Kinetics and Mechanism of Nanoparticles-Catalyzed Piperidinolysis of Anionic Phenyl Salicylate

Abstract EN

The values of the relative counterion ( X ) binding constant R X Br (= K X / K Br , where K X and K Br represent cetyltrimethylammonium bromide, CTABr, micellar binding constants of X v - (in non-spherical micelles), v = 1,2 , and Br− (in spherical micelles)) are 58, 68, 127, and 125 for X v − = 1 − , 1 2 − , 2 − , and 2 2 - , respectively.

The values of 15 mM CTABr/[ Na v X ] nanoparticles-catalyzed apparent second-order rate constants for piperidinolysis of ionized phenyl salicylate at 35°C are 0.417, 0.488, 0.926, and 0.891 M−1 s−1 for Na v X = Na1, Na2 1, Na2, and Na2 2, respectively.

Almost entire catalytic effect of nanoparticles catalyst is due to the ability of nonreactive counterions, X v - , to expel reactive counterions, 3 −, from nanoparticles to the bulk water phase.