Novel chemoselective tosylation of the alcoholic hydroxyl group of syn-α,β-disubstituted β-hydroxy carboxylic acids

Abstract

β-Hydroxy acids were readily converted into β-tosyloxy acids (hydroxyl group activation) in moderate to excellent yields via the O,O-dianions generated by treatment with methyllithium and thus make it possible to prepare anti α,β-disubstituted β-lactones directly from the syn aldols.