Asymmetric cross aldol addition of isatins with α,β-unsaturated ketones catalyzed by a bifunctional Brønsted acid–Brønsted base organocatalyst
作者:Guo-Gui Liu、Hua Zhao、Yu-Bao Lan、Bin Wu、Xiao-Fei Huang、Jian Chen、Jing-Chao Tao、Xing-Wang Wang
DOI:10.1016/j.tet.2012.03.042
日期:2012.5
The asymmetric cross-aldol reaction of isatins with α,β-unsaturated ketones has been developed under catalysis by a Cinchona alkaloid-derivated bifunctional Brønsted acid–Brønsted base catalyst, affording the aldol adducts in moderate to good yields (18–98%) with moderate to good enantioselectivities (30–97%). The noncovalent organo-catalyzed asymmetric cross-aldol reaction displays a broad substrate