A useful diastereoselectivesynthesis of aldolsusingchiral 3-acyl-1,3-oxazlidine-2-thiones, (1), (4), (7), and (9), is reported and its application to the synthesis of a chiral azetidinone (11) is described.
New C-4-chiral 1,3-thiazolidine-2-thiones: excellent chiral auxiliaries for highly diastereo-controlled aldol-type reactions of acetic acid and .alpha.,.beta.-unsaturated aldehydes