title: Enhanced hydrolytic activity of Cu(II) and Zn(II) complexes in highly cross-linked polymers.
abstract: The chelate ligand tris[(1-vinylimidazol-2-yl)methyl]amine (5) was synthesized in five steps from commercially available starting materials. Upon reaction with ZnCl2 or CuCl2 in the presence of NH4PF6, the complexes [Zn5Cl]PF6 (6) and [Cu5Cl]PF6 (7) were obtained. The structure of both complexes was determined by single-crystal X-ray crystallography. Immobilization of 6 and 7 was achieved by co-polymerization with ethylene glycol dimethacrylate. The supported complexes P6-Zn and P7-Cu were found to be efficient catalysts for the hydrolysis of bis(p-nitrophenyl)phosphate (BNPP) at 50 degrees C. At pH 9.5, the heterogeneous catalyst P7-Cu was 56 times more active than the homogeneous catalyst 7. Partitioning effects, which increase the local concentration of BNPP in the polymer, are shown to contribute to the enhanced activity of the immobilized catalyst.
authors.affiliation: Institut des Sciences et Ingénieries Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Alexander
authors.initials: A
authors.lastname: Schiller
authors.forename: Rosario
authors.initials: R
authors.lastname: Scopelliti
authors.forename: Kay
authors.initials: K
authors.lastname: Severin
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006868:Hydrolysis; D007700:Kinetics; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D011108:Polymers; D003300:Copper; D015032:Zinc