Synthesis of Functionalized Benzopyran/Coumarin-Derived Aryne Precursors and Their Applications.

An efficient synthetic method of benzopyran derivatives involving coumarins is disclosed. Gold-catalyzed benzopyran formation and subsequent aryne reactions enabled us to prepare a wide range of benzopyran derivatives by virtue of their good functional group tolerance and versatile transformability of aryne intermediates. The synthetic utility was showcased by a diarylnaphthopyran synthesis through this method and consecutive cross-coupling reactions.