Mechanistic aspects of oxidation of dextrose by N-bromophthalimide in acidic medium: a micellar kinetic study

Application of Piszkiewicz model on the electron transfer reaction of dithionite ion and bis-(2-pyridinealdoximato)dioxomolybdate(IV) complex

The need to better understand the binding mode of antioxidants (sulfur oxyanions) kinetically is a concern in medicine. Hence, a spectrophotometric method was used to study the application of the Piszkiewicz model on the electron transfer reaction of dithionite ion (S₂O₄^2-) and bis-(2-pyridinealdoximato)dioxomolybdate(IV) complex at 303 K and an absorption maxima of 560 nm. It follows an acid dependent reductive pathway that is medium sensitive. Charge distribution from the reaction species contributes to the redox efficiency of the system, resulting in a primary salt effect (NaCl) with an enhanced reaction rate. Alteration of the reaction medium with ethanol led to an elevation of reduction time as the charge catalysis was distorted by a drop in the system permittivity. Likewise, sodium dodecyl sulfate in the system decreased the reduction rate of the complex due to the low impact of hydrophobic and ion interaction between the micelle and substrates. First order reaction kinetics was observed in the concentration of the redox partners and a 2:1 (complex: S₂O₄^2-) stoichiometry was obtained with the involvement of hydrogenated sulfite radical which resulted in the formation of sulfur dioxide and a Mo²⁺ deactivated complex. The occurrence of counterion catalysis is pronounced in the reaction system owing to the participation of like-charged substrates in the rate-controlling phase. The standard enthalpy (69.12 [Formula: see text] 0.05 kJ mol^-1) and Gibbs energy (80.10 [Formula: see text] 0.07) kJ mol^-1 suggest that the process is endothermic dependent. The investigation of the anionic surfactant effect on the reaction medium was quantitatively ascertained from the Piszkiewicz model of the complex interaction sequence.

Potential application of Micellar nanoreactor for electron transfer reactions mediated by a variety of oxidants: A review

Surfactant, either natural or synthetic, forms a different type of aggregates among which 'Micelle' is truly an important dynamic surfactant aggregate, having a different region to interact with several organic, inorganic, and biomolecules; therefore the practical use of micelle is rapidly growing day-to-day. Surfactant-micelle, looks like a reactor of nano-dimension, govern a variety of reactions in aqueous media extensively. Oxidation is one of the vital reaction, take a part in the course of several organic transformations which are not very easy to execute in water media alone due to the solubility problem. Moreover, in order to achieve a quick transformation overcoming several difficulties the utility of micellar media became an excellent innovation, that's why nowadays, the surfactant and its aggregates are a focus of interest to the researcher of synthetic field and thus its practical applicability has been tremendously cultivated over the few decades. It is, therefore, useful to introduce some basic concepts regarding the aggregation of surfactants. Subsequently, we emphasize the importance of micellar media on the kinetics of oxidation reactions mediated by several metal ions with a special emphasis on their catalytic role.