KINETICS OF THE OXIDATION OF METHYL PHENYL SULFIDE BY HYDROGEN PEROXIDE IN THE PRESENCE OF HYDROCARBONATE ANION

摘要

The oxidation of methyl phenyl sulfide in water and water-alcohol mixtures takes place both by a noncatalytic mechanism and with the participation of hydrogen peroxide as catalyst;in the presence of ammonium hydrocarbonate it takes place by a mechanism involving HCO_4~-as a more active oxidant than hydrogen peroxide(>100 times).In water-alcohol media(ethylene glycol,isopropyl alcohol,tert-butanol)the rate decreases in the order H_2O > EG > 1PA > TEA.The reactivity of organic sulfides varies in the following way:MeSPh=EtSPh Et_2S.The results were interpreted from the standpoint of a molecular mechanism of oxidation of the sulfide with H_2O_ 2and HCO_4~-through a polar transition state,containing the HOX molecule(X=H,OH,OR)as acid-base catalyst.