Asymmetric hydrogenation of α-hydroxy ketones catalyzed by MsDPEN-Cp*Ir(III) complex

Asymmetric hydrogenation of a series of alpha-hydroxy aromatic ketones in methanol catalyzed by Cp*Ir(OTf)(MsDPEN) (MsDPEN = N-(methanesulfonyl)-1,2-diphenylethylenediamine) affords the 1-aryl-1,2-ethanediols in up to 99% ee. The reaction can be conducted with a substrate-to-catalyst molar ratio as high as 6000 under 10 atm of H-2. 1-Hydroxy-2-propanone is also hydrogenated with high enantioselectivity.