Iridium-Catalyzed Asymmetric Hydrogenation of Tetrasubstituted alpha-Fluoro-beta-enamino Esters: Efficient Access to Chiral alpha-Fluoro-beta-amino Esters with Two Adjacent Tertiary Stereocenters

An iridium-catalyzed highly efficient asymmetric hydrogenation of challenging tetrasubstituted alpha-fluoro-beta-enamino esters was successfully developed using bisphosphine-thiourea (ZhaoPhos) as the ligand, which prepared a series of chiral alpha-fluoro-beta-amino esters containing two adjacent tertiary stereocenters with high yields and excellent diastereoselectivities/enantioselectivities (73%-99% yields, >25:1 dr, 91%-> 99% ee, and turnover number (TON) values up to 8600), and no defluorinate byproduct was detected.