Bicyclic-guanidine-catalyzed asymmetric Michael addition of 3-substituted oxindoles to 2-cyclopentenone

Abstract

Taking the Michael: The first highly enantio- and diastereoselective Michael addition of various 3-benzyl-substituted oxindoles to 2-cyclopentenone has been developed. A variety of 3,3-disubstituted oxindoles as Michael adducts were obtained in 69–99 % yield with 73–98 % ee and 9:1 to >20:1 d.r.