Oxidation of malononitrile complex of pentaammineruthenium(II)

The oxidation of Ru(NH3)5NCCH2CN2+ complex by the peroxydisulfate ion in the aqueous solution yields two products, Ru(NH3)5NHCOCH2CN2+ with λmax = 373 nm and with λmax = 863 nm. The distribution of the products depends on the acidity of the solution with the formation of the binuclear complex favored at lower acid concentrations. A mechanism for the oxidation has been proposed by the kinetic studies in the region of 0.001-0.10 M acid concentrations.