Direct Asymmetric Hydrogenation of N-Methyl and N-Alkyl Imines with an Ir(III)H Catalyst

Abstract

A novel cationic [IrH(THF)(P,N)(imine)] [BArF] catalyst contg. a P-stereogenic MaxPHOX ligand is described for the direct asym. hydrogenation of N-Me and N-alkyl imines. This is the first catalytic system to attain high enantioselectivity (up to 94% ee) in this type of transformation. The labile THF ligand allows for effective activation and reactivity, even at low temps. D. functional theory calcns. allowed the rationalization of the stereochem. course of the reaction.