title: New dinuclear ruthenium complexes: structure and oxidative catalysis.
abstract: The synthesis of new dinuclear complexes of the general formula {[Ru(II)(trpy)]2(μ-pdz-dc)(μ-(L)}(+) [pdz-dc is the pyridazine-3,6-dicarboxylate dianion; trpy is 2,2':6',2″-terpyridine; L = Cl (1(+)) or OH (2(+))] is described. These complexes are characterized by the usual analytical and spectroscopic techniques and by X-ray diffraction analysis. Their redox properties are characterized by means of cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Complex 2(+) is used as the starting material to prepare the corresponding Ru-aqua complex {[Ru(II)(trpy)(H2O)]2(μ-pdz-dc)}(2+) (3(2+)), whose electrochemistry is also investigated by means of CV and DPV. Complex 3(2+) is able to catalytically and electrocatalytically oxidize water to dioxygen with moderate efficiencies. In sharp contrast, 3(2+) is a superb catalyst for the epoxidation of alkenes. For the particular case of cis-β-methylstyrene, the catalyst is capable of carrying out 1320 turnovers with a turnover frequency of 11.0 cycles min(-1), generating cis-β-methylstyrene oxide stereospecifically.
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), E-43007 Tarragona, Spain.
authors.forename: Carlo
authors.initials: C
authors.lastname: Di Giovanni
authors.forename: Lydia
authors.initials: L
authors.lastname: Vaquer
authors.forename: Xavier
authors.initials: X
authors.lastname: Sala
authors.forename: Jordi
authors.initials: J
authors.lastname: Benet-Buchholz
authors.forename: Antoni
authors.initials: A
authors.lastname: Llobet