Catalytic effects of cationic nanoparticle (CTABr/NaX/H2O, X = Cl, Br) for the piperidinolysis of phenyl salicylate ions

Resumo

The expression of pseudo-second-order rate constants (k_X) for cationic nanoparticle (CN) [CTABr/NaX/H₂O, X = Br, Cl, CTABr = cetyltrimethylammonium bromide] catalyzed piperidinolysis-ionized phenyl salicylate (PSa^–), at constant [CTABr]_T, 0.1 M piperidine (Pip), and 35°C, were calculated from the relationship: k_obs = (k₀ + k_X[NaX])/(1 + K^X/S[NaX]), in which k₀, k_X, and K^X/S are constant kinetic parameters and k_obs represents the pseudo-first-order rate constant for Pip reaction with phenyl salicylate ion in the presence of CN. The source of the large catalytic effect of CN catalyst was shown to be due to the transfer of PSa^– from pseudo-phase of the CNs to the bulk aqueous phase through X^–/PSa^– ion exchange at the surface of the CNs.