Kinetics and mechanism of nanoparticles (CTABr/MX/H2O)-catalyzed piperidinolysis of ionized phenyl salicylate. 1

Kinetics and Mechanism of Alkaline Hydrolysis of N-(o-Aminophenyl)Phthalimide in the Presence and Absence of Cationic Micelles and Sodium Salts of Aliphatic Acids

Pseudo first-order rate constants, k obs, for the alkaline hydrolysis of N-( o-aminophenyl) phthalimide, obtained at constant [CTABr]T (total concentration of cetyltrimethylammonium bromide) and varying concentrations of inert salt MX (MX = sodium formate, sodium acetate, sodium propanoate, sodium butyrate, sodium valerate and sodium hexanoate) follow the relationship: [Formula: see text], where θ and KX/S are empirical constants and S = HO-. The values of KX/S for each aliphatic acid decrease with an increase in [CTABr]T. This relationship gives an empirical constant whose magnitude is the measure of the ability of an ion, X-, to expel another counterion S-, from the cationic micellar surface to the bulk aqueous phase. The values of the empirical constant, KX/S, are used to derive the ion exchange constant, KBrX.

Study of Cationic and Nonionic Mixed Micelles with NaBr and 3,5-Cl2C6H3CO2Na by Use of Probe Nucleophilic Reaction of Piperidine with Ionized Phenyl Salicylate

Behaviors of cationic and nonionic mixed micelles in the form of hexadecyltrimethylammonium bromide (HDABr) and hexadecyltrimethylammonium bromide-Polyethylene glycol hexadecyl ether (C₁₆E₂₀), in the presence of inert salts (NaBr and 3,5-dichlorosodium benzoate), by the use of reaction probe between Pp and ionized PhSH (Pp = piperidine and PhSH = phenyl salicylate), has been reported in this work. The values of R_X^Br (R_X^Br denotes ion exchange constants obtained in the presence of micelles of different structural features) or K_X^Br (K_X^Br denotes ion exchange constants obtained in the presence of micelles of the same structural features) for 3,5-Cl₂C₆H₃CO₂^- were almost the same at three different [HDABr]_T (0.006, 0.010 and 0.015 M). The average value of R_X^Br or K_X^Br determined, in the presence of pure HDABr micelles, using semi empirical kinetic (SEK) method appeared to be almost 2½-fold larger (R_X^Br or K_X^Br = 198) than that in the presence of mixed HDABr-C₁₆E₂₀ micelles (R_X^Br or K_X^Br = 78). Rheological measurements indicated the existence of wormlike/twisted micelles and vesicle at 0.015 M pure HDABr, various [3,5-Cl₂C₆H₃CO₂Na], and 25 and 35℃ whereas there were evidence of only spherical micelles in the presence of mixed HDABr-C₁₆E₂₀ ([HDABr]_T = 0.015 M and [C₁₆E₂₀]_T = 0.006 M) at both temperatures.