Synthesis,Photophysical, and Electrochemical Properties of Ruthenium(II) Polypyridyl Complexes containing Open‐Chain Crown Ether

Four polypyridyl bridging ligands BL^1?4 containing open‐chain crown ether, where BL^1?3 formed by the condensation of 4,5‐diazafluoren‐9‐oxime with diethylene glycol di‐p‐tosylate, triethylene glycol di‐p‐tosylate, and tetraethylene glycol di‐p‐tosylate, respectively. BL⁴ formed by the reaction of 4‐(1,10‐phenanthrolin‐5‐ylimino)methylphenol with triethylene glycol di‐p‐tosylate, have been synthesized. Reaction of Ru(bpy)₂Cl₂·2H₂O with BL, respectively, afforded four bimetallic complexes (bpy)₂RuBL^1?4Ru(bpy)₂]⁴⁺ as PF₆]^? salts. Electrochemistry of these complexes is consistent with one Ru^II‐based oxidation and several ligand‐based reductions. These complexes show metal‐to‐ligand charge transfer absorption at 439‐452 nm and emission at 570‐597 nm.