The factors determining the micellar effects on nucleophilic substitution reactions

Zakharova, L. Ya.; Kudryavtseva, L. A.; Shagidullina, R. A.; Валеева, Ф. Г.

doi:10.1016/s0167-7322(01)00244-6

Cited by 10 publications

(5 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sphere of our interest is the design of supramolecular catalytic systems for reactions of the transfer of the acyl and phosphoryl groups. ,− These reactions are of significance in organic chemistry and play a key role in biology . Catalytic effects of the single surfactant and the PEI systems on the nucleophilic substitution at carbon and phosphorus atoms are widely documented in the literature, our publications included. − Meanwhile the design of polymer + surfactant catalytic systems is a relatively novel field covered by only a few works, including our recent studies. ,,, The catalytic effects of the PEI + cationic surfactant systems on the hydrolytic reactions have been poorly studied, − and it remains unclear whether the catalysis observed is due to the mixed PEI + surfactant aggregates or results from the effects of individual components, i.e., polymer-free micelles and single PEI molecules.…”

Section: Introductionmentioning

confidence: 99%

“…The sphere of our interest is the design of supramolecular catalytic systems for reactions of the transfer of the acyl and phosphoryl groups. 4,[30][31][32] These reactions are of significance in organic chemistry and play a key role in biology. 33 Catalytic effects of the single surfactant and the PEI systems on the nucleophilic substitution at carbon and phosphorus atoms are widely documented in the literature, our publications included.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Polyethyleneimine + Cationic Surfactant Systems: Self-Organization and Reactivity Study

et al. 2010

View full text Add to dashboard Cite

The aggregation behavior and catalytic activity toward nucleophilic substitution in p-nitrophenyl acetate of the polyethyleneimine (PEI) + cationic surfactant systems is studied. The values of the critical aggregation concentrations are shown to be much lower as compared to critical micelle concentrations of single solutions. A decrease in the self-diffusion coefficient of surface-active ions is observed within the concentration range limited by the tensiometry critical points. The data obtained provide evidence for mixed aggregation in the PEI + cationic surfactant systems. Due to the contribution of specific interactions, surfactants with hydroxyethylated head groups cetyldimethyl(2-hydroxyethyl)ammonium bromide and cetylmethylbis(2-hydroxyethyl)ammonium bromide demonstrate a higher affinity toward PEI as compared to cetyltrimethylammonium bromide. The systems studied show catalytic activity toward the cleavage of p-nitrophenyl acetate, which increasees with the number of hydroxyethyl fragments in their head groups and reaches more than 2 orders of magnitude.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Polyethyleneimine + Cationic Surfactant Systems: Self-Organization and Reactivity Study

et al. 2010

View full text Add to dashboard Cite

show abstract

“…It was suitable for the low concentrations of ionic species where the ion‐exchange equilibrium parameters were taken as adjustable parameters in a model equation. Several scientists reported that in the micelle phase, the second‐order reaction rate constant was lower than the second‐order rate constant in the aqueous phase 1,20–22 . In that case, catalysis acted due to the enhancement of mass transfer of the ionic reactants at the aqueous–organic interface.…”

Section: Introductionmentioning

confidence: 99%

“…Several scientists reported that in the micelle phase, the second-order reaction rate constant was lower than the second-order rate constant in the aqueous phase. 1,[20][21][22] In that case, catalysis acted due to the enhancement of mass transfer of the ionic reactants at the aqueous-organic interface. It was reported in the literature that the pseudo first-order micelle-phase rate constants for the hydrolysis reactions of benzenesulfonyl chloride and benzoyl chloride were smaller than the first-order rate constants in the aqueous phase.…”

Section: Introductionmentioning

confidence: 99%

Modeling of micellar‐catalyzed bimolecular ionic reactions by a nonlinear Poisson−Boltzmann equation and an electrostatic free energy model

Karmakar

Jana

2023

Int J of Chemical Kinetics

View full text Add to dashboard Cite

The hydrolysis reactions of crystal violet (CV) and p‐nitrophenyl acetate (PNPA) by sodium hydroxide in cetyltrimethylammonium bromide (CTAB) micellar solution were studied in this work. Combined with the Boltzmann probability of ionic species in an electrostatic potential field, a model with a numerical scheme was developed based on the nonlinear Poisson−Boltzmann equation in the micelle‐cell consisting of the reactants and the surfactant. The numerical solution gives the ionic species distribution in the micelle phase and the radius of the micelle‐phase. The dielectric constant of the micelle‐phase varies in the range of 39.8−54.4. The second‐order reaction rate constants in the micelle‐phase were determined using the electrostatic and dipolar free energy models. For the basic hydrolysis of CV and PNPA, the overall second‐order rate constants are three to five times and 1.4 times greater than the corresponding values in water, respectively. The rate enhancement occurs due to the distribution of the reactive ionic species in the cell region and the enhancement of the Coulombic and dipolar interactions among the ionic and polar reactants.

show abstract

“…Badawi et al [9] studied the acceleration of Malathion hydrolysis in the presence of a micellar solution. Zakharova et al [10] have studied the basic hydrolysis of phosphate esters and showed the direct micelle concentration factors are mainly responsible for the acceleration of the nucleophilic reaction.…”

Section: Introductionmentioning

confidence: 99%

Degradation of Pesticides Wastewater by Silyl Based Cationic Surfactants

Badawi

Ahmed

2007

J Surfact & Detergents

View full text Add to dashboard Cite

New stable silayl cationic surfactants have been studied for the destruction of toxic organophosphorus pesticides. Hexadecyl, dodecyl trimethyl silane ammonium chloride or iodide surfactants were synthesized and evaluated in the degradation of pesticides such as Diazinon, Malathion or Chlorpyrifos. The hydrolytic efficiency of each surfactant was tested by measuring the kinetics of model substrates cleavage under a pseudo-first order reaction. The iodo silayl based surfactants showed more destructive power than the chloro derivatives. Meanwhile, the hexadecyl moiety showed more effective pesticide degradation than the corresponding dodecyl moiety.

show abstract

The factors determining the micellar effects on nucleophilic substitution reactions

Cited by 10 publications

References 4 publications

Polyethyleneimine + Cationic Surfactant Systems: Self-Organization and Reactivity Study

Polyethyleneimine + Cationic Surfactant Systems: Self-Organization and Reactivity Study

Modeling of micellar‐catalyzed bimolecular ionic reactions by a nonlinear Poisson−Boltzmann equation and an electrostatic free energy model

Degradation of Pesticides Wastewater by Silyl Based Cationic Surfactants

Contact Info

Product

Resources

About