Metal-metal interactions in dinuclear ruthenium complexes containing bridging 4,5-di(2-pyridyl)imidazolates and related ligands.

The dinuclear bis(2,2'-bipyridine)ruthenium complex of 4,5-di(2-pyridyl)imidazolate has been prepared and separated into its (meso and rac) diastereoisomers. The 2-phenyl substituted analogue forms the meso isomer selectively. All three complexes have been characterised by 1H NMR and X-ray crystallography. Electrochemical measurements and spectroelectrochemistry of the mixed-valence states reveal strong metal-metal interactions and IVCT bands that are highly dependent on the electrolyte.