2-Lithio-N-BOC-thiazolidines as chiral acyl anion synthons: evaluation of facial stereoselectivity in the addition of chiral organolithiums to aldehydes

Abstract

Deprotonation of N-BOC-thiazolidines having an isopropyl group in the 4- or 5-position affords chiral organolithiums that add to aldehydes in excellent yields. The relative and absolute configurations at both new stereocenters of the major and minor isomers were deduced. Mechanistic considerations suggest that each organolithium adds with a high degree of diastereoselectivity. We also demonstrated, as proof of principle, that further elaboration of the addition products into α-hydroxyaldehydes and glycols can be achieved.