Structure-reactivity studies of simple 4-hydroxyprolinamide organocatalysts in the asymmetric Michael addition reaction of aldehydes to nitroolefins

Abstract

A series of simple 4-hydroxyprolinamides was synthesised and they were found to act as organocatalysts for the asymmetric conjugate addition of aldehydes to nitroolefins in excellent yields (98%), with complete diastereoselectivity (99:1, syn:anti) and enantioselectivity (98% ee for syn). Furthermore, the use of low catalyst loadings (5mol%) and a low aldehyde molar excess (1.5equivalents) were achieved. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.