Direct visualization of photo-induced disulfide through oxidative coupling of para-aminothiophenol

Chemical transformations under visible irradiation are interesting in green preparation. Herein, a photo-oxidative coupling reaction of para-aminothiophenol (p-ATP) dimerizing to 4-aminophenyl disulfide (APDS) rather than 4,4′-dimercaptoazobenzene (DMAB) was achieved in water by visible light irradiation, producing monodispersed organic nanoparticles in situ with strong light scattering visualized by the dark-field microscopy (DFM) imaging technique, owing to the formation of disulfide.