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Nucleophilicity of functional surface active substances in the transfer of phosphoryl groups

“…1, a and b). The kinetic behaviour of the decomposition of organophosphorus compounds in micelles of IV is analogous to that established previously for compounds I-III [3][4][5][6]. The nucleophilic center, as in the case of the methyl analog IVa, is the oxygen atom of the oxime group (scheme (3)).…”

The effect of the nature of the head group on the micellar effects of functional/cationic co-micelles in acyl transfer reactions

“…(5) the constant for the bonding of the hydroxide ion was assumed to be equal to~40 L/mol [15], and its reactivity in the micellar pseudophase was taken as equal to that in water. In spite of the adopted assumptions the simple pseudophase model successfully describes the whole series of bimolecular reactions [1,8], and no substantial difference between the rate constants in water and in the micelle is observed here for the reactions involving the anionic nucleophiles [2,[4][5][6][7]. The second-order rate constants in the micellar pseudophase depend on the tentative values of V m used to calculate the local concentration of the reagents.…”

“…II III I diethylphosphonic (NPDEPN), and toluenesulfonic (NPTS) acids [5][6][7], while the observed micellar effects can be described in terms of a simple pseudophase model [8].…”

“…(5) corresponds to the reaction involving the functional SFA in the micellar pseudophase, while the second term corresponds to the reaction of the hydroxide ion with the substrate in the mixed micelle. The given reaction in the absence of the inert SFA is characterized by the dependence of the observed rate constant k ob on C 0 , which with the functional SFA at a concentration above the CMC has the form of a curve with saturation [5][6][7], and the concentration of the SFA at which the limiting value of the observed pseudofirst-order rate constant is observed (k ob = k ob max = k m = k 2 m /V m ) is determined exclusively by the distribution coefficient of the substrate. The concentration of the nucleophilic fragments in the micelle remains unchanged and the highest possible in the whole range of SFA concentrations.…”

“…[2,8]. For the investigated system we used the value V m = 0.5 L/mol, proposed earlier for metal micelles [12] and the micelles of functional SFAs I-III [5][6][7]. By virtue of the structural similarity of the head groups of the functional (I-III) and inert (CMIC) SFAs the molar volume of their co-micelles (V m ) can also be taken as equal to 0.5 L/mol.…”