Efficient Palladium-Catalyzed Coupling of Aryl Chlorides and Tosylates with Terminal Alkynes: Use of a Copper Cocatalyst Inhibits the Reaction

Less catalyst, lower temperature, and greater generality are the advantages of the new general protocol over those previously described for the palladium-catalyzed coupling of aryl chlorides and alkynes (see scheme). Better results are obtained without a copper cocatalyst, which has been found to inhibit product formation in the coupling reaction of aryl chlorides with terminal alkynes.