Kinetic Study of the Hydrolysis of p-Propoxy Aniline Phosphate Triester

Kinetic study of the hydrolysis of p-propoxy aniline phosphate triester has been done in 1.0 to 6.0 mol dm3 HCl and pH 1.24 to 7.46 at 97 0.5oC in aqueous dioxin (v/v) mixture. The rate of hydrolysis was determined by measuring the rate of appearance of inorganic phosphate by Allens modified colorimetric method [1]. The concentration of triester in all the kinetic runs was maintained 5.0104 mol. cm3. The first order rate coefficients have been calculated using integrated form of the corresponding rate equation Effects of variable factors such as temperature, pH, ionic-strength, concentrations etc. on the rate of hydrolysis of the triester have been studied to find out the participation of water molecule. Concepts such as Hammett acidity function [2]. Bunnett parameters [3]. Zucker-Hammett hypothesis [4] and Bunnett-Olsen plot [5] together with Arrhenius parameters [6], comparative isokinetic data and isokinetic relationship [78] of other triesters of known mechanism were considered for deciding the molecularity, bondfission and probable mechanism. The ppropoxy aniline phosphate triester has been found to be reactive via conjugate acid and neutral species but for the sake of convenience results for only conjugate acid species have been described and discussed in this study.