THE PREPARATION OF OPTICALLY ACTIVE β-KETO SULFOXIDES BY THE REACTION OF α-LITHIOMETHYL p-TOLYL SULFOXIDE WITH ETHYL CARBOXYLATES IN THE PRESENCE OF (—)-SPARTEINE

Abstract

Treatment of 2 equivalents of racemic α-lithiomethyl p-tolyl sulfoxide (1) with ethyl carboxylates (2, C₂H₅O—CO—R) possessing a variety of groups R in the presence of (−)-sparteine afforded the corresponding optically active β-keto sulfoxides (3, p-CH₃C₆H₄—SO—CH₂—CO—R) together with optically active methyl p-tolyl sulfoxide which has the opposite configuration to 3.