الفهرس 
Oxidation of organic substratesOnly 14 pages are availabe for public view
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Abstract
The present work included the use of peroxydisulphate ion (s20s2-) for the oxidation of p-nitrodiphenylamine (p-N02-DPA), p-aminodiphenylamine (p- NH2 - DPA) benzeneazodiphenylamine (BADPA), and p-aminoazobenzene (p-NH2-AZB). The oxidation reactions were carried out in alcoholic aqueous solution either in the absence or in the presence of A~’io n as catalyst, and the reaction rates were measured spectrophotometrically. This catalyst ion showed a considerable enhancement in reaction rates. In the case of uncatalyzed oxidation, the substrate / ~20in~ter~act-ion s were generally slow (except for the p- NH2-DPA) and followed second order kinetics, first order for each individual reacting species. For the catalyzed oxidation, the situation varied from one substrate to another. For p-N02-DPA the rate was first order dependent on the concentration of the substrate, oxidant, and the catalyst ion, particularly at moderate concentration of Ag+. At high concentration of the catalyst, it was independent of the substrate concentration and exclusively affected by those of the catalyst and oxidant ions. With p-NH2-DPA the reaction was rather fast so that it was followed by the stopped-flow spectrophotometer and thus no Agf was added. The fast oxidation process yielded a fairly stable wine red intermediate product, which underwent a slow decay upon further oxidation with the s20s2- . The overall rate for the formation and the decay reactions obeyed second order kinetics, being first order for each reactant. In the case of benzeneazodiphenylamine the catalyzed rate was independent of the substrate concentration.