NMR SPECTROSCOPIC AND COMPUTATIONAL INVESTIGATIONS OF SIGMA-INTERACTIONS IN CARBOCATIONS - THE BETA-SILYL EFFECT IN VINYL CATIONS

被引：23

作者：

SIEHL, HU

机构：

[1] Institute of Organic Chemistry, University of Tubingen

来源：

PURE AND APPLIED CHEMISTRY | 1995年 / 67卷 / 05期

基金：

日本学术振兴会;

关键词：

D O I：

10.1351/pac199567050769

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The para carbon chemical shift in 1-mesityl substituted vinyl cations and the torsional barrier for the methoxy group rotation in 1-p(anisyl)vinyl cations are used to evaluate the magnitude of the silyl effect. The hyperconjugative stabilization by beta-silicon groups and the accompanying geometrical distortions are studied experimentally and computationally in dienyl-cations and 1-cyclopropylvinyl cations. A geminal methyl substituent enhances the interaction of a beta-silyl group with the vacant p-orbital.

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页码：769 / 775

页数：7

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