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  • Wiley-Blackwell  (2)
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  • 1
    Electronic Resource
    Electronic Resource
    Doppelylide, I. Synthese und Eigenschaften von Hexamethyl- und sym-Tetramethyldiphenylcarbodiphosphoran (1977)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 3501-3507 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Double Ylides, I Synthesis and Some Properties of Hexamethyl- and sym-TetramethyldiphenylcarbodiphosphoraneHexamethylcarbodiphosphorane, (CH3)3P=C=P(CH3)3 (1), can be prepared by heating of a mixture of (CH3)3P=CHP(CH3)3F (2a) with NaH, or from 2a with n-BuLi. 2a is obtained by the reaction of (CH3)3PF2 with the ylides (CH3)3P=CH2 or (CH3)3P=CHSi(CH3)3 with elimination of [(CH3)4P]F or (CH3)3SiF, resp. The reaction of the chlorides [(CH3)3PCHP(CH3)3]C1 (2b) and [(CH3)3PCH2P(CH3)3]C12 (3b) with n-BuLi yields also 1. Spectroscopic data indicate a high carbanionic character for the central carbon in 1. No non-cumulated isomers (1a, b) have been detected. With (CH3)3SiC1, a side-chain derivative (CH3)3P=CH—P(CH3)2=CHSi(CH3)3 (4) is formed in a transylidation reaction. C6H5(CH3)2P=C=P(CH3)2C6H5 (6) was prepared from the corresponding dibromide 5 with NaNH2 in THF. Contrary to compound 1, this yellow double ylide is a labile compound.
    Notes: Hexamethylcarbodiphosphoran, (CH3)3P=C=P(CH3)3 (1), ist durch trockene Destillation der Mischung von (CH3)3P=CHP(CH3)3F (2a) mit NaH oder aus 2a und n-Butyllithium darstellbar. 2a entsteht aus (CH3)3PF2 mit den Yliden (CH3)3P=CH2 oder (CH3)3P=CH—Si(CH3)3 unter Abspaltung von [(CH3)4P]F bzw. (CH3)3SiF. Auch [(CH3)3PCHP(CH3)3]C1 (2b) und [(CH3)3PCH2P(CH3)3]C12 (3b) ergeben mit n-BuLi die Verbindung 1. Nach spektroskopischen Daten besitzt 1 eine hohen Carbanioncharakter am zentralen C-Atom. Nichtkumulierte Isomere 1a, b wurden nicht gefunden. Mit (CH3)3SiCi entsteht unter Umylidierung das Seitenkettenderivat (CH3)3P=CH—P(CH3)2=CHSi(CH3)3 (4). - C6H5(CH3)2P=C=P(CH3)2C6H5 (6) wurde aus dem korrespondierenden Dibromid 5 mit NaNH2 im THF dargestellt. Das gelbe Doppelylid ist im Gegensatz zu 1 leicht zersetzlich.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19771101105
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  • 2
    Electronic Resource
    Electronic Resource
    Conformational and solid-state studies of diphenyl 1-hydroxy-1-phenylethylphosphonate (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Heteroatom Chemistry 7 (1996), S. 9-16 
    Details
    ISSN: 1042-7163
    Keywords: Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The crystal structure of the title compound, diphenyl 1-hydroxy-1-phenylethylphosphonate (1), was determined by the single-crystal X-ray diffraction method. The crystallographic data for 1 are as follow: C20H19O4P, Mr = 354.34, monoclinic, P21/n, a = 9.787(1) Å, b = 20.235(1) Å, c = 9.797(1) Å, β = 106.18(3)°, V = 1863.3(4) Å3, Z = 4, Dcalc = 1.26 g/cm3, λ(Mo-Ka) = 0.71073 Å, μ = 1.6 cm-1, F(000) = 744, R = 0.018, and Rw = 0.032 for 2258 observed reflections. The solid-state structure in a dimeric packing mode exhibits intermolecular hydrogen bonding of the type P = O···H-O. Infrared solution studies (CCl4) indicate that upon high dilution (10-4 M) the dimers completely dissociate to give conformers with and without intramolecular hydrogen bonds. Theoretical studies (PM3) were undertaken to determine the energy profile about the P-C torsional angle, which exhibited low energy barriers to rotation with no clear minimum energy conformation. © 1996 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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