Functionalized ionic liquid as an efficient and recyclable reaction medium for phosphine-free palladium-catalyzed Heck reaction

摘要

A functionalized ionic liquid, 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([HEmim][BF4]), Was found to be as an efficient and recyclable reaction medium for palladium-catalyzed Heck reaction. The olefination of iodoarenes and bromoarenes with olefins generated the corresponding products in good to excellent yields under phosphine-free reaction conditions. The reaction involved the use of [HEmim][BF4] as the solvent, potassium phosphate as the base, and palladium acetate as the catalyst. In addition, palladium and ionic liquid could be recovered and recycled for six consecutive trials without significant loss of its reactivity.