I 2 -Mediated [6 + 1] Annulation of Alkynes with MsONH 3 OTf: Direct Synthesis of Benzo[ b ]azepines.

The synthesis of benzo[ b ]azepines using protonated aminating reagent (MsONH 3 OTf) and alkynes through I 2 -mediated [6 + 1] annulation reaction has been developed. This protocol features excellent functional group tolerance and mild reaction conditions and affords the benzo[ b ]azepines in moderate to good yields under metal-free reaction conditions.