Gold-Catalyzed Cascade Friedel-Crafts/Furan-Yne Cyclization/Heteroenyne Metathesis for the Highly Efficient Construction of Phenanthrene Derivatives

A rapid access to highly substituted phenanthrenyl ketones through gold-catalyzed cyclization of 1,6-diyn-4-en-3-ols with furans has been developed. Gold catalysts are effective to catalyze three cascade processes involving Friedel-Crafts/furan-yne cyclization/heteroenyne metathesis through C-O bond and alkyne activation. This method offers several advantages such as high selectivities and easily accessible starting materials.