Iridium-Catalyzed Enantioselective Hydrogenation of Indole and Benzofuran Derivatives.

Enantioselective hydrogenation of a broad spectrum of N-, O-, and S-containing aromatic benzoheterocycles or nonaromatic unsaturated heterocycles has been realized by using an Ir/SpinPHOX (SpinPHOX=spiro[4,4]-1,6-nonadiene-based phosphine-oxazoline) complex as the catalyst, affording an array of the corresponding chiral benzoheterocycles (30 examples) with excellent enantioselectivities (>99 % ee in most cases) and turnover numbers up to 500.