Organocatalytic asymmetric decarboxylative addition of b-ketoacids to methyleneindolinones derivatives

Abstract

The quinine squaramide-catalyzed enantioselective decarboxylative addition reaction of various -keto acids with methyleneindolinones has been developed. Through this methodology, various oxindole derivatives were synthesized in good yields (up to 93 %) and excellent enantiomeric excess (up to 99 % ee) and moderate diastereoselectivity (up to 66:34).