Substituent Effects on Rates of One-Electron Oxidation of Phenols by the Radicals ClO2, NO2, and SO3(1-)

Article abstract of DOI:10.1021/j100408a063

Rate constants for the reactions of ClO2, NO2, and SO3(1-) radicals with several substituted phenoxide ions have been measured by pulse radiolysis.They vary from the immeasurably slow (<10⁴) to almost diffusion-controlled rates (>10⁹ M^-1 s^-1) and depend on the redox potentials of the phenoxide ions and the inorganic radicals.With the weak oxidant SO3(1-) reverse reactions were observed in certain cases; i.e., the phenoxyl radical oxidizes sulfite ions.An attempt is made to correlate the rate constants with Hammett's substituent constants and the results are compared with those obtained previously for the reactions of various inorganic radicals with phenols and phenoxide ions.