View article

A series of mononuclear ruthenium polypyridyl complexes [Ru(Mebimpy)(pic)₃](PF₆)₂ (2; Mebimpy=2,6‐bis(1‐methylbenzimidazol‐2‐yl)pyridine; pic=4‐picoline), Ru(bimpy)(pic)₃ (3; H₂bimpy=2,6‐bis(benzimidazol‐2‐yl)pyridine), trans‐[Ru(terpy)(pic)₂Cl](PF₆) (4; terpy=2,2′;6′,2“‐terpyridine), and trans‐[Ru(terpy)(pic)₂(OH₂)](ClO₄)₂ (5) are synthesized and characterized as analogues of the known Ru complex, [Ru(terpy)(pic)₃](PF₆)₂ (1). The effect of the ligands on electronic and catalytic properties is studied and discussed. The negatively charged ligand, bimpy²⁻, has a remarkable influence on the electrochemical events due to its strong electron‐donating ability. The performance in light‐ and Ce^IV‐driven (Ce^IV=Ce(NH₄)₂(NO₃)₆) water oxidation is successfully demonstrated. We propose that ligand exchange between pic and H₂O occurs to form the real catalyst, a Ru–aqua complex. The synthesis and …