Photoinduced hydrogen evolution with viologen-linked ruthenium(II) complexes and hydrogenase

Viologen-linked ruthenium(II) complexes with different methylene chain leng th between ruthenium complex and viologen, Ru(bpy)(2)(dcbpy)CnVCH3 (n = 2-3 ), were synthesized and characterized by using spectroscopic techniques. Fr om luminescence spectra, the photoexcited state of Ru(bpy)(2)(dcbpy) is oxi datively quenched by binding viologen, and an intramolecular electron trans fer occurs. Ru(bpy)(2)(dcbpy)CnVCH3 were applied for the photoinduced hydro gen evolution in the system containing nicotinamide-adenine dinucleotide ph osphate (reduced form, NADPH), Ru(bpy)(2)(dcbpy)CnVCH3 and hydrogenase unde r steady state irradiation. (C) 1999 Elsevier Science B.V. All rights reser ved.