Sequential Unsymmetrical Aryl Coupling of o-Substituted Aryl Iodides with o-Bromophenols and Reaction with Olefins:  Palladium-Catalyzed Synthesis of 6H-Dibenzopyran Derivatives

Dibenzopyran derivatives are prepared by palladium- and norbornene-catalyzed reaction of aryl iodides, o-substituted with electron-releasing substituents, o-bromophenols, and activated alkenes.