title: Polymer-supported N-heterocyclic carbene-palladium complex for heterogeneous Suzuki cross-coupling reaction.
abstract: Poly(1-methylimidazoliummethyl styrene)-surface grafted-poly(styrene) resin was prepared for the first time as a polymer-supported N-heterocyclic carbene (NHC) precursor for palladium complex by suspension polymerization. To prepare this polymer-supported NHC precursor, 1-methyl-3-(4-vinylbenzyl)imidazolium hexafluorophosphate, [MVBIM][PF6-], was synthesized as a monomer and copolymerized with styrene and DVB in water. This polymer-supported NHC precursor with imidazolium as a ligand, which exists solely on the surface of the resin, was well characterized by FE-SEM, CLSM, and IR spectroscopy. The precursor containing imidazolium readily formed a stable complex with Pd(OAc)2, and this polymer-supported N-heterocyclic carbene-palladium complex exhibited excellent catalytic activity for Suzuki cross-coupling reaction in an aqueous medium. The catalyst was recovered quantitatively from the reaction mixture by simple filtration and was able to be reused for a number of recycles with consistent activity in all of the coupling reactions.
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, Korea.
authors.forename: Jong-Ho
authors.initials: JH
authors.lastname: Kim
authors.forename: Jung-Woo
authors.initials: JW
authors.lastname: Kim
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Shokouhimehr
authors.forename: Yoon-Sik
authors.initials: YS
authors.lastname: Lee