Synthesis of Dibenzazepinones by Palladium-Catalyzed Intramolecular Arylation of o-(2′-Bromophenyl)anilide Enolates

A new approach for the convenient synthesis of dibenzazepinones is reported. The key step is the formation of the seven-membered ring through palladium-catalyzed intramolecular arylation of an anilide enolate. The reactions were completed in 10 min at 100 degrees C with moderate to excellent yields. Aminodibenzazepinone 1, the core structure in the gamma-secretase inhibitor LY411575, can be prepared in five steps from 2-bromophenylboronic acid and 2-iodoaniline in 60% overall yield. The synthesis reported here compares favorably with presently available approaches to this interesting ring system.