不对称串联维蒂希重排/羟醛缩合反应。

Asymmetric tandem wittig rearrangement/Aldol reactions.

作者信息

Giampietro Natalie C, Kampf Jeff W, Wolfe John P

机构信息

Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, USA.

出版信息

J Am Chem Soc. 2009 Sep 9;131(35):12556-7. doi: 10.1021/ja905930s.

DOI:10.1021/ja905930s

PMID:19678705

Abstract

A new method for the asymmetric synthesis of alpha-alkyl-alpha,beta-dihydroxy esters that involves tandem Wittig rearrangement/aldol reactions of O-benzyl- or O-allylglycolate esters derived from 2-phenylcyclohexanol is described. This sequence constructs two C-C bonds and two stereocenters, one of which is quaternary, to afford syn diol products with excellent stereocontrol. Cleavage of the chiral auxiliary affords enantiomerically enriched products with up to 95% ee. The application of this method to the preparation of a key intermediate in the synthesis of the antifungal agent alternaric acid is also described.

摘要

描述了一种用于不对称合成α-烷基-α,β-二羟基酯的新方法，该方法涉及由2-苯基环己醇衍生的O-苄基或O-烯丙基乙醇酸酯的串联维蒂希重排/羟醛反应。该序列构建了两个C-C键和两个立体中心，其中一个是季碳中心，以提供具有优异立体控制的顺式二醇产物。手性助剂的裂解得到对映体富集的产物，对映体过量高达95%。还描述了该方法在制备抗真菌剂交替链格孢酸合成中的关键中间体的应用。