Polarographic study of analytically important indophenol derivatives

Abstract

Six indophenols, with redox and acid—base indicator properties, have been examined by polarographic and related electrochemical techniques. All indophenols displayed a single reduction wave, due to the uptake of two electrons and two photons. Half-wave potentials and the acid—base dissociation constants have been determined. The post-waves displayed by halogenated indophenols and the pre-wave of 2,3', 6-trichloroindophenol have been examined and explanations for their occurrence are suggested.