Palladium‐Catalyzed [4 + 2] Annulative Coupling Between 1,3‐Butadienes and 2‐Haloarylsulfonamides: En‐Route to Benzosultam Scaffolds

Herein, we have demonstrated a palladium‐catalyzed [4 + 2] annulation reaction to acquire benzosultam frameworks from readily accessible 2‐iodo‐arylsulfonamides and feedstock material 1,3‐butadienes. The synthetic transformation involves consecutive CC and CN bond formations by following intermolecular Heck‐type coupling and intramolecular Tsuji–Trost allylic amination via a transient π‐allyl‐Pd‐intermediate to enable benzosultams. Operational simplicity, broad substrate scope, viability of functional groups, scalability, and further synthetic transformations are the significance of the protocol.