Application of P,N-Sulfinyl Imine Ligands to Iridium-Catalyzed Asymmetric Hydrogenation of Olefins

The utility of a novel class of P,N-ligands incorporating a chiral sulfinyl imine moiety is demonstrated in the iridium-catalyzed hydrogenation of both functionalized and unfunctionalized olefins, in which enantioselectivities of up to 94% are achieved. The modularity of the P,N-sulfinyl ligand class is highlighted by the facile preparation of a variety of sterically and electronically different ligands. Interesting structure-activity data for both the phosphine and sulfinamide components is provided by this expanded ligand set.