Electron transfer reactions of 2,2′-thiodiethanoic acid in aqueous solutions: a pulse radiolysis study
Abstract
OH radicals are observed to react with 2,2′-thiodiethanoic acid in aqueous solutions containing a high concentration of HClO4 by an inner-sphere electron transfer reaction mechanism to form solute dimer (λmax= 520 nm) radical cations at high solute concentrations. The stability constant for the dimer radical cation has been determined to be 68 dm3 mol–1 at 25 °C. The decay kinetics of solute dimer radical cation is discussed in detail and deprotonation of the solute radical cation is found to be the rate-determining step. The solute dimer radical cations are able to undergo electron transfer reactions with Br– and form a transient band (λmax= 385 nm) which is assigned to a bromine–solute adduct.