Zinc triflate–bis-oxazoline complexes as chiral catalysts: enantioselective reduction of α-alkoxy-ketones with catecholborane

A new methodology for the catalytic enantioselective reduction of α-alkoxy-ketones is described. The procedure employes Zn(OTf)2–bis-oxazoline complexes (8–10 mol%) as catalysts and catecholborane as the reducing agent. The reaction, carried out in CH2Cl2 at 0°C, affords the α-alkoxy-alcohols in high yields and with good enantioselectivity.