Kinetics of monochelation of aqueous chromium(III) by methyl 2-oxocyclopentanecarboxylate

Abstract

From a study of the complexation of methyl 2-oxocyclopentanecarboxylate with Cr(III) in aqueous solution, thermodynamic and kinetic parameters were obtained. The equilibrium constant of the monocomplex was determined spectrophotometrically. The kinetic processes of monochelation were investigated spectrophotometrically in aqueous solution at 50°C and ionic strength 0.5 mol dm À3 NaClO 4 . The mechanism proposed to account for the kinetic data involves a double reversible pathway where both Cr 3 and Cr(OH) 2 react with the enol tautomer of the ligand. Some comparative analyses with the homologous 2-acetylcyclopentanonechromium(III) were made.