Highly Efficient Rh-Catalyzed Asymmetric Hydrogenation of α,β-Unsaturated Nitriles

A highly efficient enantioselective hydrogenation of α,β-unsaturated nitriles catalyzed by Rh-(<i>R</i>,<i>R</i>)-f-spiroPhos complex has been developed. With Rh-(<i>R</i>,<i>R</i>)-f-spiroPhos catalyst and under mild conditions, a wide range of α,β-unsaturated nitriles including the (<i>E</i>)- and (<i>Z</i>)-isomers of 3-alkyl-3-aryl, 3,3-diaryl, and 3,3-dialkyl α,β-unsaturated nitriles were hydrogenated to the corresponding chiral nitriles with excellent enantioselectivities (up to 99.9% ee) and high turnover numbers (TON up to 10,000)