ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
The 13C N. M. R. Spectra of Some Ylides of Phosphorus and Arsenic and of Their Silyl DerivativesThe 13C n.m.r. spectra of the phosphorus and arsenic ylides (CH3)3P=CH2, (C2H5)3P=CH2, (C2H5)3P=CHCH3, (CH3)3As=CH2, (CH3)3P=CHSi(CH3)3, (CH3)3P=C[Si(CH3)3]2, (CH3)3As=CHSi(CH3)3 and (CH3)3As=C[Si(CH3)3]2 are discussed. On the basis of the coupling constants a nonplanar geometry of the ylidic carbanion in the arsenic ylide (CH3)3As=CH2 is predicted. Introduction of silyl substituents, however, probably causes flattening of this pyramidal structure. The planar arrangement is generally typical for the carbanions of phosphorus ylides.
Notes:
Die 13C-NMR-Spektren der Phosphor- und Arsen-ylide (CH3)3P=CH2, (C2H5)3P=CH2, (C2H5)3P=CHCH3, (CH3)3As=CH2, (CH3)3P=CHSi(CH3)3, (CH3)3P=C[Si(CH3)3]2, (CH3)3As=CHSi(CH3)3 und (CH3)3As=C[Si(CH3)3]2 werden diskutiert und für (CH3)3As=CH2 auf der Basis der Kopplungskonstanten eine nicht-planare Geometrie des ylidischen Carbanions vorhergesagt. Die Einführung von Silylgruppen bewirkt jedoch vermutlich eine Einebnung dieser Struktur, wie es für Phosphor-ylide generell typisch ist.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19751080820
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