Ruthenium(III) complexes of the Schiff bases formed by the condensation of polymer bound aldehyde and the amines, such as 1,2-phenylenediamine (PS-opd), 2-aminophenol (PS-ap), and 2-aminobenzimidazole (PS-ab) have been prepared. The magnetic moment, EPR and electronic spectra suggest an octahedral structure for the complexes. The complexes of PS-opd, PS-ap, and PS-ab have been assigned the formula [PS-opcRuCl(3)(H2O)], [PS-apRuCl(2)(H2O)(2)], [PS-abRuCl(3)(H2O)(2)], respectively. These complexes catalyze oxidation of catechol using H2O2 selectively to o-benzoquinone. The catalytic activity of the complexes is in the order [PS-abRUCl(3)(H2O)(2)] > [PS-opdRuCl(3)(H2O)] > [PS-apRuCl(2)(H2O)(2)]Mechanism of the catalytic oxidation of catechol by ruthenium(III) complex is suggested to take place through the formation of a ruthenium(IT) complex and its subsequent oxidation by H2O2 to the ruthenium(IH) complex. (c) 2007 Wiley Periodicals, Inc.