Synthesis of 3-Benzazepines via Cobalt-Catalyzed C–H Bond Functionalization with CaC₂ as the Acetylene Source

Herein, we report a simple method for the synthesis of 3-benzazepine derivatives via a cobalt-catalyzed, picolinamide-directed α-amidoacrylate C(sp²)-H bond functionalization approach. The reactions utilize calcium carbide as an inexpensive, easy-to-handle, and solid acetylene source, and simple CoCl₂ as the reaction catalyst. Excellent functional group tolerance is observed, yielding diverse substituted 3-benzazepine derivatives in good to excellent yields.