Sulfinamide Phosphinates as Chiral Catalysts for the Enantioselective Organocatalytic Reduction of Imines

A new type of chiral sulfinamide phosphinate catalysts with up to three stereogenic centers, readily accessible from commercially available starting materials, is reported. The naphthyl derivative SulPhos proved to be highly efficient in the organocatalytic asymmetric imine reduction, leading to a wide range of arylmethylamines in high yields with up to 99% ee under 10% catalyst loading. The synthetic utility of this method was demonstrated by the expeditious enantioselective synthesis of the calcirnimetic NPS-R568.