Manganese(I)-Catalyzed Asymmetric (Transfer) Hydrogenation of Simple Ketones by a Novel Chiral Tridentate P*NN Ligand

A novel chiral P*NN ligand featuring a P-chirality has been synthesized, and its catalytic properties in Manganese(I)-catalyzed asymmetric hydrogenation and asymmetric transfer hydrogenation of ketones are investigated. A broad range of substrates (42 examples) are hydrogenated, delivering a series of chiral alcohols with outstanding yields (>90%) and good enantioselectivities (up to 92% ee). In addition, a plausible catalytic cycle is performed through deuterium-labeling experiments and high-resolution mass spectrometry analysis.