The Crabtree Group developed the [(cod)IrLL']PF6 series of catalysts, where L is a P-donor such as PCy3 and L' and N-donor such as pyridine. These are very active in the hydrogenation of sterically hindered alkenes. The catalyst also shows directing effects as a result of binding of the catalyst to suitable functional groups on the substrate, followed by addition of H2 from the same side of the substrate that the functional group is located. Two versions of the catalyst are available; one with PF6 and the other with BArF4 counteranion.
Crabtree Group Website