Enantioselective synthesis of 2-amino-3-nitrile-chromenes catalyzed by cinchona alkaloids: A remarkable additive effect
摘要:
2-Amino-3-nitrile-chromenes with potential antitumor activity were constructed by a novel catalytic system. In combination with alpha-naphthol, quinine could effectively promote the Michael-cyclization process of malononitrile with functionalized chalcones in high yields and moderate to good enantioselectivity (up to 84% ee). It is notable that the enantioselectivity could be greatly improved when a-naphthol was employed as additive. (C) 2015 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.
Squaramide-catalyzed enantioselective Michael addition of malononitrile to chalcones
作者:Wen Yang、Yang Jia、Da-Ming Du
DOI:10.1039/c1ob06302b
日期:——
A highlyenantioselective Michael addition of malononitrile to chalconescatalyzed by a chiral quinine-derived squaramide catalyst has been developed. This organocatalytic reaction at a very lowcatalystloading (0.5 mol%) led to chiral γ-cyano carbonyl compounds in good yields with high enantioselectivities (up to 96% ee) under mild reaction conditions.