Effect of amine structure and reaction additives on enantioselective deprotonations mediated by homochiral magnesium amide bases

被引：20

作者：

Anderson, JD

García, PG

Hayes, D

Henderson, KW

Kerr, WJ

Moir, JH

Fondekar, KP

机构：

[1] Univ Strathclyde, Dept Pure & Appl Chem, Glasgow G1 1XL, Lanark, Scotland

[2] GlaxoSmithKline, Med Res Ctr, Stevenage SG1 2NY, Herts, England

来源：

TETRAHEDRON LETTERS | 2001年 / 42卷 / 40期

基金：

英国工程与自然科学研究理事会;

关键词：

additives; asymmetric synthesis; chiral amines; enantioselective deprotonation; magnesium;

D O I：

10.1016/S0040-4039(01)01465-4

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

A series of novel. optically pure, Mg-bisamides have been prepared and. in turn, used to mediate enantioselective deprotonations of conformationally locked ketones. The new bases exhibit a wide range of selectivities, from poor to excellent (up to 95:5 e.r.); trends between amine structure and the subsequent selectivity of the deprotonation system are detailed. In addition, the effects on the selectivity and the reactivity of the deprotonation process on replacing the Lewis base additive HMPA for DMPU have been investigated and found to be related to the reaction temperature. (C) 2001 Elsevier Science Ltd. All rights reserved.

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页码：7111 / 7114

页数：4

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