Electron spin resonance studies of radicals and radical-ions in solution. Part IV. Further intermediates in the reduction of aromatic nitro- and nitroso-compounds
The oxidation and reduction of nitrosobenzene, phenylhydroxylamine, and some of their derivatives have been studied by electron spin resonance methods in a variety of solvents. From the observed spectra the species PhNO– and PhṄHO have been identified. PhNO– is observed only in strongly alkaline solution and in the immediate vicinity of the cathode during the electrolytic reduction of nitrosobenzene. In neutral or acid solution PhNO–is replaced by PhNHO which is identical with the first oxidation product of phenylhydroxylamine. The role of these paramagnetic species in the reduction of aromatic nitro-compounds is discussed briefly.