Oxidation of substituted phenethyl alcohols by sodium N-chlorobenzenesulphonamide: A kinetic study

The kinetics of the oxidation of six substituted phenethyl alcohols by sodium N-chlorobenzenesulphonamide or chloramine-B (CAB) in the presence of HCl was studied at 35 degrees C. The rate shows a first-order dependence on CAB](0) and H+] and is fractional order in PEA](0) and Cl-]. Ionic strength variations, addition of reaction product of benzenesulphonamide and variation of the dielectric constant of the medium have no effect on the rate. The solvent isotope effect k(1)H(2)O/k(1)D(2)O approximate to 0.78. Proton inventory studies were made in H2O-D2O mixtures, The rates correlate satisfactorily with the Hammett linear free energy relationship. The reaction constant rho was -3.5 for electron-releasing and -0.30 for electron-withdrawing groups at 35 degrees C. Activation parameters Delta H*, Delta S*, Delta G* and log A were calculated for the reaction, An isokinetic relationship is observed with beta = 338 K, indicating enthalpy as a controlling factor