Highly chemoselective hydrogenation of nitroarenes catalyzed by 3,6-di(pyridin-2-yl)-1,2,4,5-s-tetrazine capped‑silver nanoparticles in aqueous medium at room temperature

Abstract

3,6-Di(pyridin-2-yl)-1,2,4,5-s-tetrazine capped‑silver nanoparticles (TzAgNPs) exhibit an excellent catalytic activity and chemoselectivity for the reduction of various substituted nitroarenes to the corresponding aromatic amines in aqueous medium with sodium borohydride and hydrazine hydrate as a hydrogen donor at room temperature. The reaction kinetics of the reduction of 4-nitrophenol to 4-aminophenol has also been studied to determine the apparent rate constant. The catalyst TzAgNPs efficiently reduces the nitro group under very mild conditions, thus affording excellent yields within very short reaction time (˂20 min), and shows high selectivity even in the presence of other sensitive functional groups.