Organocatalytic Michael addition of malonates to isatylidene-3-acetaldehydes: application to the total synthesis of (-)-debromoflustramine E.

Flustering oxindoles: An enantioselective synthesis of 3,3'-disubstituted oxindoles by conjugate addition of malonates to isatylidene-3-acetaldehydes in high yield and enantioselectivity is developed (see scheme). The synthetic utility of this reaction is demonstrated by the synthesis of three oxindole core structures and the asymmetric total synthesis of debromoflustramine E.