Enantioselective addition of a chiral thiazolidinethione-derived titanium enolate to acetals.

[reaction: see text] High stereoselectivities (up to 98% de) have been achieved for the Lewis acid-mediated cross-coupling reaction of dimethyl acetals to a chiral 1,3-thiazolidine-2-thione-derived titanium enolate. The reaction affords enantiopure anti alpha-methyl-beta-alkoxy carbonyl compounds in a wide range of acetals.