Synthesis and properties of conjugated bimetallic ruthenium complexes with σ,σ-bridging azobenzene chains

A versatile synthetic route to conjugated bimetallic ruthenium complexes with σ,σ-bridging azobenzene chains was developed, and new ruthenium complexes with various ligands were synthesized and characterized. These bimetallic complexes showed a remarkable absorption in the visible region (λmax: 452–483 nm), and undergo trans-to-cis isomerization under UV light irradiation for short time. Electrochemical study showed that the metal centers in bimetallic complexes containing the CHdouble bond; length as m-dashCHsingle bondC6H4Ndouble bond; length as m-dashNC6H4single bondCHdouble bond; length as m-dashCH bridge interact with each other.