Asymmetric Reduction of Trifluoromethyl Alkynyl Ketimines by Chiral Phosphoric Acid and Benzothiazoline

An enantioselective transfer hydrogenation reaction of alkynyl ketimine bearing a trifluoromethyl group was accomplished. Chemoselective reduction of ketimine was achieved by the combined use of chiral phosphoric acid and benzothiazoline to give -trifluoromethyl propargylamine in good to high yields and with excellent enantioselectivity.