A kinetic study of the electron-transfer in the reaction of tribenzylchlorotin with [CoW12O40]5-

A kinetic study of the electron-transfer in the reaction of tribenzylchlorotin with potassium 12-tungsto cobalt (III) ate ion, K-5[CoW12O40], abbreviated. as Co(III)W, has been performed in different solvents. The studies were carried out in methanol, ethanol, acetonitrile and acetic acid/water. The rate constants, reaction rates and activation parameters were calculated. Our findings show that the rate of disappearance. of the Co(III) is pseudo-first order. The kinetic data is strongly affected by used solvents. The maximum and minimum rate constants were achieved in the ethanol and acetic acid/water (70/30) as a solvent, respectively. In all of the used solvents, negative value of activation entropies was observed, but negative activation enthalpies are observed in methanol, ethanol and acetonitrile. The reaction rate is increased with increase of Co(III) concentration. (C) 2009 Fatemeh F. Bamoharram. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.