67-71-0Relevant articles and documents
Kinetics and mechanism of oxidation of dimethyl sulphoxide by mono- and di-substituted N,N-dichlorobenzenesulphonamides in aqueous acetic acid
Gowda, B. Thimme,Jayalakshmi,Jyothi
, p. 787 - 794 (2003)
In an effort to introduce N,N-dichloroarylsulphonamides of different oxidising strengths, four mono- and five di-substituted N,N-dichlorobenzenesulphonamides are prepared, characterised and employed as oxidants for studying the kinetics of oxidation of dimethyl sulphoxide (DMSO) in 50% aqueous acetic acid. The reactions show first order kinetics in [oxidant], fractional to first order in [DMSO] and nearly zero order in [H +]. Increase in ionic strength of the medium slightly increases the rates, while decrease in dielectric constant of the medium decreases the rates. The results along with those of the oxidation of DMSO by N,N-dichlorobenzenesulphonamide and N,N-dichloro-4-methylbenzenesulphonamide have been analysed. Effective oxidising species of the oxidants employed in the present oxidations is Cl+ in different forms, released from the oxidants. Therefore the introduction of different substituent groups into the benzene ring of the oxidant is expected to affect the ability of the reagent to release Cl+ and hence its capacity to oxidise the substrate. Significant changes in the kinetic and thermodynamic data are observed in the present investigations with change of substituent in the benzene ring. The electron releasing groups such as CH3 inhibit the ease with which Cl+ is released from the oxidant, while electron-withdrawing groups such as Cl enhance this ability. The Hammett equation, log kobs = -3.19 + 1.05 σ, is found to be valid for oxidations by all the p-substituted N,N-dichlorobenzenesulphonamides. The substituent effect on the energy of activation, Ea and log A for the oxidations is also analysed. The enthalpies and free energies of activation correlate with an isokinetic temperature of 320 K.
Kinetics and mechanism of oxidation of dimethyl sulfoxide with benzoyl peroxide in superbasic media
Lyavinets,Marushchak
, p. 885 - 889 (2004)
Oxidation of dimethyl sulfoxide with benzoyl peroxide in some dipolar aprotic solvents and superbasic media was studied. The kinetic parameters were correlated with the main physicochemical characteristics of solvents. The oxidation rate grows with increasing donor number and polarizability of the solvent. A two-step scheme of dimethyl sulfoxide oxidation with benzoyl peroxide in superbasic media was suggested, involving preliminary cleavage of the peroxide to perbenzoate with the base. In the reaction, sodium tert-butylate is preferable over sodium hydroxide.
Micellar effect on the reaction of picolinic acid catalyzed chromium(VI) oxidation of dimethyl sulfoxide in aqueous acidic media: A kinetic study
Das,Mondal,Kar,Das
, p. 173 - 181 (2001)
The kinetics and mechanism of picolinic acid (PA) catalyzed oxidation of dimethyl sulfoxide (DMSO) to dimethyl sulfone by chromium(VI) in both aqueous H2SO4 and HClO4 media have been studied in the absence and presence of surfactants at different temperatures. Cr(VI)-PA complex formed in preequilibrium steps is the active oxidant that experiences the nucleophilic attack by DMSO to form a positively charged intermediate ternary complex. Within the proposed ternary complex, an oxygen transfer or a ligand coupling or both occurs to generate the product, dimethyl sulfone. Cr(VI) is ultimately converted to Cr(III)-PA complex. Under the experimental conditions, the process shows a first-order dependence on each of the reactants (i.e., [Cr(VI)]T, [PA]T, [DMSO]T, and [H+]). HCrO4- has been found kinetically active. The reaction is catalyzed by sodium dodecyl sulfate (SDS, a representative anionic surfactant) monotonically, while cetylpyridinium chloride (CPC, a representative cationic surfactant) retards the reaction continuously. The observed micellar effects have been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. A pseudo-phase ion exchange (PIE) model has been applied to explain the micellar effect. The Piszkiewicz cooperative model has been applied to determine the kinetic parameters, and it indicates the existence of catalytically productive submicellar aggregates. Because of this reactant-promoted micellization of the surfactant before or below the cmc value, the present systems do not show any discontinuity at the respective reported cmc values of the surfactants.
Synthesis of new polyfluorinated oxaziridines
Petrov, Viacheslav,Marshall, Will
, p. 1 - 6 (2018)
The article describes a synthesis of new per- and polyfluorinated oxaziridines along with some reactions of these materials.
OXIDATION OF DIMETHYLSUPHOXIDE BY SODIUM N-BROMOBENZENESULPHONAMIDE: A KINETIC AND MECHANISTIC STUDY
Mahadevappa, D.S.,Ananda, S.,Murthy, A.S.A.,Rangappa, K.S.
, p. 1673 - 1682 (1984)
The kinetics of oxidation of dimethylsulphoxide (DMSO) by sodium N-bromobenzenesulphonamide or bromamine-B (BAB) has been studied in HClO4, HCl and NaOH media, at 35 deg C, with OsO4 as a catalyst in the latter medium.In acid medium, the rateshows a first order dependence on and second order in +>, but is independent of substrate concentration.Alkali retards the reaction (inverse first order) and rate is independent of oxidant concentration, but shows fractional order in and depends on 4>2.The solvent isotope effect was studied by using D2O.Activation parameters have also been determined.Mechanisms pro posed and the derived rate laws are consistent with the observed kinetics.
Oxidation of dimethyl sulfoxide with hydrogen peroxide in the presence of potassium hydroxide
Choban,Yurchuk,Lyavinets
, p. 2071 - 2074 (2008)
Kinetic relationships in oxidation of DMSO to dimethyl sulfone with hydrogen peroxide in the presence of potassium hydroxide were studied. Kinetic parameters of the process were calculated. It was established that the reaction proceeded through the intermediate formation of potassium hydroperoxide.
Polyoxometalate nanocone nanoreactors: Magnetic manipulation and enhanced catalytic performance
Nisar, Amjad,Lu, Yao,Zhuang, Jing,Wang, Xun
, p. 3187 - 3192 (2011)
Magnetic personality: Nanocone nanoreactors consisting of polyoxometalates functionalized with surfactant alkyl chains and magnetite nanocrystals (NCs) provide enhanced catalytic performance for the oxidation of sulfides to sulfones by a trap-release mechanism and advanced catalyst recovery under an external magnetic field. Copyright
Effect of base nature on the oxidation of dimethyl sulfoxide with hydrogen peroxide in superbasic media
Choban,Yurchuk,Lyavinets
, p. 247 - 250 (2012)
Kinetic relationships of the dimethyl sulfoxide oxidation to dimethyl sulfone with hydrogen peroxide in the presence of an alkali (MOH) or sodium tert-butoxide were investigated. Kinetic parameters of the process were calculated. The process was found to proceed through the intermediate formation of the alkaline salts MeOOH. The effect of the base nature on the stage of salt formation and oxidation was revealed. Pleiades Publishing, Ltd., 2012.
Oxygen-atom-transfer reactions of a palladium(II) peroxocarbonate complex
Sase, Shohei,Hashimoto, Maki,Goto, Kei
, p. 157 - 159 (2015)
Reactivity of a palladium(II) peroxocarbonate complex was investigated. It was found that a bis(N-heterocyclic carbene) palladium(II) peroxocarbonate acts as an oxygen-atom-transfer (OAT) reagent toward a phosphine and a sulfoxide. In these OAT reactions, the peroxocarbonate was converted to the corresponding palladium(II) carbonate. While the OAT reaction toward triphenylphosphine proceeded only sluggishly, addition of lithium chloride remarkably facilitated the reaction. It was proposed that the chloride ion induces the liberation of the peroxocarbonate moiety from the coordination sphere of palladium.
Kinetics and Mechanism of Picolinic Acid Promoted Chromium(vl) Oxidation of Dimethyl Sulfoxide in the Presence and Absence of Surfactants
Das, Asim K.,Mondal, Sudhin K.,Kar, Dalia,Das, Mahua
, p. 574 - 575 (1998)
In the picolinic acid (PA) promoted Crv! oxidation of dimethyl sulfoxide (DMSO), the Crv'-PA complex formed at the pre-equilibrium step undergoes nucleophilic attack by the S of DMSO to form a positively charged reactive intermediate which experiences an oxygen transfer or a ligand coupling to give the products; the anionic surfactant (SDS) accelerates the process while the cationic surfactant (CPC) retards the reaction.
