An asymmetric reductive amination of ketones using both arylamines and benzhydrazide in the presence of nickel catalysts was developed. A one‐pot synthesis of tetrahydroquinoxalines was also developed starting directly from α‐ketoaldehydes and 1,2‐diaminobenzene. Formic acid was used as a safe and economic surrogate for high‐pressure hydrogen gas. Strongly σ‐donating bis(alkylphosphine)s are crucial
An asymmetrichydrogenation of hydrazones with a unique nickel catalyst has been developed for the synthesis of chiral hydrazines with up to 99 % yield and 99.4 : 0.6 er and a broad substrate scope. Deuterium labelling experiments indicated that the hydrazone substrates undergo imine-enamine tautomerization in the mixed solvents.
An efficient cobalt-catalyzed asymmetric reductive amination of ketones with hydrazides has been realized, directly producing valuable chiral hydrazines in high yields and enantioselectivities (up to 98% enantiomeric excess).
Nickel-catalyzed enantioselective reductive amination of benzylic ketones in alcohols
作者:Xiuhua Wang、Jianrong Steve Zhou
DOI:10.1007/s11426-024-2019-1
日期:2024.8
Asymmetricreductive amination directly converts ketones and amines to alkylamines, which are important motifs in medicines. We report that cationic nickel complexes of chiral diphosphines promote enantioselective reductive amination of benzylic ketones with both arylamines and benzhydrazide. Isopropanol was used as a safe and cheap source of hydrogen instead of formic acid. The reaction can be readily