Synthesis and Enhanced Activity of Etherlized Ferrocenylphosphine for the Palladium-Catalyzed Suzuki Reaction

A new etherlized ferrocenylphosphine ligand,2-diphenylphosphino-ferrocenyl-ethyl-5-hydroxyl-3-oxo-pentyl ether,was prepared by the reaction of acetyl 1-(diphenylphosphinoferrocenyl)ethyl ester with diethylene glycol in 77% yield.Its structure was characterized by 1H NMR,13C NMR,31P NMR and MS.The synthesized ferrocenylphosphine has been applied as supporting ligand in the palladium-catalyzed Suzuki reaction;its ligated palladium catalyst is effective for coupling a range of aryl bromides as well as aryl chlorides having electron-withdrawing groups with phenylboronic acid to prepare the corresponding biaryls.The possible coordination of ether-oxygen to the Pd center may enhance the catalytic performance of the ligand for cross-coupling reaction.