The first example of photochemical reduction of nitrite into nitrogen monoxide by a dinuclear Ru(II)-Cu(II) complex and photoinduced intramolecular electron transfer reaction between Ru(II) and Cu(II) moieties

The photochemical reduction of nitrite to NO by the dinuclear Ru(II)-Cu(II) complex ([Ru(bpy)(2)(Mebpy-COOC3H6)Me(2)bpaCu(H2O)(ClO4)](ClO4)center dot(PF6)(2)center dot(H2O) was observed in the absence of sacrificial electron donor reagents in CH2Cl2. The reaction rate of the photoreduction of nitrite depended upon the concentration of the excited Ru(II) moiety in the complex. The photoinduced intramolecular electron transfer rate constants between the Ru(II) and Cu(II) moieties (*Ru(II)-Cu(II) -> Ru(III)-Cu(I) and Ru(III)-Cu(I) -> Ru(II)-Cu(II)) in the dinuclear complex were calculated to be 2.3 x 10(9) and 8.3 x 10(7) s(-1), respectively, by laser flash photolysis.