BIFUNCTIONAL CHIRAL AUXILIARIES .7. ALDOL REACTIONS OF ENOLATES DERIVED FROM 1,3-DIACYLIMIDAZOLIDINE-2-THIONES AND 1,3-DIACYLIMIDAZOLIDIN-2-ONES

被引：32

作者：

DAVIES, SG

EDWARDS, AJ

EVANS, GB

MORTLOCK, AA

机构：

[1] The Dyson Perrins Laboratory, University of Oxford, Oxford, OX1 3QY, South Parks Road

来源：

TETRAHEDRON | 1994年 / 50卷 / 22期

关键词：

D O I：

10.1016/S0040-4020(01)89691-5

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Dibutylboron enolates of 1,3-diacylimidazolidine-2-thiones and 1,3-diacylimidazolidin-2-ones undergo highly syn-stereoselective aldol reactions with aldehydes to allow elaboration of both acyl sidechains. The reaction is proposed to occur via sequential enolisation rather than via a bisenolate and the stereochemistry of the product was elucidated by both X-ray crystallography and reductive cleavage of a homochiral aldol product to give (1R,2S)-1-phenyl-2-methylpropane-1,3-diol. In contrast, tin (II) triflate mediated aldol reactions result in only one of the two acyl sidechains reacting and exhibit reversed enantiofacial stereoselectivity.

引用

页码：6621 / 6642

页数：22

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