title: Spectro- and electrochemical studies of some ruthenium and osmium complexes of 2-(2'-pyridyl)benzimidazole; complexes with intra-molecular charge transfer.
abstract: Reaction of Ru3(CO)12, with 2-(2'-pyridyl)benzimidazole (HPBI) resulted in the formation of Ru(CO)3(HPBI) (I) complex. In presence of pyridine or dipyridine, the two derivatives [Ru(CO)3(HPBI)].Py (II) and [Ru(CO)3(HPBI)].dpy (III) were isolated. The corresponding reactions of Os3(CO)12 yielded only one single product; Os(CO)2(HPBI)2 (IV). Spectroscopic studies of these complexes revealed intramolecular metal to ligand CT interactions. Reactions of RuCl3 with HPBI gave three distinct products; [Ru(HPBI)2Cl2]Cl (V), [Ru(HPBI)(dipy)Cl2]C1 (VI) and [Ru(PBI)2(py)2]Cl (VII). The UV-vis studies indicated the presence of intramolecular ligand to metal CT interactions. Electrochemical investigation of the complexes showed some irreversible, reversible and quasi-reversible redox reactions due to tautomeric interconversions through electron transfer.
authors.affiliation: Chemistry Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
authors.forename: M M
authors.initials: MM
authors.lastname: Khalil
authors.forename: S A
authors.initials: SA
authors.lastname: Ali
authors.forename: R M
authors.initials: RM
authors.lastname: Ramadan
mesh_terms: D001562:Benzimidazoles / Q000737:chemistry*; D004563:Electrochemistry; D008956:Models, Chemical; D015394:Molecular Structure; D009992:Osmium / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*; D013053:Spectrophotometry
chemical_list: D001562:Benzimidazoles; D009992:Osmium; D012428:Ruthenium