Internal reflectance spectra associated with staircase voltammetry in anodic oxidation of aromatic amines in acetonitrile

Dynamic transformation profiles of internal reflectance spectra were observed for anodic oxidation of triphenylamine, N-methyldiphenylamine, and N,N-dimethyl-aniline in acetonitrile. Absorption bands appearing in these spectra are compared with those in conventional absorption spectra of the electrolyzed aromatic amine solutions by controlled-potential electrolysis. From this comparison, the internal reflectance bands are assigned to a tetraphenylbenzidine radical monocation and dication, a dimethyl-diphenylbenzidine radical monocation and dication, etc.