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

• DOI: 10.1021/acs.orglett.8b02503
• Publication Date: 2018-10-02T14:27:16Z
• Authors: Zhengyu Han; Yu-Qing Guan; Gang Liu; Rui Wang; Xuguang Yin; Qingyang Zhao; Hengjiang Cong; Xiu-Qin Dong; Xumu Zhang
• Keywords: 01 natural sciences; 0104 chemical sciences

An iridium-catalyzed highly efficient asymmetric hydrogenation of challenging tetrasubstituted α-fluoro-β-enamino esters was successfully developed using bisphosphine-thiourea (ZhaoPhos) as the ligand, which prepared a series of chiral α-fluoro-β-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.