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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 589 (1990), S. 187-198 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,3,4-Oxadiphospholanes and 1,3,4-Thiadiphospholanes from Diphosphorus-substituted 2-Oxa- and 2-Thia-propanesThe synthesis of phosphonates and phosphinates of the type (RO)2(O)PCH2ZCH2P(O)(OR)2, R1(RO)(O)PCH2ZCH2P(O)(OR)2 and R1(RO)(O)PCH2ZCH2P(O)(OR)R1 (with Z = O, S; R = Et, Pri; R1 = Me, Ph) is reported. Acyclic diphosphanes, R1(H)PCH2ZCH2P(H)R2 (with Z = O, S; R1 = R2 = H, Me, Ph; R1 = H, R2 = Me), and 1,3,4-Oxadiphospholanes as well as 1,3,4-Thiadiphospholanes are obtained from the esters by reduction.
    Notes: Die Darstellung von Phosphonaten und Phosphinaten der Zusammensetzung (RO)2(O)PCH2ZCH2P(O)(OR)2, R1(RO)(O)PCH2ZCH2P(O)(OR)2, und R1(RO)(O)PCH2ZCH2P(O)(OR)R1 (mit Z = O, S; R = Et, Pri; R1 = Me, Ph) wird beschrieben. Durch Reduktion der Ester sind die acyclischen Diphosphane, R1(H)PCH2ZCH2P(H)R2 (mit Z = O, S; R1 = R2 = H, Me, Ph; R1 = H, R2 = Me) und 1,3,4-Oxadiphospholane bzw. 1,3,4-Thiadiphospholane zugänglich.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0009-2940
    Keywords: Heterodinuclear cyclooctatetraene complexes ; Paramagnetism ; ESR of electron spin doublet and of electron spin quartet ; Redox properties ; d-d Interactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cooperative Effects in π1-Ligand-Bridged Dinuclear Complexes, XIII[1]. - Unexpected Weak d-d Interactions in Synfacial Heterodinuclear μ1-Cyclooctatetraene Complexes of the Type {(CpCr)[(CO)3M′]}μ1-Cot (M′=Fe, Cr, W)The heterodinuclear complexes {(CpCr)[(CO)3M′]}μ1-Cot (Cot=C8H8; M′=Fe, Cr, W) (5 - 7) and {(Cp*Cr)[(CO)3Cr]}μ1-Cot (Cp*=C5Me5) (9) are synthesized by the reaction of the corresponding mononuclear Cot complexes CpCr(η61-Cot) (4) and Cp*Cr(η61-Cot) (8), respectively, with M′(CO)3(EtCN)3 (M′=Cr, W) and with Fe2(CO)9. The CrFe compound 5 is obtained in very low yield only. However, much better yields of 5 are achieved in the reaction of CrCl2 and CrCp2 with (CO)3Fe(η41-Cot) (10) in the presence of an excess of Zn. X-ray structure determinations of 5 and 6 reveal synfacial configurations of the CpCr and M′(CO)3 units with a μ1-η5:3- and μ1-η4:51-Cot bonding mode for 5 and 6, respectively. The metal - metal distances are 2.9369(13) Å for 5 and 2.81(2) Å for 6 indicating metal - metal single bonds. 5 contains 33 valence electrons (ve) and is paramagnetic with one unpaired electron. A well-resolved fluid-solution ESR spectrum of 5 shows a 53Cr and 1H hyperfine structure (hfs). The 1H hfs can be calculated with three different 1H hyperfine coupling constants (1H hfcc) indicative of protons in α1-position with respect to the paramagnetic metal center: one 1H hfcc of the five Cp protons (1.68 G), one of three (3.32 G) and one of two protons of the Cot ligand (5.04 G). This agrees with the Cot bonding mode of the CpCr unit in the crystalline phase. The ratio of 3:2 protons for the Cot ligand prove the rigidity of the Cot ligand on the ESR time scale. The excellent agreement of the ESR data of the liquid and frozen solution ESR spectra of 5 with the ESR data of the mononuclear complex CpCr(η61-Cot) leads to the conclusion that the unpaired electron in 5 must predominantly be chromium-centered. 6, 7, and 9 have 31 ve and are paramagnetic with three unpaired electrons as shown by means of ESR spectroscopy and magnetic measurements. The calculations of the quartet ESR spectra of 6, 7, and 9 reveal zero-field splitting parameters D ranging from 3.6 to 4.8 cm-1 which are similar to that of the mononuclear quartet compound vanadocene. The small range in the parameters D prove the minor influence of the second metal on going from Cr to W. Hence, the three unpaired electrons are assumed to be mainly localized on the Cr center of the CpCr unit. Cyclic voltammetry studies result in the redoxcascade - 2 ⇄ - 1 ⇄ 0 ⇄ + 1 for 5 and 7 at +20°C and for 6 at -35°C. However, at +20°C 6 and 9 only show one electrochemically reversible reduction wave 0/-1, whereas the oxidation 0/+1 and the second reduction -1/-2 are irreversible. The redox potentials indicate a considerable influence of the metal combinations. On the strength of the ESR spectroscopic results and according to the results of crystal structure determinations, an isolobal relationship is drawn between the (CO)3M′(η8 - ×1-Cot) fragment and a cyclic organic π1-ligand with the hapticity × + 1.
    Additional Material: 7 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 2641-2641 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A New Highly Efficient Method for the Synthesis of 1'-Alkyl- and 1'-Phenyl-Substituted Pyrimidine Acyclonucleosides
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 55-59 
    ISSN: 0009-2940
    Keywords: Gallium-transition metal complexes ; Iron complexes ; Manganese complexes ; Molybdenum complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The transition metal-gallium complexes [Ga(MLn)3] [where MLn=Fe(CO)2(η-C5H5), Mo(CO)3(η-C5H5), Co(CO)3(PPh3), and Mn(CO)5] have been synthesised by salt elimination between GaCl3 and MI(MLn) (MI=Na/K). The iron complex [Ga{Fe(CO)2(η-C5H5)}3] (1) has been characterised by X-ray crystallography and shown to contain a planar, three-coordinate gallium centre bound to three Fe(CO)2(η-C5H5) fragments by unsupported Ga-Fe bonds [av. 2.444(1) Å]. A partial structure determination of [Ga{Mo(CO)3(η-C5H5)}3] (5) is consistent with a trigonal-planar GaMo3 core. Brief mention is also made of two chloro complexes [GaCl(MLn)2] [MLn=Fe(CO)2(η-C5-H5) and Co(CO)3(PPh3)].
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 1619-1619 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 53 (1907), S. 349-360 
    ISSN: 0863-1778
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Der scheinbar zu hohe Antimongehalt, der sich bei der Elektrolyse von Antimonsulfosalzen ergibt, steigt, wie bereits von Henz festgestellt wurde, mit der Stromstärke und der Antinionmenge, die sich in der Lösung befindet.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 202. Hepta-tert-butylnonaphosphane(7), P9(t-Bu)7, and Octa-tert-butyldecaphosphane(8), P10(t-Bu)8  - Preparation and Structure Determination by 31P-NMR SpectroscopyHepta-tert-butylnonaphosphane(7) (1) and octa-tert-butyldecaphosphane(8) (2), the first bicyclophosphanes PnRn-2 with n 〉 8, have been obtained by dehalogenating t-BuPCl2 with magnesium in the presence of P4 and have been isolated in pure form. According to 31P-NMR spectroscopic investigations, 1 and 2 are structurally homologues of P8(t-Bu)6 [8], in which two tert-butylsubstituted P4 rings are linked through a α-bond. The compounds 1 and 2 differ from P8(t-Bu)6 by the insertion of a (t-Bu)-group and a [-P(t-Bu)-]2 chain, consisting of two (t-Bu)-groups, respectively, between the two (t-BuP)3P rings. Hence, 1, is bis(2,3,4-tri-tert-butylcyclotetraphosphanyl)-tert-butylphosphane and 2 is 1,2-bis(2,3,4-tri-tert-butylcyclotetraphosphanyl)-1,2-di-tert-butyldiphosphane which exists in the meso-configuration due to steric reasons.
    Notes: Hepta-tert-butyl-nonaphosphan(7) (1), und Octa-tert-butyl-decaphosphan(8) (2) wurden durch Enthalogenierung von t-BuPCl2 mit Magnesium in Gegenwart von P4 als erste Bicyclophosphane PnRn-2 mit n 〉 8 gewonnen und analysenrein isoliert. Nach kernresonanz-spektroskopischen Untersuchungen sind 1 und 2 strukturell Homologe von P8(t-Bu)6 [8], in dem zwei tert-butylsubstituierte P4-Ringe über eine α-Bindung miteinander verknüpft sind. Die Verbindungen 1 und 2 unterscheiden sich von P8(t-Bu)--6 durch die Einschiebung einer (t-Bu)-Gruppe bzw. einer aus zwei (t-Bu)-Gruppen bestehenden [-P(t-Bu)-]2-Kette zwischen die beiden (t-buP)3P-Ringe. Demnach handelt es sich bei 1, um Bis (2,3,4-tri-tert-butylcyclotetraphosphanyl)-tert-butylphosphan, bei 2 um 1,2-Bis(2,3,4-tri-tert-butycyclotetraphosphanyl)-1,2-di-tert-butylphosphan, bei 2 um 1,2-Bis(2,3,4-tri-tert-butylcyclotetraphosphanyl)-1,2-di-tert-butyldiphosphan, das aus sterischen Gründen in der meso-Form vorliegt.
    Additional Material: 3 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 585 (1990), S. 18-26 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 205. Nona-tert-butyltridecaphosphane(9), P13(t-Bu)9  -  Structural Principles of Bi- and Tricyclic tert-ButylphosphanesNona-tert-butyltridecaphosphane(9) (1) has been obtained by dehalogenating tert-butyldichlorophosphane with magnesium in the presence of white phosphorus and has been isolated in pure form. According to NMR spectroscopic investigations 1 has a conjuncto-phosphane skeleton consisting of three P4 rings which are linked through α bonds either directly or via an exocyclic phosphino group. Hence, compound 1 is 3-[tert-butyl(2, 3, 4-tri-tert-butylcyclotetraphosphanyl)-phosphino]-2,2′,3′,4,4′-penta-tert-butyl-1, 1′-bicycloteraphosphane. Contrary to the skeletal structures of sterically unperturbed, polycyclic phosphanes the structures of bi- and tricyclic tert-butylphosphanes are decisively determined by the steric interactions of the tert-butyl substituents besides the synthetic route.
    Notes: Nona-tert-butyl-tridecaphosphan(9) (1) wurde durch Enthalogenierung von tert-Butyldichlorphosphan mit Magnesium in Gegenwart von weißem Phosphor neben anderen tert-Butylphosphanen erhalten und analysenrein isoliert. Nach kernresonanzspektroskopischen Untersuchungen weist 1 ein Konjunkto-Phosphangerüst aus drei P4-Ringen auf, die über α-Bindungen  -  entweder direkt oder über eine exocyclische Phosphinogruppe  -  miteinander verknüpft sind. Demnach handelt es sich bei Verbindung 1 um 3-[tert-Butyl(2,3,4-tri-tert- butylcyclotetraphosphanyl)-phosphino]-2,2′,3′,4,4′-penta-tert-butyl-1,1′-bicyclotetraphosphan. Die Gerüststrukturen bi-und tricyclischer tert-Butylphosphane werden im Unterschied zu denen sterisch ungestörter polycyclischer Phosphane neben dem Syntheseweg vor allem durch die sterischen Wechselwirkungen der tert-Butylsubstituenten bestimmt.
    Additional Material: 2 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 582 (1990), S. 217-223 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Phasendiagramm des Systems Pr2S3—Pr2O3—Ga2S3Durch DTA, Hochtemperatur DTA, Röntgendiffraktion und Mikrostrukturanalysen sind die Phasengleichgewichte im ternären System Pr2S3—Pr2O3—Ga2S3 untersucht worden. Die Liquidus-Kurve wird dargestellt. Die Bereiche der ersten Kristallisation von Phasen und die Glasbildung sowie die Koordinaten von allen nicht- und monovarianten Gleichgewichten wurden bestimmt.
    Notes: By the methods of differential thermal, high-temperature differential thermal, visual polythermal, X-ray diffraction and microstructural analyses phase equilibria in the ternary system Pr2S3—Pr2O3—Ga2S3 have been investigated. The projection of liquidus surface was plotted. The regions of primary crystallization of phases and glass formation as well as coordinates of all non- and mono-variant equilibria were established.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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