A double Mannich approach to the synthesis of substituted piperidones-application to the synthesis of substituted E-ring analogues of methyllycaconitine

Abstract

The double Mannich reaction of acyclic alpha,gamma-substituted beta-keto esters and bis(aminol) ethers gives substituted 3,5-substituted-4-piperidones with high levels of diastereoselectivity. These piperdiones can be easily transformed into substituted E-ring analogues of the delphinium alkaloid methyllycacotine. (C) 2010 Elsevier Ltd. All rights reserved.