摘要:
                                Mono- and binuclear complexes of Ru(III) were synthesized using Schiff base ligands obtained by condensation of 2-pyridinecarboxaldehyde with 1,2- and 1,3- or 1,4-phenylenediamine, respectively. The complexes were characterized by analytical, spectral, conductance, cyclic voltammetry, and ESR studies. The epoxidation of alkenes was studied using these complexes as catalysts and iodosylbenzene as an oxidant. The complexes were found to be remarkably stable under the reaction conditions. Rates of the epoxidation of cis-cyclooctene using binuclear complexes were found to be nearly twice those using the mononuclear ones, indicating participation of both the metal centres of the former in the reaction. The absence of mu-oxo reaction product was shown by cyclic voltammetric studies. The mechanism of the reaction is suggested.