Complexes of S,N Ligands Derived from Thiazolines (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 787-791 
    Details
    ISSN: 0009-2940
    Keywords: Zinc complexes ; Sulfur and nitrogen ligands ; Structure determinations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three different thiazoline derivatives or their tautomeric mercaptoethylamine derivatives were used for the preparation of zinc complexes containing S,N ligands. 2-(2-pyridyl)-3-(2-pyridylmethyl)-1,3-thiazolidine (PPMT) could not be opened reductively but acted as a tridentate nitrogen ligand in (PPMT)ZnX2 (1a, b, X = Br, NO3). The thiazolidine tautomer N-(2-mercaptoethyl)salicylideneimine (MESIH2) yielded polymeric (MESI)Zn (2) and, after oxidation, monomeric (MESI)2Zn (3) containing a disulfide unit. The 2-aryl-benzo-1,3-thiazoline tautomers N-(2-mercaptophenyl)-p-fluoroben-zylideneimine (MPFBH) and N-(2-mercaptophenyl)-p-meth-oxybenzylideneimine (MPMBH) underwent reaction with diethyl zinc resulting in the unstable L . Zn-Et complexes 4a and b, which are probably dimeric and the stable 2:1 complex (MPFB)2Zn (5). The structures of 3 and 5 were determined and were found to exhibit distorted tetrahedral ZnN2O2 and ZnN2S2 coordinations, respectively.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280808
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Synthesis and Reactivity of Silicon-Transition Metal Complexes, 3l30. Mitteilung: Lit.[1e].. Metallosilanols and Metallosiloxanes, 61.-5. Mitteilung: Lit.[1a-e].. Die ersten Hydroxysilandiyl-verbrückten Zweikernkomplexe: Selektive Oxygenierung der Silicium-Brücke in Silandiyleisen-Komplexen mit Dimethyldioxiran (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 963-965 
    Details
    ISSN: 0009-2940
    Keywords: Dimethyldioxirane ; Oxofunctionalization ; Si-H bonds ; Iron complexes, silanediyl-bridged ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Reactivity of Silicon-Transition Metal Complexes, 31  -  Metallosilanols and Metallosiloxanes, 6.  -  The First Hydroxysilanediyl-Bridged Binuclear Complexes: Selective Oxofunctionalization of the Silicon Bridge in Silanediyliron Complexes with DimethyldioxiraneOxygenation of [μ-(R)(H)Si][Fe(CO)2Cp]2 [R = Me (1a), pTol (1b)] with dimethyldioxirane (2) yields the μ-(hydroxysilanediyl)bisiron complexes [μ-(R)(HO)Si][Fe(CO)2Cp]2 [R = Me (3a), pTol (3b)]. In an analogous manner the cyclic complex (μ-OC)[μ-(Mes)(H)Si][Fe(CO)Cp]2(Fe-Fe) (6) obtained by photochemical reaction of Cp(OC)2Fe-Me (4) with MesSiH3, (5) is converted into (μ-OC)[μ-(Mes)(HO)Si][Fe(CO)Cp]2-(Fe-Fe) (7). 6 and 7 are obtained as a mixture of cis(Mes), cis(H or OH), and trans isomers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280920
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Organophosphorus Compounds, 103Part 102: Ref.[1]. Thermal Transformation of Kinetically Stabilized Phosphaalkynes with Phosphinidene Precursors. Synthesis of Phosphorus-Carbon Cage Compounds by Cocyclooligomerization ProcessesDedicated to Professor H.-J. Bestmann on the occasion of his 70th birthday (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 991-997 
    Details
    ISSN: 0009-2940
    Keywords: Phosphaalkynes ; Phosphinidenes ; Phosphinidene Complexes ; Cocyclooligomerization ; Cage compounds, phosphorus-carbon ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phosphaalkynes 2 undergo cocyclooligomerization reactions with the phosphinidene 14 or the phosphinidene-W(CO)5 complex 18 to furnish the phosphorus-carbon cage compounds 16 or 23. The phosphinidene 14 is generated by the thermal reaction of 2a-c with the phosphole 11, a process in which the initially formed 7-phosphanorbornadienes 12a-c decompose to the λ3-phosphinines 13a-c and the desired reactive intermediate. When three further equivalents of the phosphaalkynes 2a-c are employed, the tetraphosphahomoquadricyclanes 16a-c can be isolated in 53-65% yields. The second approach is based on the thermal fragmentation of 17 to generate the phosphinidene-W(CO)5 complex 18 which, in turn, reacts with four equivalents of the phosphaalkynes 2a or b to produce the pentaphosphadeltacyclanes 23a or b. The constitutions of these novel phosphorus-carbon cage compounds were confirmed by X-ray crystal structure analyses of 16a and 23a.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281006
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Masthead (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Chiral Carbanions, 1. Configurational Stability and Reactions of α-Acyloxy-Substituted α-Methylbenzyllithium Compounds (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1069-1077 
    Details
    ISSN: 0009-2940
    Keywords: Esters, 1-phenylethyl ; Carbanions, α-methyl-α-oxybenzyl, Configurational stability ; Ester - hydroxy ketone rearrangement ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Racemic and optically active 1-phenylethyl esters of pivalic, ( - )-camphanic and 2,4,6-triisopropylbenzoic acid were prepared. The esters 7a of pivalic acid were deprotonated with lithium 2,2,6,6-tetramethylpiperidide (Li-TMP) to form α-oxy-α-methylbenzyllithium compounds which are partly con-figurationally stable prior to acylation with starting material. Camphanic ester (-)-7b cannot be deprotonated by Li-TMP and tBuLi is added to the ester function to afford ketone (-)-12a. 1-Phenylethyl 2,4,6-triisopropylbenzoates 16 were transformed within minutes to carbanions 19 by using sBuLi/TMEDA in THF, hexane, toluene and sBuLi without TMEDA in toluene/20% diethyl ether at -78°C. The carbanions are configurationally stable only in toluene/20% diethyl ether and racemise partly in the other solvents. They react with a variety of electrophiles with either retention [MeOD, AcOD, (MeO)2CO, CICO2Me] or inversion (Me3SnCl) of configuration. Carbanions 19 rearrange on warming to -20°C to hydroxy ketone 24 with racemisation.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281103
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Metal Complexes with Tetrapyrrole Ligands, LXIX. Facile Synthesis and 13C-NMR Spectrum of Dichloro(octaethylporphyrinato)zirconium(IV) (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1131-1133 
    Details
    ISSN: 0009-2940
    Keywords: Zirconium(IV) octaethylporphyrin complex ; Dichlorozirconium(IV) porphyrin complex ; Precursor of organometallic compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of dichloro(2,3,7,8,12,13,17,18-octaethylpor-phyrinato)zirconium(IV), Zr(oep)Cl2, from zirconium tetrachloride and octaethylporphyrin, H2(oep), is described. The reported synthesis is a new and simple route to this precursor of organometallic compounds. Zr(oep)Cl2 was characterized by elemental analyses, 1H- and 13C-NMR, UV/Vis, and mass spectra. Hydrolysis yielded a mixture of mono- and binuclear hydroxy zirconium(IV) porphyrins.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281112
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Auf- und Abbau von Azadecaboranen; Aza-nido-nonaboratFrau Professor Marianne Baudler zum 75. Geburtstag gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1221-1224 
    Details
    ISSN: 0009-2940
    Keywords: 10-Organo-10-aza-nido-nonaborates ; 6-Alkylamine-4-aryl-4-aza-arachno-nonaboranes ; 1-Orgaro-1-aza-closo-decaboranes ; 6-Aryl-6-aza-nido-decaboranes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Degradation of Azadecaboranes; Aza-nido-nonaborateThe boranes arachno-B9H13(NRH2 (1a-c: R = p-ClC6H4, p-MeC6H4, PhCH2) are dehydrogenated at 140°C to give nido-RNB9H11 (2a-c), from which the azaboranes closo-RNB9H9 (3a-c) are formed on further dehydrogenation at 460°C. These azaboranes are deboronated either by the attack of the amine iPrNH2 or by one of the fluorides [NBu4]F or [S(NMe2)3][Me3SiF2] in THF. One of the four boron atoms adjacent to nitrogen in the closo species is removed and then detected in the borazine (HNBiPr)3 or the borate BF4, respectively, whereas the novel anions nido-RNB8H9 (4a-c) remain. The structure of 4a-c corresponds to that of nido-SB8-H9-, according to NMR spectra. Primary amines R'NH2 deboronate the closo-boranes 3a, b in a solvent less polar than THF to give the amine - azanonaboranes arachno-RNB8H10-(NR'H2) (5a-c: R' = iPr, Pr, Bu). The nido product [iPrNH3][(p-ClC6H4)NB8H9 is converted into a mixture of the arachno products 5a and (p-ClC6H4)NB8H10(NPrH2) (5d) by the action of PrNH2, making plausible that anions of type 4 are intermediates during the transformation of 3 into 5.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281213
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Thermische Stabilisierung des Silaethens Ph2Si=C(SiMe3)2Frühere Mitteilungen: Lit.Herrn Prof. Dr. Manfred Regitz zum 60. Geburtstag gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1241-1250 
    Details
    ISSN: 0009-2940
    Keywords: Methyl and phenyl group migrations in Ph2Si=C(SiMe3)2 ; Silaethenes Me2Si=C(SiMePh2)(SiMe3), PhMeSi=(SiMe2Ph)(SiMe3), Me2Si=C(SiMe2Ph)2 ; Silaethene dimers ; Disilaindanes ; Silaethene reactions with Et2O and with Ph2SiBr-CLi(SiMe3)2 ; Insertions of silaethenes into SiN bond of Ph2C=N-SiMe3 ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermal Stabilization of the Silaethene Ph2Si=C(SiMe3)2Frühere Mitteilungen: Lit. Herrn Prof. Dr. Manfred Regitz zum 60. Geburtstag gewidmet.Silaethene Ph2Si=C(SiMe3)2 (3) (generated from Ph2SiBr-C-Li(SiMe3)2 = 3 · LiBr in Et2O at -78·C) reversibly isomerizes fast by methyl migration, then a bit slower by phenyl migration, and finally fast by methyl migration into thermodynamically more stable Me2Si=C(SiMePh2)(SiMe3) (3a), then into medium stable PhMeSi=C(SiMe2Ph)(SiMe3) (3b), and finally into most stable Me2Si=C(SiMe2Ph)2 (3c) (cf. Schemes 1 and 2; Figure 1). Simultaneously with isomerization 3a · 3c [2 + 2] cycloadditions (dimerizations) of 3a and 3c occur (formation of 3a · 3a, 3a · 3c, 3c · 3c; cf. Scheme 2). Over and above that, silaethenes 3a and 3c irreversibly isomerize into disilaindanes 4a, 4b, and 4c (cf. Scheme 6). Certainly, the latter reactions are even slow at 100·C. Thermolysis of 3a · 3a, 3a · 3c, 3c · 3c at 340·C, on the other hand, leads by way of [2 + 2] cycloreversion and the intermediate formation of an equilibrium mixture of 3, 3a, 3b, 3c almost quantitatively to 4. In addition to the thermolysis products mentioned above, products of 3 and its isomers 3a, 3b, 3c with the solvents (for example Et2O; cf. Scheme 7), with the silaethene sources (for example 3 · LiBr; cf. Scheme 8), or with products formed from sources besides silaethene 3 (for example Ph2,C=N-SiMe3;cf. Scheme 4) are observed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281216
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    (η8-Cyclooctatetraene)(η4-1,2- and -1,3-diphosphacyclobutadiene)titanium: Preparation, Structure, and Reactivity (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 1261-1265 
    Details
    ISSN: 0009-2940
    Keywords: (Cyclooctatetraene)titanium complexes ; Diphosphacyclobutadiene ; Cyclodimerization ; Phosphaalkyne ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of the (η8-cyclooctatetraene)(η4-1,3- and -1,2-diphosphacyclobutadiene)titanium complexes 3a-c and 4a, b by cyclodimerization of the phosphaalkynes 2a-c [a: R = tBu, b: R = adamantyl (ad), and c: R = (iPr)(Me3Si)N] in the coordination sphere of the (η8-cyclooctatetraene)titanium complex 1 is described. The molecular structures of 3a-c and 4a, b were determined by spectroscopic methods (31P, 1H, and 13C NMR). In the case of 3a and 4a, X-ray analyses were carried out. The increased reactivity of 4a compared to 3a was utilized to separate 3a from 4a. Displacement of the 1,2-diphosphete (isolated as its cyclodimer 5) from 3b was achieved by reaction with hexachlorethane.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951281219
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Synthese und Komplexchemie funktionalisierter Tripod-Liganden RC(CH2PPh2)3Manfred Ziegler zum Gedenken. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 63-70 
    Details
    ISSN: 0009-2940
    Keywords: Tripod ligand synthesis ; Tripod nickel chloro complexes ; Tripod iron tris(acetonitrile) complexes ; Tripod cobalt acetate complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Complex Chemistry of Functionalised Tripod Ligands RC(CH2PPh2)3Malonic ester 1 is alkylated and converted into the triols RC(CH2OH)3 (5). These are easily converted into the corresponding functionalised tripodal ligands RC(CH2PPh2)3 (7) with R = Bzl (a), n-C12H25 (b), (CH3)2CH(CH2)2 (c). Crystals suitable for X-ray crystallography have been obtained of the ligand 7a. In addition, the tripod ligands 7a and 7c have been further characterized by the syntheses and X-ray analyses of the nickel complex [(7a)NiCl] (8a), the iron complex [(7c)Fe(NCCH3)3](BF4)2 [9 · (BF4)2], and the cobalt complex [(7c)Co{O(O)CCH3}](BPh4) (10 · BF4).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280109
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Übertragung eines cyclo-E5-Liganden (E = P, As) von einem Eisen- auf ein Ruthenium- und ein Osmium-ZentrumHerrn Professor Hubert Schmidbaur zum 60. Geburtstag gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 71-73 
    Details
    ISSN: 0009-2940
    Keywords: cyclo-E5 ligands (E = P, As) ; Transfer reaction ; Iron complexes ; Ruthenium complexes ; Osmium complexes ; Sandwich complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Transfer of a cyclo-E5 Ligand (E = P, As) from an Iron to a Ruthenium and an Osmium Center⋆The thermolysis of [Cp*Fe(η5-E5)] (1) and [{Cp*M(CO)2}2] (2, 3) affords by cyclo-E5 transfer the sandwich complexes [Cp* M(η5-E5)] (4a, b: M = Ru, E = P, As; 4c: M = Os, E = P). The crystal-structure analysis of [(C5Me4Et)Os(η5-P5)] (4c') confirms its sandwich-type structure.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280110
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Structural Chemistry of Lithium HydrazidesDedicated to Professor Ernst Biekert on the occasion of his 70th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 105-113 
    Details
    ISSN: 0009-2940
    Keywords: Lithium N,N'-diethylhydrazide hexamer ; Dilithium N,N'-bis(trimethylsilyl)hydrazide tetramer ; [Lithium N,N-bis(trimethylsily)hydrazide]-[dilithium N,N'-bis(trimethylsilyl)hydrazide] dimer ; Dilithium N-phenyl-N-trimethylsilylhydrazide tetramer ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Deprotonation of NH protons, of four diorgano-, organo(trimethylsilyl)- and bis(trimethylsilyl)hydrazines by n-butyllithium in hexane led to the following lithium hydrazides: [Et-(Li)N-N(H)Et]6, (1)6, [Me3Si(Li)N-N(Li)SiMe3]4, (2)4, [Me3Si-(Li)N-N(Li)SiMe3 · (Me3Si)2N-N(Li)SiMe3]2 (3)2, and [Ph-(Li)N-N(Li)SiMe3]4, (4)4, respectively. The structure determination by X-ray methods at low temperature reveals butterfly-shaped Li2N2 structural monomeric units which associate through “laddering” to the observed oligomers thereby generating penta- and hexacoordinated Li centers. N-N bonds lengths of up to 1.556 Å suggest that negative charge accumulates at the nitrogen atoms of (1)6, (2)4, and (3)2. An amazing structure shows the red compound 4 where two Li ions are π-sandwiched between two phenyl groups each. The compound can be looked at as a new type of a lithium lithiate complex, Li2[Li6N8Ph4(SiMe3)4], but short N-C and N-N bonds in the Li6N8 core indicate that its negative charge is transferred to the phenyl groups.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280204
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Ion Pair Charge-Transfer Complexes of Dithiolene Metalates with Diquaternary 2,2′-BiimidazolesDedicated to Professor Dr. Heinz Dürr on the occasion of his 60th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 131-136 
    Details
    ISSN: 0009-2940
    Keywords: Dithiolene metalates ; Biimidazolium dications ; Charge-transfer complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cycloalkylated biimidazolium dications (A2+) of reduction potentials from -0.4 to -1.4 V form ion pair charge-transfer complexes {A2+ [M(mnt)2]2-} with dithiolene metalates, M = Zn, Ni, Pd, Pt, mnt2- = maleonitrile-2,3-dithiolate. X-ray analyses of {P2BBIm2+[Ni(mnt)2]2-} [P2BBIm2+ = 1,1′,3,3′-bis(propane-1,3-diyl)bibenzimidazolium] and {B2Blm2+ [Pd(mnt)2]2-} [B2BIm2+ = 1,1′,3,3′-bis(butane-1,4-diyl)biimidazolium] reveal that the solid-state structure is largely determined by the geometry of the acceptor. When the latter is strongly twisted, the usually observed mixed donor-acceptor columns are modified to a chain-like arrangement. In the case of the bibenzimidazolium dication P2BBIm2+ the otherwise planar [Ni(mnt)2]2- becomes tetrahedrally distorted. By the application of the Hush model a reorganization energy of about 67 kJ/mol is estimated for the thermal electron transfer from [M(mnt)2]2- to A2+ when M = Ni, Pd, Pt, but considerable deviations from this model are observed when M = Zn. Irradiation of the free biimidazolium acceptors in the presence of EDTA affords the strongly reducing radical cations which reduce water to hydrogen in the presence of colloidal platinum. Attempts to sensitize this reaction by irradiating into the charge-transfer band of {A2+ [M(mnt)2]2-} have failed until now. The molar absorptivity of one biimidazolium radical cation is measured by spectroelectrochemistry.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280208
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Synthesis of Transient Silenes by a Modified Peterson Reaction (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 143-149 
    Details
    ISSN: 0009-2940
    Keywords: Silenes ; Silene dimerization ; 1,2-Disilacyclobutanes ; 2,3-Disilanaphthalene, tetrahydro- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Tris(trimethylsilyl)silylmagnesium bromide, obtained in situ from tris(trimethylsilyl)silyllithium and magnesium bromide, reacts with acetone, pivalaldehyde, or 2,4,6-trimethylbenzaldehyde to give the (1-hydroxyalkyl)tris(trimethylsilyl)silanes (Me3Si)3SiC(OH)Me2 (1a), (Me3Si)3CH(OH)tBu (1b), and (Me3Si)3SiC(OH)Mes (1c), resp. After deprotonation with methyllithium in ether at -78°C 1a-c eliminate trimethylsilanolate according to a modified Peterson mechanism to form transient silenes (Me3Si)2Si=CR1R2 (6a: R1 = R2 = Me; 6b: R1 = H, R2 = tBu; 6c: R1 = H, R2 = Mes). In the absence of trapping agents these silenes dimerize, 6a leading to the linear dimer 1-isopropenyl-2-isopropyl-1,1,2,2-tetrakis(trimethylsilyl)disilane (7) and 6b giving the head-to-head cyclodimerization product (E)-3,4-di-tert-butyl-1,1,2,2-tetrakis(trimethylsilyl)-1,2-disilacyclobutane (8), whereas 6c in a very unusual cyclodimerization step affords (E)-1,2,3,8a-tetrahydro-1-mesityl-5,7,8a-trimethyl-2,2,3,3-tetrakis(trimethylsilyl)-2,3-disilanaphthalene (9). Compound 9 is the result of an unexpected [2 + 4] reaction, in which the silene formally acts as the monoene and - involving the aromatic substituent - simultaneously also as the diene. The reaction of 1a-c with methyllithium in THF at low temperature initiates 1,3-Si,O-trimethylsilyl migrations leading to (trimethylsiloxy)-[bis(trimethylsilyl)silyl]alkanes (Me3Si)2SiH-CR1R2OSiMe3 3a-c. Reaction of 1a-c with an excess of methyllithium, tert-butyllithium, or phenyllithium, leads to trisilanes (Me3Si)2-SiR3-CHR1R2 11a-e, formed by the addition of the organolithium reagent to the Si=C bond of the transient silences 6a-c. Deprotonation of 1b and 1c in the presence of 2,3-dimethyl-1,3-butadiene gives the [2 + 4] cycloadducts 6-tert-butyl-3,4-dimethyl-1,1-bis(trimethylsilyl)-1-sila-3-cyclohexene (12a) and 6-mesityl-3,4-dimethyl-1,1-bis(trimethylsilyl)-l-sila-3-cyclohexene (12b). For 8 and 9 the results of the X-ray analyses are given.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280210
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Platin(II)-Komplexe mit Porphyrinliganden: Synthese und Synergismen bei der photodynamischen Tumortherapie (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 173-181 
    Details
    ISSN: 0009-2940
    Keywords: Porphyrins ; Platinum(II) complexes ; Photodynamic therapy ; Antitumor activity ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Platinum(II) Complexes with Porphyrin Ligands: Synthesis and Synergisms in the Photodynamic Tumor TherapyTwelve porphyrin ligands (2-5, 8, 13-16, 19, 27, 28) and their platinum(II) complexes (29-40) were synthesized and characterized. Nine of the porphyrins are derived from hemin, and three are based on tetraphenylporphyrin. The ligands were transformed into diammine-dicarboxylatoplatinum(II) complexes and diamine-dichloroplatinum(II) complexes. The antitumor activity in the photodynamic therapy of the ligands and their complexes was tested in vitro towards the MDA-MB-231 mammary carcinoma cell line. The results obtained showed an additive effect of the photodynamic activity of the porphyrin skeleton when irradiated with visible red light and the cytotoxic activity of the platinum moiety in the complexes.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280215
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Zwei Extreme in der Zinnchemie: Ein nichtbindender Sn-Sn-Abstand von 285 pm und eine 119Sn-NMR-Verschiebung δ = 3301 in metallorganischen Derivaten von Sn(0)Herrn Prof. Dr. G. P. Schiemenz gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 187-191 
    Details
    ISSN: 0009-2940
    Keywords: Tin complexes ; Transition metal complexes ; NMR, 119Sn ; Sn(0) compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two Extremes in Tin Chemistry: A Non-bonding Sn-Sn Distance of 285 pm and a 119Sn-NMR Shift δ = 3301 in Organome-tallic Derivatives of Sn(0)The reaction of Na[{Cp'(CO)2Mn}2H] with SnCl2, which produces the inidene compound [Cp'(CO)2Mn\documentclass{article}\usepackage{amsmath}\pagestyle{empty}\begin{document}$ {\rm C}\ddot - {\rm C} $\end{document}Sn(Cl)\documentclass{article}\usepackage{amsmath}\pagestyle{empty}\begin{document}$ {\rm C}\ddot - {\rm C} $\end{document}Mn-(CO)2Cp']- under standard workup procedures, results in the formation of [{Cp'(CO)2MnSn}2{μ2-Mn(CO)2Cp'}2{μ2-Cl}]- (1) when quenched with unpolar solvents. While, formally, 1 contains tin in its oxidation state zero, it may be conceived as composed of an Sn2-2 entity, which is linearly end-on coordinated to two Cp'(CO)2Mn 16-electron species; in addition the tin centers are bridged by two μ2-Mn(CO)2Cp' moieties and a μ2-Cl function. The resulting connectivity Sn2{μ2-Mn(CO)2Cp'}2{μ2-Cl} thus corresponds to a [1.1.1]propellane scaffolding. While there is no obvious need for a tin-tin bond in this propellane-type cage, a short Sn-Sn contact of only 285 pm is observed. While the 119Sn-NMR signal of 1 could not be recorded, the peculiar bonding in this type of compounds is generally mirrored in their unconventional 119Sn-NMR shift whereever signals can be observed: it is found that [{Cp*(CO)2Mn}3(μ3-Sn)], which contains trigonally planar-coordinated μ3-Sn as a naked ligand atom, has its 119Sn-NMR resonance at δ = 3301 well beyond the known range of 119Sn-NMR shifts. This finding is interpreted in terms of a relatively week Snpπ-Mndπ π bonding which leads to low-energy unoccupied molecular orbitals as the prerequisit for a large paramagnetic contribution to the NMR shift.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280217
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Pn-Liganden mit maximaler Elektronendonorfähigkeit, 7. Dreikomponentenreaktion von P4-Phosphor mit [CpxRh(CO)2] in Gegenwart von [Cr(CO)5THF] oder [CpMn(CO)2THF]. - Eine Methode zum Studium des Transformationsweges vom P4-Tetraeder zum planaren cyclo-P4-LigandenHerrn Professor Gerhard Fritz zum 75. Geburtstag gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 251-257 
    Details
    ISSN: 0009-2940
    Keywords: Tetraphosphorus ligands ; Bond cleavage in P4, stepwise ; Rhodium P4 complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pn Ligands with Maximum Electron-Donor Capacity, 7. - Three-Component Reaction of P4-Phosphorus with [CpxRh(CO)2] in the Presence of [Cr(CO)5THF] or [CpMn(CO)2THF]. - A Method of Studying the Pathway from Tetrahedral P4 to the Planar cyclo-P4 LigandHerrn Professor Gerhard Fritz zum 75. Geburtstag gewidmet.The reaction of P4 with [CpxRh(CO)2] (Cpx = Cp′, Cp′′; Cp′ = η5-C5H4tBu, Cp′′ = η5-C5H3tBu2-1,3) in the presence of [Cr(CO)5THF] leads to [CpxRh(CO)(η1:1-P4){Cr(CO)5}4] (1a, b), [Cp′′Rh(η4-P4){Cr(CO)5}3] (2b), and [Cp′Rh(η4-P4){Cr-(CO)5}4] (3a). In the corresponding reaction with [CpMn-(CO)2THF] no P4 takes part, and [(Cp′′RhCO)(CpMnCO)(μ-CO)2] (4) is formed. An X-ray structure determination of [CpxRh(CO)(η1:1-P4){Cr(CO)5}4] (1) and [Cp′Rh(η4-P4)-{Cr(CO)5}4] (3a) indicates a stepwise (PP) bond cleavage as the transformation pathway from the P4 tetrahedron to the cyclo-P4 ligand by passing a bicyclotetraphosphane. In the cyclo-P4 ligand complex 3a all P atoms are able to coordinate to [Cr(CO)5] groups. However, in [Cp′′Rh(η4-P4){Cr(CO)5}3] (2b) the additional tBu group at the Cpx ligand sterically influences the coordination behavior of the P atoms, and only three of them are able to coordinate to [Cr(CO)5] units. In these syntheses the [Cr(CO)5] moieties promote the reaction and stabilise intermediates along the reaction pathway. Variable-temperature 31P{1H}-NMR measurements indicate for 2b the freezing of the Cp′′ rotation at low temperature and reveals a ΔG≠c (at the coalescence temperature) of 36 kJ mol-1. Surprisingly, in [(Cp′′RhCO)(CpMnCO)(μ-CO)2]-(Rh-Mn) (4) the Cpx ligands are cis-oriented whereas in [(Cp*RhCO)(CpMnCO)(μ-CO)2](Rh-Mn) a trans arrangement is observed. This indicates the unusual behavior of the Cp′′ ligand as a “rod” and not as an “enlarged disk” like Cp* in the crystal lattice of these compounds.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280308
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Wasserlösliche Phosphane, IV. Tertiäre Alkylphosphane mit Ammoniumgruppen in den Seitenketten - Amphiphile mit basischen P-Atomen (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 275-279 
    Details
    ISSN: 0009-2940
    Keywords: Aminoalkylphosphanes ; N-Quaternisation ; P-Alkylation ; Cationic tertiary phosphanes ; Amphiphiles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Water-Soluble Phosphanes, IV. - Tertiary Alkylphosphanes with Ammonium Groups in the Side Chains  -  Amphiphiles with Basic P-AtomsBy stepwise aminoalkylation of PH3 with Me2N—(CH2)2—Cl in the superbasic medium DMSO/KOH the secondary phosphane [Me2N—(CH2)2]2PH (2) is obtained in good yields. Metallation of 2 with n-BuLi and subsequent reaction with Me2N—(CH2)2]2Cl affords the basic tertiary phosphane [Me2N—(CH2)2]2]3P (3), which on protonation with Ph3P · HBr in CH2Cl2 gives {[HNMe2 - (CH2)2]3P}3+ 3 Br- (4a) with an extremely high solubility in water. By oxidation of 3 with H2O2 and N-quaternisation with Me3O+ BF-4 the cationic phosphane oxide {[Me3N—(CH2)2]3P=O}3+ 3 BF-4 (5a) is formed, which could, however, not be reduced with SiHCl3 or Si2Cl6/NEt3 to the corresponding tricationic phosphane. Tertiary cationic phosphanes of type [RMe2N—(CH2)2—P(Oct)2]+ X- (8a, 8b, R = Me, C8H17; X = Br, I) are accessible by free radical addition of 1-octene to 7b and 7d. Addition of formaldehyde to 7a gives the hydroxymethyl phosphane 10a. By methylation of [RMe2N—(CH2)2—PH2]+I- (7d and 7e, R = CnH2n+1, n = 8, 12) with Mel under controlled condition and subsequent deprotonation of the phosphonium salts 12b and 12c the cationic tertiary phosphanes 13a and 13b with long alkyl side chains may be obtained in good yields.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280311
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Fe(NCMe)2+3-Komplexe von chiralen Tripodliganden mit drei verschiedenen Donorgruppen: Dynamik und StrukturHerrn Prof. Dr. Herrmann Schildknecht gewidmet. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 293-301 
    Details
    ISSN: 0009-2940
    Keywords: Tripodal ligands, chiral ; Iron tris(acetonitrile) tripod complexes ; Chiral triphosphanes ; Conformational analysis ; Ligand exchange ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fe(NCMe)2+3 Complexes of Chiral Tripod Ligands Bearing three Different Donor Groups: Dynamics and StructureChiral tripod ligands [tripod = CH3C(CH2PR2)(CH2PR′2)(CH2-PR′′2), 1a-d] with three different donor groups react with Fe(NCMe)6(BF4)2 to yield the complexes tripodFe(NCMe)3(BF4)2 (2a-d). These complexes show an idealized octahedral coordination based on a facial coordination of the tripod ligand. The asymmetry of the chiral tripod ligands a-d induces a differentiation of the remaining coordination sites at iron. The structure and the dynamic behaviour of the compounds 2a, b is elucidated by X-ray structural analyses and 2D-NMR techniques.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280314
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Masthead (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280401
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    Synthesis and Application of Ring-Substituted Analogues of the [4-(η-Cyclopentadienylidene)-4,7,7-trimethyl-4,5,6,7-tetrahydro-η5-indenyl]-ZrCl2 Ansa-Metallocene System (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 357-364 
    Details
    ISSN: 0009-2940
    Keywords: Ansa-metallocene ; Ziegler catalyst, homogeneous ; Propene polymerization ; Fulvenes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reaction of the 2,5-hexanedione-derived bisfulvene 1 with R—Li reagents (R = phenyl or n-butyl) yields the ring-closed [4-(cyclopentadienylidene)-7-R-4,7-dimethyl-4,5,6,7-tetrahydroindenyl]dilithium reagents 3. Their reaction with MCl4 (M = Ti, Zr, Hf) gives the corresponding ansa-group-4-metallocene dichloride complexes 4, 6, or 7. In a similar way the [7-allyl-4-(η-cyclopentadienylidene)-4,7-dimethyl-4,5,6,7-tetrahydro-η5-indenyl]metal dihalides (M = Ti, Zr) (6d, 4d) are prepared. Two diastereomers are formed in most cases, some of which could be separated. The five representative examples cis- and trans-4c, trans-4d, cis-6c, and trans-7c of these complexes were characterized by X-ray diffraction. All these six-membered ring-annulated C1-bridged ansa-metallocene dichlorides exhibit extremely small D1—Zr—D2 angles (D1 and D2 denote the centroids of the cyclopentadienyl rings) of 116.5°, i.e., they are characterized by a very open bite of the bent metallocene wedge. The homogeneous Ziegler-type catalysts derived from these ansa-zirconocenes by activation with methylalumoxane have high activities and all produce low-molecular mass atactic polypropylenes or propene oligomers.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280407
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Ionenpaarbildung und Cyclisierungsreaktionen an koordinierten Oxalamidinen (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 405-412 
    Details
    ISSN: 0009-2940
    Keywords: Sodium oxalamidinates ; 2-Imidazolidinone ; Ionic molybdenum carbonyl complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ion Pairing and Cyclization on Coordinatively Bound OxalamidinesThe tetraphenyloxalamidine ligand of complex 8a reacts easily in the presence of bases with elementorganic dichlorides (R2MCl2) to form coordinated metalacycles. The cyclization with phosgene gives the (CO)4Mo-coordinated 1,3-diphenyl-4,5-bis(phenylimino)-2-imidazolidinones 10. In contrast to the reaction forming the piperazine derivative 2, the reaction of 8a with oxalyl chloride also proceeds to 10 by decarbonylation. The product of this cyclization, (CO)4Mo(OCTPOA) (10), and two possible intermediates, the dinuclear sodium salts Na2(THF)8[(CO)4Mo(HTPOA)]2 (11a) and Na(THF)4[(CO)4Mo(EtO2COCTTOA)]2 (15) have been characterized by X-ray analyses. 11a contains the coordinated oxalaminate anion. The structure of the ionic complex 15 shows the simultaneous attack at both sp3-hybridized nitrogen atoms and the selective formation of the five-membered 2-imidazolidinone heterocycle by coordination of the oxalamidine. Both sodium complexes 11a and 15 are dimeric and centrosymmetric ion pairs. Complex 11a contains two C≡O—Na—O≡C bridges while compound 15 has a central [Na2O2] four-membered ring consisting of sodium alcoholate bridges.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280412
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Syntheses of Cyclic and Acyclic Bis(perfluoroalkylthio)nitronium Salts (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 429-433 
    Details
    ISSN: 0009-2940
    Keywords: Nitronium ions ; One-electron oxidation ; Superacidic systems ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (F3CS)3N (1) is oxidized quantitatively by AsF5 to the first bis(perfluoroalkylthio)nitronium salt (F3CS)2N+AsF-6 (2). Addition of halide ions (F-, Cl-, Br-, l-) to the cation of 2 destroys the S—N—S chain. (F2CSCl)2 undergoes with ammonia a cyclization reaction to S—CF2—CF2—S—N—H (3), which can be derivatized with F3CSCl or (F2CSCl)2 to S—CF2—CF2—S—N—SCF3 (3a) and (S—CF2—CF2—S—N—SCF2—)2 (3b), respectively. Oxidation of 3a with AsF5 yields (S—CF2—CF2—S—N+AsF-6 (4) and byproducts, which suggest formation of a {3a}+• radical cation as an intermediate in this reaction. Pure 4 is accessible by reaction of 3 with AsF5 in 54% yield. The chemical and spectroscopic properties of the new species are discussed.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280416
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Masthead (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280501
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Structure and Conformation of Bis(trifluoromethylthio)methane, CH2(SCF3)2 (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 461-464 
    Details
    ISSN: 0009-2940
    Keywords: Bis(trifluoromethylthio)methane ; Gas-phase structure ; Conformational properties ; Electron diffraction ; Calculations, ab initio ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The geometric structure and conformational properties of bis(trifluoromethylthio)methane, CH2(SCF3)2' were determined by gas electron diffraction. The main conformer (70 ± 15%) possesses C2 symmetry with dihedral angles Φ(SCSC) = 79.1(10)°. The second conformer possesses C1 symmetry. The following skeletal geometric parameters (distances ra [pm] and angles 〈α[°] with 3-σ uncertainties) were obtained: C—S 183.6(3), S—CF3, 179.3(3), S—C—S 112.1(6), and C—S—C 98.2(10). The geometric structures and relative conformational stabilities were well reproduced by ab initio calculations at the HF/3-21G* level.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280505
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Pyridyl-Functionalised Cyclopentadienyl Ligands: Building Blocks for Oligonuclear Organometallic Assemblies (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 481-485 
    Details
    ISSN: 0009-2940
    Keywords: Cyclopentadienyl ligands, functionalised ; Hemilabile ligands ; Cyclopentadienes, pyridyl-functionalised ; Ferrocenes, pyridyl-functionalised ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lithiated 2-methylpyridine reacts with 2,3,4,5-tetramethylfulvene (TMF) to give 2-[2-(2,3,4,5-tetramethylcyclopenta-1,4-dien-1-yl)ethyl]pyridine (2H) after aqueous work-up. Similarly, a mixture of 2-methyl-6-[2-(2,3,4,5-tetramethylcyclopenta-1,4-dien-1-yl)ethyl]pyridine (3H) and 2,6-bis[2-(2,3,4,5-tetramethylcyclopenta-1,4-dien-1-yl)ethyl]pyridine (4H2) was obtained from monolithiated 2,6-dimethylpyridine and TMF. All three compounds were obtained as a roughly statistical mixture of double-bond isomers. 2-Lithiopyridine reacts with 2,3,4,5-tetramethylcyclopent-2-enone to yield 2-(2,3,4,5-tetramethylcyclopenta-1,3-dien-1-yl)pyridine (5H) after acidic work-up. This compound was obtained as a non-statistical mixture of double-bond isomers, which is presumably due to intramolecular hydrogen-bond interactions. The lithiated derivatives 2Li, 3Li and 5Li react with iron(II) chloride to afford the respective ferrocenes (2)2Fe (8), (3)2Fe (9) and (5)2Fe (10). The structure of 10 was determined by a single-crystal X-ray diffraction study. The cyclopentadienyl ligands adopt a staggered conformation; the pyridyl rings are arranged in a stacked fashion with the closest ring-ring contact being 3.16 Å. The distance between the iron atom and the cyclopentadienyl ring centroids is 1.66 Å.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280508
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Tin for Organic Synthesis, 12. Synthesis of Aromatic and Olefinic Sodium Sulfonates by Electrophilic Destannylation with Trimethylsilyl Chlorosulfonate (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 575-580 
    Details
    ISSN: 0009-2940
    Keywords: Electrophilic aromatic substitution ; Electrophilic vinylic substitution ; Trialkylstannanes, application of ; Arylsulfonates, sodium salts of ; Vinylsulfonates, sodium salts of ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A mild and effective method for the preparation of a variety of aromatic, olefinic, and acetylenic sodium sulfonates is described. The reaction of trialkylaryl- (2a-k) and -heteroarylstannanes (4a-d), bis-(1-alkenyl)dibutylstannanes (6a-f), or trialkylalkynylsta manes with trimethylsilyl chlorosulfonate (1) followed by hydrolysis with aqueous NaHCO3 provides the sodium sulfonates in an ipso-specific and in the case of vinylic stannanes stereospecific manner. A comparison of the reactivity of stannylated and silylated olefinic compounds 13 and 14 underlines the greater leaving ability of the stannyl moiety. The in situ preparation of the stannanes makes it possible to apply the synthetic method to natural products such as N-substituted apocodeine (17).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280609
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    On the Regioselectivity and Stereoselectivity of the Carbene Transfer from Fischer Carbene Complexes to Trisubstituted Electron-Deficient 1,3-DienesDedicated to Professor Rolf Huisgen on the occasion of his 75th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 605-614 
    Details
    ISSN: 0009-2940
    Keywords: Chromium complexes ; Carbene complexes ; 1,3-Dienes, electron-deficient ; [2 + 1] Cycloadditions ; Vinylcyclopropanes, donor-acceptor-substituted ; Diastereoselectivity ; Regioselectivity ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermal reactions of Fischer carbene complex 1 with trisubstituted electron-deficient 1,3-dienes 7, 8, 23, 25, 32, and 35 provided highly substituted vinylcyclopropanes in good yields. The carbene transfer proceeds highly regioselectively favouring cyclopropanation of the double bond not bearing the ester function. In addition, the diastereoselectivity is generally fairly high in preference of cyclopropanes with the methoxy group cis-positioned with respect to the olefin moiety. The reaction of methylcarbene complex 2 with diene ester 8 displays inversed regioselectivity. These observations are discussed together with solvent effects, and a mechanistic rationale is presented.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280613
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Synthesis and Characterization of Copper, Nickel and Cobalt Complexes of N,N′-Dimethyl-2,11-diaza[3,3](2,6)pyridinophane (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 531-539 
    Details
    ISSN: 0009-2940
    Keywords: 2,11-Diaza[3,3](2,6)pyridinophane ; N,N′-dimethyl- ; Tetraazamacrocyclic complexes ; cis-Octahedral coordination geometry ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The properties of the tetraazamacrocyclic compound N,N′-dimethyl-2,11-diaza[3,3](2,6)pyridinophane (L-N4Me2) as a ligand for some selected metal chlorides have been examined. The crystal structure of the uncoordinated ligand reveals a syn chair-chair conformation. In solution, the ligand displays fluctional behavior. Reaction of L-N4Me2 with the chlorides of copper(II), nickel(II), and cobalt(II) affords the complexes [Cu(L-N4Me2)Cl2] · H2O (3), [Ni(L-N4Me2)(H2O)Cl]Cl · H2O (4), and [Co(L-N4Me2)Cl2] · 2 H2O (5) in which the ligand adopts a syn boat-boat conformation. The crystal structures of 4 and 5 are presented. Due to the small cavity of the 12-membered ring of the ligand, exclusively distorted cis-octahedral coordination geometries are found at the metal sites. A comparison of structural data of several complexes with this ligand shows that the extent of the distortions from ideal octahedral geometry is mainly determined by the M-Npy bond strength. The electronic as well as the solution properties of the described complexes have been investigated by electronic absorption spectroscopy. ESR spectroscopy, and electrochemical methods.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280602
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...