Ir‐SpinPHOX Catalyzed Enantioselective Hydrogenation of 3‐Ylidenephthalides

Abstract The first asymmetric hydrogenation of 3‐ylidenephthalides has been developed using the Ir I complex of a spiro[4,4]‐1,6‐nonadiene‐based phosphine‐oxazoline ligand (SpinPHOX) as the catalyst, affording a wide variety of chiral 3‐substituted phthalides in excellent enantiomeric excesses (up to 98 % ee ). The utility of the protocol has been demonstrated in the asymmetric synthesis of chiral drugs NBP and BZP precursor, as well as the natural products chuangxinol and typhaphthalide.