Synthesis of 6-Phenanthridinones and Their Heterocyclic Analogues through Palladium-Catalyzed Sequential Aryl−Aryl and N-Aryl Coupling

6-Phenanthridinones and their heterocyclic analogues were synthesized through a one-pot procedure based on consecutive Pd-catalyzed aryl−aryl and N-aryl coupling from iodoarenes ortho-substituted by electron-releasing substituents and amides of o-bromoarene- and heteroarenecarboxylic acids.