Palladium-catalyzed intramolecular C-H arylation of 2-halo- N -Boc- N -arylbenzamides for the synthesis of N-H phenanthridinones.

A palladium catalyzed synthesis of N-H phenanthridinones was developed via C-H arylation. The protocol gives phenanthridinones regioselectively by one-pot reaction without deprotection. It exhibits broad substrate scope and affords targets in up to 95% yields. Importantly, it could be applied for the less reactive o -chlorobenzamides.