Electron transfer from indoles, phenol, and sulfite (SO32-) to chlorine dioxide (ClO2.)

Abstract

With the ClO/sub 2//ClO/sub 2//sup -/ couple as reference the one-electron-reduction potentials have been determined for four methylated indolyl radical cations. Their E/sup 0/ values are 1.23 V (N-Me), 1.10 V (2-Me), 1.07 V (3-Me), and 0.93 V (2,3-diMe). E/sup 0/ values were also measured for the following: tryptophylH/sup .+//trypH 1.24 V, SO/sub 3//sup .-//SO/sub 3//sup 2 -/ 0.76 V, and phenoxy/sup .//phenolate 0.80 V. The redox potentials were obtained from purely kinetic data (for tryptophan and 2-,3-, and N-methylindole) or from combined kinetic and thermodynamic measurements.