Studies on Kinetics of Hydroxylation of p-Rosaniline Hydro-chloride by Sodium Hydroxide in Micellar Environment

摘要

Basic hydrolysis of p-rosaniline hydrochloride in presence of solution of anionic surfactant, e.g., sodium dodecyl sulphate (SDS), cationic surfactant, e.g., hexadecyl trimethyl ammonium bromide (C_16TABr) and nonionic surfactant, e.g., triton X-100 has been studied. C_16TABr is known to increase the rate of reaction of triphenyl methyl carbonium ions with the hydroxide ion, where as the anionic micelles of SDS and non-ionic of TX-100 inhibit this rate. At lower concentration of NaOH, reaction rate increase rapidly with cationic surfactant concentration and with indreasing hydroxide ion concentration, an inhibition effect is obsrved for all surfactant concentrations studied. The addtion of monohydric alcohol, viz., ethanol, n-propanol, n-butanol and solvent like acetone and ethylene glycol decreases the cationic micellar catalysed rate of carbinol formation and on the other hand increase the anionic micellar inhibited rate. The effectiveness of these solvents in reducing the extent of overall inhibition by sodium dodecyl sulphate has been found to folow the order: ethylene glycol < n-propanol