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

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