Organocatalytic Enantioselective Cross-Dehydrogenative Coupling of <i>N</i>-Carbamoyl Cyclic Amines with Aldehydes
作者:Zhiyu Xie、Xin Zan、Shutao Sun、Xinhui Pan、Lei Liu
DOI:10.1021/acs.orglett.6b01625
日期:2016.8.19
existing catalytic enantioselective cross-dehydrogenativecoupling of cyclic amines predominantly focused on reactive N-aryl tetrahydroisoquinolines, which typically suffered from limited substrate generality and synthetic utility, and required the use of metal catalyst. Herein, a metal-free catalytic enantioselective cross-dehydrogenativecoupling of N-carbamoyl cyclic amines and aldehydes has been reported
A metal-free cross-dehydrogenative coupling of N-carbamoyl tetrahydroisoquinoline with a variety of C-H nucleophiles mediated by Na2S2O8 is developed. The reaction proceeds smoothly to give the coupled product in up to 83% yields. The nucleophile scope is broad, including simple ketones, aldehydes, and aryl rings. The carbamoyl protecting group can be readily removed under mild condition. The use of Na2S2O8 as the sole reagent for the CDC reaction is attractive based on economical and environmental factors. (C) 2014 Elsevier Ltd. All rights reserved.