Oxidative cleavage of S-arylmercaptoacetic acids by sodium perborate: Kinetic and correlation study
作者:S. Kabilan、K. Pandiarajan、K. Krishnasamy、P. Sankar
DOI:10.1002/kin.550270504
日期:1995.5
AbstractKinetics of oxidation of twenty six S‐arylmercaptoacetic acids (SAMA) (I) by sodium perborate (PB) have been studied in acid medium. The product of oxidation is the corresponding thiophenol. The rate data of meta‐and para‐substituted acids have been correlated with DSP equations. While the para‐compounds correlate well with σI and σR° values, the meta‐compounds correlate well with σI and σ values. The reaction constants are negative and of smaller magnitudes. Further, the ortho‐substituted acids show a good correlation with a triparametric equation involving Taft's σI and R° and Charton's steric parameter ν. There is a considerable steric contribution to the total ortho‐substituent effect. Based on these observations, mechanism involving the formation of protonated arylsulfinylacetic acid intermediate, followed by an intramolecular rearrangement leading to the product thiophenol has been proposed. © 1995 John Wiley & Sons, Inc.