Bis(iminato)ruthenates(III): Correlation of Half-wave Potential and Hydrolysis Constant with Electronic Effects of Substituent

Abstract

Influence of electronic effects of substituent on Schiff base ligands, derived from salicylaldehyde and 5-substituted salicylaldehydes with 2-aminophenole, on half-wave potential and hydrolysis constants of Sodium bis(iminato)ruthenates(III)hemitriethylamine solvate was investigated by cyclic voltammetry and electronic spectroscopy. New complex, Sodium bis[N-(2-oxy-κO-phenyl)salicylideneimine-κ2N,O(1-)]ruthenate(III) hemitriethylamine solvate was prepared and characterized on the basis of infrared and electron spectroscopy, MALDI-TOF/TOF mass spectrometry and ruthenium content. Cyclic voltammograms of complexes in organic solvents demonstrate quasi-reversible one-electron process with pronounced reducing power of Ru(II). Appling Hammet equation for half-wave potential of complexes we found that substituents conduct electronic density via X-C6H3-O-Ru-O-C6H3-X bonds. Electron spectroscopy was used to investigate behavior of complexes under physiological conditions and showed that hydrolysis occur. Constants of hydrolysis were determined spectrophotometrically using kinetics of pseudo-first order.