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Oxidative cleavage of S‐arylmercaptoacetic acids by sodium perborate: Kinetic and correlation study
Author(s) -
Kabilan S.,
Pandiarajan K.,
Krishnasamy K.,
Sankar P.
Publication year - 1995
Publication title -
international journal of chemical kinetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.341
H-Index - 68
eISSN - 1097-4601
pISSN - 0538-8066
DOI - 10.1002/kin.550270504
Subject(s) - chemistry , thiophenol , steric effects , sodium perborate , intramolecular force , medicinal chemistry , substituent , protonation , kinetics , reaction rate constant , stereochemistry , organic chemistry , hydrogen peroxide , ion , physics , quantum mechanics
Kinetics 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 σ I and σ R ° values, the meta ‐compounds correlate well with σ I and σ R −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 σ I 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.