Gold-catalyzed approach to multisubstituted fulvenes via cycloisomerization of furan/ynes.

A new approach to functionalized fulvenes with an enone or enal moiety has been developed through gold-catalyzed intramolecular cycloisomerization of furan/ynes with a two-carbon tether in between the furan and the triple bond. The reaction proceeds with complete regioselectivity via a 6-endo-cyclization and high stereoselectivity. Moreover, the E- or Z-stereochemistry of the double bond in fulvene products can be easily controlled by performing the reaction in different solvents.