Discovery of an iridacycle catalyst with improved reactivity and enantioselectivity in the hydrogenation of dialkyl ketimines

Catalytically active iridacycles are formed by cyclometalation of acetophenone imines with Ir-PHOX complexes under hydrogen atmosphere. These complexes show unusually high reactivity and enantioselectivity in the hydrogenation of alkyl methyl ketimines. The structure of the cyclometalated imine has a strong effect on the conversion and enantiomeric excess.