22865-56-1Relevant articles and documents
Kinetics and mechanism of oxygenation of aromatic sulfides and arylmercaptoacetic acids by peroxomonophosphoric acid
Thenraja, Duraisamy,Subramaniam, Perumal,Srinivasan, Chockalingam
, p. 4283 - 4290 (2002)
The oxygenation of aryl methyl sulfides and diaryl sulfides by peroxomonophosphoric acid in acetonitrile-water mixture follows an overall second-order kinetics, first-order in each reactant. The study of the influence of [H+] on the oxidation of phenyl methyl and diphenyl sulfides reveals that H2PO5- and HPO52- are the oxidising species in the oxidation process. In substituted phenyl methyl sulfides and diphenyl sulfides, the rate of oxygenation is accelerated by electron-donating substituents and retarded by electron-withdrawing groups, indicating the nucleophilic displacement by the sulfide sulfur on the peroxide oxygen. The negative ρ value obtained in the correlation analysis of rate constants with σ constants also shows the formation of a more positively charged sulfur species in the rate-limiting step. Studies with different alkyl phenyl sulfides (C6H5SR; R=Me, Et, Pri or But) indicate that the rate is retarded by bulky R groups. Similar kinetic results are also obtained in the peroxomonophosphoric acid oxidation of sodium phenylmercaptoacetate. On the basis of the kinetic studies, a common mechanism has been proposed.