Synthesis of Bicyclic Enediynes from Bis[phenyl[(trifluoromethanesulfonyl)oxy]iodo]acetylene: A Tandem Diels-Alder/Palladium(II)- and Copper(I)-Cocatalyzed Cross-Coupling Approach.

The reaction of bicycloalkenylbis(phenyliodonium) triflates 1a or b (available via the Diels-Alder reaction of bis[phenyl[(trifluoromethanesulfonyl)oxy]iodo]acetylene with cyclopentadiene or furan, respectively) with alkynylstannanes 2a-g at room temperature in DMF in the presence of catalytic amounts of trans-benzyl(chloro)bis(triphenylphosphine)palladium(II) and copper(I) iodide proceeds smoothly and with selectivity to afford good to excellent yields of bicyclic enediynes 3a-k.