A New Method for the Synthesis of Dinitrogen Tetroxide Impregnated On Charcoal (N2O4/Charcoal) and It's Application as Selective Oxidant of Thiols to Disulfides Organic Compounds

Abstract

Abstract A new laboratory method was investigated to prepare a liquid dinitrogen tetroxide (purity, 99%) from nitric acid and Al-Zahdi date. N2O4 was easily impregnated on charcoal to give a stable homogeneous reagent N2O4 / charcoal. A fast and efficient method for the chemoselective oxidative coupling of heterocyclic thiols to afford their corresponding heterocyclic disulfides using liquid dinitrogen tetroxide (N2O4) as the reagent in CH2Cl2 at room temperature is described. The stability, easy preparation, high selectivity of the reagent and high percent of products make this method as a useful procedure. The purity of liquid N2O4 was determined by titration method. The chemical structure and purity of the disulfide products were proved by using melting point measurement, elemental analysis, and FTIR spectroscopy.