Dibenzopyran derivatives are prepared by palladium- and norbornene-catalyzed reaction of aryl iodides, o-substituted with electron-releasing substituents, o-bromophenols, and activated alkenes.
Sequential unsymmetrical aryl coupling of o-substituited aryl iodides with o-bromophenols and reaction with olefins: palladium-catalyzed synthesis of 6H-dibenzopyran derivatives / Motti, Elena; Faccini, F; Ferrari, I; Catellani, Marta; Ferraccioli, R.. - In: ORGANIC LETTERS. - ISSN 1523-7060. - 8(2006), pp. 3967-3970. [10.1021/ol061443w]