InBr3‐ and AgOTf‐catalyzed beckmann rearrangement of (E)‐benzoheterocyclic oximes

Beckmann rearrangement of (E)‐4‐chromanone oxime, (E)‐5‐oximino‐3,4‐dihydro‐1(2H)‐benzoxepines, and (E)‐5‐oximino‐3,4‐dihydro‐1(2H)‐benzothiepine are catalyzed by InBr₃ and AgOTf in refluxing acetonitrile resulting in the formation of pharmaceutically active heterocycles benzoxazepin‐4‐one, 5‐oxo‐benzoxazocines, and 5‐oxo‐benzothiazocine derivative, respectively, in excellent yield. J. Heterocyclic Chem., (2012).