Asymmetric conjugate addition to α-halo enones:: Dramatic effect of styrene on the enantioselectivity

被引：49

作者：

Li, Kangying ^{[1
]}

Alexakis, Alexandre ^{[1
]}

机构：

[1] Univ Geneva, Dept Chim Organ, CH-1211 Geneva 4, Switzerland

来源：

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION | 2006年 / 45卷 / 45期

关键词：

asymmetric synthesis; conjugate addition; copper; homogeneous catalysis; radicals;

D O I：

10.1002/anie.200602417

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

A simple trick could prove generally valuable for asymmetric copper-catalyzed conjugate addition reactions. It was found that the enantioselectivities of such reactions of dialkyl zinc reagents with α-halo enones in the presence of chiral phosphorimidite ligands were dramatically improved upon the addition of styrene, which acts as a radical scavenger to suppress the competitive non-asymmetric radical pathway (see example). (Chemical Equation Presented) © 2006 Wiley-VCH Verlag GmbH &. Co. KGaA.

引用

页码：7600 / 7603

页数：4

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