摘要:
Delta-Hydroxy allylic phosphine oxides 5 undergo asymmetric epoxidation to yield epoxy alcohols 6 with high enantio- and diastereoselectivity. Kinetic resolutions are also successful, even with a chiral centre remote from the allylic hydroxyl, if that chiral centre bears a diphenylphosphinoyl group. The diphenylphosphinoyl group then exerts a novel anti-directing effect on the epoxidation.