Controllable Synthesis of Benzo[<i>b</i>]furo[2,3-<i>d</i>]azepines or Furo[3,2-<i>b</i>]indoles via Intermolecular Oxidative Annulation of 2-(Furan-2-yl)anilines and Propargyl Carbonates versus Intramolecular C–H Amination Reactions

Two novel Pd-catalyzed protocols for the controllable synthesis of benzo[<i>b</i>]furo[2,3-<i>d</i>]azepines and furo[3,2-<i>b</i>]indoles have been developed by intermolecular oxidative annulation of 2-(furan-2-yl)anilines and propargyl carbonates versus intramolecular C-H amination reactions. These two protocols feature great scalability, functional group tolerance, and relatively mild reaction conditions. Notably, the robust methodologies could also provide valuable opportunities for assembling azepine-fused benzothiophene, indole-fused benzothiophene, and indole-fused benzimidazole, which may have potential applications in the synthesis of related pharmaceuticals or polymeric materials.