Organocatalytic Michael Addition of Indoles to Isatylidene-3-acetaldehydes: Application to the Formal Total Synthesis of (−)-Chimonanthine

A novel strategy for the enantioselective synthesis of 3,3′-disubstituted oxindoles by the organocatalytic Michael addition of indoles to isatylidene-3-acetaldehydes was developed, which can be used for the formal total synthesis of (−)-chimonanthine and the core structure construction of (+)-gliocladin C.