The reduction of nitroarenes holds significant importance as it represents a critical transformation for the generation of arylamines, which are the primary intermediates in the synthesis of pharmaceuticals, agrochemicals, and dyes. A variety of halogenated nitroarenes have been selectively reduced with hydrazine hydrate in the presence of Pd/C in magnetized distilled water (MDW) to give the corresponding anilines. The advantages of this method are clean synthesis, environmentally benign, low costs, simple workup, and high reaction yields. In addition, the rate of reduction of 4-nitrophenol by hydrazine hydrate was investigated by monitoring changes in the absorption spectra of the reaction mixture in ordinary distilled water (ODW) and MDW by UV–visible spectroscopy methods.
Bakherad et al. (Sun,) studied this question.