Mechanism of micellar effects on acylation of aryl oximes by p-nitrophenyl carboxylates

Effect of Surfactants and Temperature on Adsorption Behavior of Metal Ions on Organic–Inorganic Hybrid Exchanger, Acrylamide Aluminum Tungstate

“…In the PIE model, counter-ion selectivity is expressed as an ion exchange constant [18]. The PIE model has been extended to cover the reactions of ions and charged micelles [19]. The adsorption mechanism of metal ions on the ion exchange materials in the presence of surfactants (cationic or anionic) can be explained on the basis of micellar association which can be explained in terms of the electrostatic model, i.e., Guoy-Chapman electrical double layer approximations [20,21] and the counter ion binding approximation [22].…”

Binding Energy, Specificity, and Enzymic Catalysis: The Circe Effect

“…136) are increased by factors of (220). The system was examined quantitatively by measuring the partitioning of the reactants between the aqueous medium and the micelle and determining the effect of the micelle on the ionization of the bound oxime to the reactive anionic species.…”

“…It is of interest that if the chain length of the acyl portion of the ester is increased, from acetate to heptanoate, there is a progressive decrease in the calculated second-order rate constant for the reaction in the micellar phase (220). T h e observed maximum rate increase relative to the reaction in water is the same for the acetate and heptanoate esters, but the partitioning of the heptanoate ester into the micelle is more favorable, so that the calculated rate constant in the micelle is decreased 30-fold.…”

Micellar effects on the reactions of 2,4-dinitrophenyl phosphate and ethyl p-nitrophenyl phosphate with amines

“…Despite the problems in separating the various factors which could affect values of ko and k~ both in the presence and absence of micelles it is evident that the structure of the organic residue of the amine is of key importance in the micellar reaction (Table VI), although our evidence does not distinguish between effects due to partitioning of the amine between water and the micelle and to reactivity differences in the micelle, although the partitioning cannot be the sole cause of the variations of k&o which decreases with increasing length of the nalkyl group above (28 (Table VI). In addition the rate constants for amine attack in the micelles will depend upon the hydrophobicity of the alkyl group, which will determine the extent to which the amino group is brought into the Stern layer of the micelle close to the aryl group of the substrate.…”