Hybrid Heterocycles: Ag(I)-Catalyzed C–C/C–N/C–O Coupled Cascade Dual Cyclization to Valuable Indolo-4H-indolones and Indolo-4H-chromenes

Herein, we report a highly efficient Ag(I)-catalyzed indolyzation with Friedel–Crafts alkylation through a cascade cyclization strategy for accessing valuable hybrid heterocycles for the first time. This general strategy consists of forming four C–C/C–N/C–O bonds toward dual annulation reactions of 2-alkynylanilines with methyl benzoate-2-carboxaldehydes and aromatic amines, as well as with salicylaldehydes and malononitrile. Variably substituted new indolo-4H-phthalimidines and indolo-4H-chromenes were synthesized with excellent yields (85–93%) under mild reaction conditions.