Microwave-assisted, Copper-free Sonogashira Coupling Between Aryl Halides and Terminal Alkynes Using Recyclable Ionic Liquid and Catalyst

An efficient method for the Sonogashira coupling reaction between aryl halides and terminal alkynes has been developed. The reaction was performed in ionic liquid 1-butyl-3- methylimidazolium tetrafluoroborate ([Bmim][BF4]) under microwave irradiation. High yields of products were obtained in a very short reaction time. Moreover, the medium and catalyst could be recovered and reused three times without considerable decrease in reaction yields.