Gold-catalyzed Tandem Reaction of O-Alkynylphenols with Diazo Compounds: Access to 2,3-Disubstituted Benzofurans.

A gold-catalyzed tandem reaction of o-alkynylphenols with diazo compounds has been developed, providing the 2,3-disubstituted benzofurans in moderate to good yields under mild reaction conditions. In this protocol, the vinyl gold and gold carbene species might form during the reaction process. Control experiments have been performed to understand the reaction mechanism.