A new family of Ru complexes for water oxidation.
Reaction of the bridging ligand 3,6-bis-[6'-(1' ',8' '-naphthyrid-2' '-yl)-pyrid-2'-yl]pyridazine (1) with [Ru(DMSO)4Cl2] in aqueous ethanol followed by excess 4-substituted pyridine (4-R-py) in the presence of triethylamine provides a series of three well-organized dinuclear complexes characterized by 1H NMR, MS, and X-ray. Mononuclear analogues are prepared from 4-tert-butyl-2,6-di(1',8'-naphthyrid-2'-yl)pyridine (5) and characterized in a similar fashion. All six complexes show electronic absorption and redox properties consistent with the electron donor/acceptor ability of the axial 4-R-py ligand. When an acetonitrile solution of the catalyst is added to an aqueous Ce(IV)-CF3SO3H solution (pH = 1.0) at 24 degrees C, oxygen evolution is observed for both mono and dinuclear systems. Turnover numbers range from 50 to 3200 with the best results being found when the axial ligand is 4-methylpyridine (mononuclear TN = 580 and dinuclear TN = 3200).
Zong
Ruifa
R
Department of Chemistry, 136 Fleming Building, University of Houston, Houston, Texas 77204-5003, USA.
Thummel
Randolph P
RP
D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D010084:Oxidation-Reduction; D012428:Ruthenium / Q000737:chemistry*; D014867:Water / Q000737:chemistry
D009942:Organometallic Compounds; D014867:Water; D012428:Ruthenium