Dynamic Kinetic Resolution of α‑Trifluoromethyl Hemiaminals without α‑Hydrogen via NHC-Catalyzed O‑Acylation
journal contributionposted on 2021-02-03, 16:35 authored by Yuan-Yuan Gao, Chun-Lin Zhang, Lei Dai, You-Feng Han, Song Ye
Following the well-recognized dynamic kinetic resolution (DKR) of hemiaminals with α-hydrogen under lipase and chiral DMAP catalysis, the unprecedented DKR of hemiaminals without α-hydrogen was developed via N-heterocyclic carbene catalyzed O-acylation of 3-hydroxy-3-trifluoromethylbenzosultams. The racemic hemiaminals without α-hydrogen were effectively racemized and differentiated by chiral NHCs under basic conditions. The resulting esters were obtained in high yields with good to high enantioselectivities.