Highly enantioselective synthesis of bisoxindoles with two vicinal quaternary stereocenters via Lewis base mediated addition of oxindoles to isatin-derived ketimines

Abstract

A highly efficient asymmetric organocatalytic addition of 3-substituted oxindole to isatin-derived ketimine is reported with excellent stereocontrol (>99 : 1 dr, >99% ee) under mild conditions. This method provides access to the bisoxindole structure moiety with two vicinal quaternary stereogenic centers.