Gold-catalyzed carbocyclization of phenols with a terminal alkyne via an intramolecular ipso-friedel-crafts alkenylation

Abstract

We have developed a novel synthetic method to furnish spiro[4.5] cyclohexadienones using an gold-catalyzed carbocyclization of phenols with a terminal alkyne via an intramolecular ipso-Friedel-Crafts alkenylation. Using 2-5mol% of gold catalyst, 1equiv. of methanesulfonic acid, and 1equiv. of 2,6-di-tert-butylpyridine, a variety of spiro[4.5]cyclohexadienone derivatives with an exo-cyclic olefin unit was obtained in good to excellent yields. The divergent synthesis of dihydronaphthalene derivatives was also examined based on the newly developed gold catalysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.