PREPARATION AND PHOTOCHEMISTRY OF MACROMOLECULAR BOUND RUTHENIUM(II) COMPLEXES IN AQUEOUS-SOLUTIONS

Ruthenium(II) polypyridyl complexes with macromolecular ligands poly(methyl-olacrylamide-co-vinylpyridine) and poly(acrylamide-co-vinylpyridine) have been synthesized. The macromolecular ruthenium(II) complexes which are soluble in water have been characterized and their absorption and emission properties have been studied in aqueous solution. Photolysis of the complex in aqueous solution leads to photoaquation reactions with release of coordinated pyridines of the polymer. In the case of monomeric complex, cis-[Ru(bpy)2(py)2]Cl2, photolysis in water in presence of Cl- ions produces only the substitution of the pyridine by water whereas in the polymeric complexes, [Ru(bpy)2(MAAM-co-VP)2]Cl2 and [Ru(bpy)2(AM-co-VP)2]Cl2 photolysis in the presence of chloride produces [Ru(bpy)2(MAAM-co-VP)Cl]Cl and [Ru(bpy)2(AM-co-VP)Cl]Cl, respectively. Quantum yields for the photosubstitution reactions have been determined and mechanistic details are outlined.