Enantioselective Squaramide-Catalysed Domino Mannich-Cyclization Reaction of Isatin Imines
作者:Xi-Bo Wang、Tian-Ze Li、Feng Sha、Xin-Yan Wu
DOI:10.1002/ejoc.201301350
日期:2014.2
An enantioselectivedominoreaction of 4-bromo-3-oxobutanoates with isatin-derived ketimines was developed to construct 3-amino-2-oxindoles with a quaternary stereocentre. In the presence of 1 mol-% of a bifunctional squaramide organocatalyst, the desired products were achieved in high yields (90–97 %) and with excellent enantioselectivities (92–99 % ee).