RuII Complexes of Bis(1,10-phenanthrolin-2-yl)diazines

A series of three bis-tridentate bridging ligands has been prepared in which two 1,10-phenanthroline units have been symmetrically appended to a central pyridazine, pyrimidine, or pyrazine ring. These ligands have been treated with [Ru(tpy-d(11))Cl-3] to afford both mono- and dinuclear complexes whose photo- and electrochemical properties have been evaluated (tpy = 2,2':6',2"-terpyridine). A structural comparison is made between [(tpy)Ru(3)Ru(tpy)](PF6)(4) and a previously reported complex involving 2,2'-bipyridines in place of phenanthrolines on the bridging ligand and surprisingly little difference is found. (C) Wiley-VCH Verlag GmbH Co.