Photochemical, radiolytic, and thermal oxidation of 4-dimethylamino-2′,4′-dinitroazobenzene—model experiments for the degradation of azo dyes

4-Dimethylamino-2′,4′-dinitroazobenzene (1) undergoes photo-oxidation in propan-2-ol giving 4-dimethylamino-2′,4′-dinitro-NNO-azoxybenzene (2) and other products; (2) is also formed by γ-radiolysis in presence of oxygen and by thermal reaction with hydrogen peroxide in the same solvent.