Highly enantio- and diastereoselective synthesis of α-trifluoromethyldihydropyrans using a novel bifunctional piperazine-thiourea catalyst

Abstract

The first enantioselective Michael addition of α-cyanoketones to α,β-unsaturated trifluoromethyl ketones using a novel piperazine-thiourea catalyst was described. The resulting α-trifluoromethyldihydropyrans were obtained in high yields and with up to 95% ee within a short reaction time. A useful transformation of the chiral adduct was also illustrated.