Fused oxindoles are the core structures of the naturally occurring oxindole alkaloids, and the fused tricyclic structures have distinguished themselves with unique biological activities. Herein, we developed a synthetic strategy for divergent synthesis of diverse types of [3,4]-seven-or six-membered ringfused 3-alkenyl-oxindoles incorporating benzazepine and significant building blocks from propargyl alcohols via the cascade nucleophilic substitution/site-selective hydride transfer/cyclization process unprecedentedly. In addition, a variety of nucleophiles, including H 2 O, were available for controllable construction of a wide range of conjugated alkenes, conjugated ketones, and allyl alcohols encompassing natural products and pharmaceutical motifs with the utilization of 4-amine substituted isatins and widespread terminal alkyne-derived propargyl alcohols. Furthermore, the synthetic utility of the methodology and mechanistic studies also were well presented.

The three-component reaction of o-aminobenzaldehydes with 5-hydroxyindole and electron-rich arenes has been achieved through HFIP-mediated cascade hydride transfer/dearomative cyclization/CDC-type imidization at room temperature under air.

An efficient approach to achieve the divergent α-C(sp3)–H functionalization of cyclic amines through an O2 oxidized dearomatization/ring construction and aromatization-driven ring deconstruction/intermolecular functionalization strategy was developed.