Asymmetric Synthesis of Functionalized Tertiary Alcohols by Diastereoselective Aldol Reaction of Silyl Enol Ether and Ketene Silyl Acetal with α-Keto Esters Bearing an Optically Active Cyclitol as a Chiral Auxiliary

Abstract

Tin (IV) chloride promoted aldol reactions of silyl enol ether and ketene silyl acetal with α-keto esters derived from L-quebrachitol afforded the corresponding aldol-type adduct, α-hydroxy acid derivatives, in good yields with excellent diastereomeric excesses.