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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 156 (1988), S. 21-27 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Es wurden Polyester basierend auf 1,4,5,6,7,7-Hexachlor-5-norbornen-2,3-dicarbonällureanhydrid (I), Tetrachlorphthalsäureanhydrid (II), Dibromneopentylglykol (II), ein Polyesterblend (V) bestehend aus dem Polyester (III) und einem Polyester (IV) für allgemeine Zwecke, ein Polyester (VI) basierend auf 1,4,5,6,7,7-Hexachlor-5-norbornen-2,3-dicarbonsäureanhydrid und dem Polyester III und ein Polyesterblend (VII) bestehend aus den Polyestern I und III hergestellt. Ihre chemische Resistenz und ihre Feuchtigkeitsaufnahme bei Temperaturen von 25 und 65°C wurden in Säuren, 20% NaOH und Wasser untersucht. Hierbei wurde gefunden, daß der Polyester (III) von den Säuren am wenigsten angegriffen wird. Verglichen mit unbehandelten Poly meren fand bei beiden Temperaturen in 20% NaOH eine Gewichtsabnahme bei allen Polyestern statt, mit Ausnahme des Polyesters VII. Erne Gewichtszunahme aller Polyester wurde beobachtet durch Feuchtigkeitsaufnahme sowohl bei 25 als auch bei 65°C, wobei die Zunahme bei der höheren Temperatur größer war. Der Polyester III zeigte die geringste Feuchtigkeitsaufnahme.
    Notes: Chlorendic anhydride based polyester (I,) tetrachlorophthalic anhydride based polyester (II), dibromoneopentyl glycol based polyester (III,) general purpose polyester (IV,) blend of dibromoneopentyl glycol based polyester with general purpose polyester (V,) chlorendic anhydride and dibromoneopentyl glycol based polyester (VI), and a blend of chlorendic anhydride based polyester and dibromoneopentyl glycol based polyester (VII) were prepared and their chemical resistance and moisture absorption studied in various reagents, acid, alkali, and water, at 25 and 65°C. It is found that the polyester (III) is the least affected in the presence of the acids. In 20% NaOH, there was a decrease in weight for all polyesters at both the temperatures compared to the control except the polyester (VII). Increase in weight of all the polyesters was observed during the absorption of moisture both at 25 and 65°C. The increase was higher at higher temperature. Polyester (III) thus shows the least absorption of moisture.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 2067-2069 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4-Benzylidene-5-oxazolones 5 do not react with P(OMe)3; with P(NMe2)3 they give rise to 4-α-[bis(dimethylamino)phosphoryl]benzyl-5-dimethylaminooxazoles 6. This behavior differs from that of the corresponding pyrazolones and isoxazolones and is attributed to a decreased stability of the dipolar adduct resulting from a β attack of phosphorus.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 475-480 
    ISSN: 0009-2940
    Keywords: 1,3-Azaphosphole, annulation to pyridine ; 2-Phosphaindolizines ; Pyridinium bromides, 1,2-dialkyl ; Phosphorus(III) chloride, condensation with CH2 groups ; Calculations, MNDO ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 4
    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
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 2367-2371 
    ISSN: 0009-2940
    Keywords: Tin, (alkylthio)stilbene complexes of ; cis-stilbene-α-thiol, β-(methylthio)-, tin(IV) complexes of ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The S-methyl-cis-stilbene-α,β-dithiolate of Sn(IV), Sn[Ph(S)C=C(SCH3)Ph]4, has an octacoordinate structure with two sets of four covalent and coordinate Sn-S and Sn-S(CH3) bonds of 2.425(3) and 3.599(3) Å, respectively. Both types of Sn-S bonds are close to being tetrahedral, the coordination geometry is a distorted cube. This unprecedented structure appears to involve conventional covalent and outer-sphere coordinative Sn-S bonds. In the diphenyl derivative Ph2Sn[Ph(S)C=C(SCH3)Ph]2 the SnC2S2 core formed by the covalent Sn-C and Sn-S(thiolato) bonds is tetrahedral, but two coordinate outer-sphere Sn-S(CH3) bonds of 3.500(3) Å are also present. In the related SnCl2[Ph(S)C=C(SCH3)Ph]2 the presence of the polar Sn-Cl bonds prevents outer-sphere bonding; the coordination geometry is distorted octahedral. In the triphenyltin derivative Ph3Sn[Ph(S)C=C(SCH3)Ph] the coordination geometry is tetrahedral, the thiol-thioether ligand being monodentate with the SCH3 group in a non-interactive position.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 123 (1967), S. 43-61 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Silver stained Cordylophora were examined by light and electron microscopy, which provided a general picture of nerve cell forms and distribution for comparison with electron micrographs of osmium-fixed tissues from the same hydroid. Muscle, nerve and neurosensory components were studied in the nectophore of Nanomia (O. Siphonophora) and in the hydromedusae Sarsia and Euphysa by means of vital staining and optical and electron microscopy of epon sections; particular attention was given to relationships and interconnections between the cellular elements of the two marginal nerve rings. Mitochondrial size, numbers and types of vesicles and the occurrence of neurotubules and of parts of sensory cilia may provide useful ultrastructural clues for recognizing nerve elements, but serial sections are often needed to make identification conclusive.In Cordylophora and Nanomia, some neurites contain massed A vesicles (membrane-bounded dense granules) suggestive of neurosecretion (cf. reports on Hydra). However, a small type of A vesicle also occurs at synapses in Sarsia, indicating a probable role here in junctional transmission. Vesicles occur on both sides of some synapses (as previously reported for Cyanea) but on one side only in others, these being the first examples of polarized junctional ultrastructure in coelenterates.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1434-1948
    Keywords: Phosphorus heterocycles ; P ligands ; Transition metals ; Carbonyl complexes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The complex chemical behaviour of 2-phosphaindolizines 1 (1,3-azaphospholo[1,5-a]pyridines) towards metal carbonyl compounds was studied. (η1-2-Phosphaindolizine)M(CO)5 complexes 2-4 (M = Cr, Mo, W) were formed from 1 and [(THF)M(CO)5], the cis-L2Cr(CO)4 complex 5f from 1f and tetracarbonyl(norbornadiene) chromium(0). The reaction of 2-phosphaindolizines 1e, 1f, or 1g with tricarbonyl(cycloheptatriene)molybdenum(0) or tricarbonyl(mesitylene)tungsten(0) yielded σ-complexes of the types L2M(CO)4or L3M(CO)3 rather than isolable π-complexes. In one case a strong upfield signal (δ31P = 6.1) was observed with a coordination shift of Δδ = -161.7, which is typical for π-coordination. Prolonged reaction or work-up led, however, to dismutation yielding 1g and the fac-L3Mo(CO)3 complex 6g. X-ray structure analysis of 2a indicates an increased 10π-delocalization compared with 1a and a changed conformation of the acyl substituent. The influence of substituents and metals on the 31P and 13C complexation chemical shifts and coupling constants is discussed.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1434-193X
    Keywords: Oxo enamines ; Reductive addition ; Hydrazoic acid ; δ-Lactones ; δ-Lactams ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: -γ-Oxo-α,β-unsaturated δ-lactones and lactams, which are easily accessible from their corresponding 2-furylcarbinols, were used as substrates for the 1,4-reductive addition of hydrazoic acid. The outcome of the reaction is the formation, in high yields, of the corresponding α-amino-γ-oxo-α,β-unsaturated δ-lactones and -lactams, compounds of great biological and synthetic interest.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Heteroatom Chemistry 3 (1992), S. 359-366 
    ISSN: 1042-7163
    Keywords: Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bromine does not add to phosphorus in a 2-phosphaindolizine 1 but substitutes its 1-position. The 1-bromo derivatives 2 are best prepared with Br2/NEt3 or N-bromosuccinimide. Their hydrolysis is remarkable; it involves a debromination of C-1, an oxidation of P and a selective opening of the P/C-3 bond.PCl3 also causes a substitution of the 1-position. The resulting 1-dichlorophosphino derivatives 5 easily undergo a substituent exchange at the exocyclic phosphorus. More 1-phosphino derivatives are formed in the reaction of 1 with phenyl and diazaphospholyl dichlorophosphine.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Heteroatom Chemistry 9 (1998), S. 333-339 
    ISSN: 1042-7163
    Keywords: Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Eight new 2-phosphaindolizines 2 have been obtained by [4 + 1] cyclocondensation of 1,2-dialkylpyridinium halides 1 with PCl3. The X-ray structure analysis of 2a is consistent with the integration of the 1,3-azaphosphole ring in the 10π-aromatic system. The charge densities on phosphorus of various representatives as obtained by PM3 calculations correlate approximately with the 31P-NMR shifts. The mass spectral fragmentation of 2a resembles that of its nonphosphorus analog. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:333-339, 1998
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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