Catalytic Enantioselective Epoxidation of Homoallylic Alcohols by Chiral Zirconium Complexes.

Catalytic enantioselective epoxidation of homoallylic alcohols using Zr(Ot-Bu)4 and tartrate ester (or tartramide) has been developed. In the Zr(Ot-Bu)4/diisopropyl tartrate-catalyzed epoxidation, the reverse of the enantiofacial preference was observed, depending on the Zr/ligand ratios of 1:1 or 1:2.