Synthesis, characterization, luminescent and redox properties of some mononuclear and dinuclear ruthenium(II) polypyridyl complexes

Abstract

A series of mononuclear and dinuclear Ru(II) complexes of the type [RuL(X)2]n+ and [Ru2L′(X)4]n+, L=L1H, n = 1; L=L+ n=2; L′=L3H2, n=2; L′=L4, n =4 and X=2,2′- bipyridyl as well as 1,10-phenanthroline, have been prepared and characterized by IR, 1H-NMR UV-vis spectra, FAB Mass and elemental analysis data. The complexes display metal-ligand charge-transfer (MLCT) transitions in the visible region and show hyperchromic shift upon addition of DNA solution. Emission observed in the range 580-595 nm is quenched upto 7.3-40.5% upon addition of buffered solution of calf thymus DNA. Acetonitrile solution of the complexes show electrochemical oxidation of the ligands.