Effect of cetyltrimethylammonium bromide on the oxidation of β-alanine by N-bromophthalimide in acidic medium

The kinetics of the oxidation of p-alanine (Ala) by N-bromophthalimide (NBP) has been studied in the presence of cationic surfactant, cetyltrimethylammonium bromide (CTAB) at 313 K. The oxidation kinetics exhibits first order kinetics with respect to [Oxidant], fractional order of [Ala] and inverse fractional order of [H+] on the rate of reaction. The rate of reaction decreases with decreasing dielectric constant of the medium. The rate constant increases with increasing CTAB and then constant. Increasing [Hg(OAC)(2)] and inorganic salts i.e. [Cl-] and [Br-] increased the rate of reaction, whereas a change in ionic strength of the medium had no effect on oxidation velocity. Methyl Cyanide as the main oxidation product has been identified. Thermodynamic and activation parameters have been evaluated. The rate constants, binding constants with surfactant (CTAB) and the index of cooperativity have also been evaluated.