Structure, chemical and photochemical reactivity and biological activity of some ruthenium amine nitrosyl complexes

摘要

Through spectroscopic (X-ray, Infrared, ~1H-NMR, EPR, UV-vis) and electrochemical (cyclic voltammetry, differential pulse polarography) data and quantum mechanical calculations, the formulation [Ru(II)NO+] was attributed to a series of new ruthenium(Ⅱ) amine compounds. A remarkable stability of the Ru(Ⅱ) relative to Ru(Ⅲ) was observed upon coordination to NO. The presence of nitrosyl in the coordination sphere results in dramatic implications in the lability, acidity and redox properties of the ligand trans to NO. These effects are higher than expected just on the basis of one unity increment in the metal center charge. Based on molecular orbital (MO) analysis and on reduction product analysis, the site of the reduction [Ru(NO)]~(3+) +e~-→[Ru(NO)]~(2+) was assigned to the NO ligand.