Organic letters

The enantioselective Birch-Cope sequence for the synthesis of carbocyclic quaternary stereocenters. Application to the synthesis of (+)-mesembrine

T Paul, WP Malachowski, J Lee

Index: Paul, Tapas; Malachowski, William P.; Lee, Jisun Organic Letters, 2006 , vol. 8, # 18 p. 4007 - 4010

Full Text: HTML

Citation Number: 28

Abstract

A synthetic technique for generating carbocyclic quaternary stereocenters with exceptionally high levels of enantioselectivity is described. A sequence of three reactions, enantioselective Birch reduction-allylation, enol ether hydrolysis, and Cope rearrangement, is used to stereoselectively generate chiral quaternary centers on a 2-cyclohexen-1-one ring. The products of the sequence are 4, 4-disubstituted-2-carboxamide-2-cyclohexen-1- ...