Direct and Enantioselective Aldol Reactions Catalyzed by Chiral Nickel(II) Complexes

A direct and asymmetric aldol reaction of N-acyl thiazinanethiones with aromatic aldehydes catalyzed by chiral nickel(II) complexes is reported. The gives the corresponding O-TIPS-protected anti-aldol adducts in high yields remarkable stereocontrol atom economy. Furthermore, straightforward removal achiral scaffold provides enantiomerically pure intermediates synthetic interest, which involve precursors for anti-?-amino-?-hydroxy ?,?-dihydroxy carboxylic derivatives. Theoretical calculations explain observed stereocontrol.