123-93-3Relevant articles and documents
Spectroscopic investigation on kinetics, thermodynamics and mechanism for electron transfer reaction of iron(III) complex with sulphur centered radical in stimulated biological system
Deepalakshmi,Sivalingam,Kannadasan,Subramaniam,Sivakumar,Brahadeesh
, p. 315 - 321 (2014)
Electron transfer reactions of biological organic sulphides with several metal ions to generate sulphide radical cations are a great concern in biochemical process. To understand the mechanism, a stimulated biological system having model compounds, iron(III)-bipyridyl complex with thio-diglycolic acid (TDGA) was investigated. Spectroscopic study reveals the kinetics and thermodynamics of the reaction in aqueous perchloric acid medium. The reaction follows first and fractional order of 0.412 with respect to [Fe(bpy) 3]3+ and TDGA, respectively. The oxidation is insensitive to variation in [H+] but slightly decreases with increase in ionic strength ([I]). Addition of acrylamide, a radical scavenger has no effect on the rate of the reaction. The high negative value of ΔS# (-74.3 ± 1.09 J K-1 mol-1) indicates the complex formed has a definite orientation higher than the reactants. Based on the above results, a suitable reaction mechanism for this reactionis proposed.
Oxidation of thiol compounds by molecular oxygen in aqueous solutions
Bagiyan,Koroleva,Soroka,Ufimtsev
, p. 1135 - 1141 (2003)
Side self-oxidation of thiols was studied. It was found that these reactions in neutral and alkaline solutions are induced by impurities of variable-valence metals. The ability of transition metals to catalyze oxidation of thiols changes in the order Cu > Mn > Fe > Ni ? Co. The plot of the self-oxidation rate vs. pH passes through a maximum whose position on the pH scale depends on both the nature of metal and the structure of the thiol oxidized. For thiols having different structures, the kinetic orders in reactions catalyzed by copper ions differently vary with pH, which is apparently associated with the formation of complexes possessing different catalytic activity.
Zirconium oxide complex-functionalized MCM-41 nanostructure: An efficient and reusable mesoporous catalyst for oxidation of sulfides and oxidative coupling of thiols using hydrogen peroxide
Hajjami, Maryam,Shiri, Lotfi,Jahanbakhshi, Azar
, p. 668 - 673 (2015/09/28)
Zirconium oxide complex-functionalized mesoporous MCM-41 (Zr-oxide@MCM-41) as an efficient and reusable catalyst is reported for the oxidation of sulfides into sulfoxides using hydrogen peroxide (H2O2) as the oxidant, with short reaction times in good to excellent yields at room temperature under solvent-free conditions. Also, a simple and efficient method is reported for the oxidative coupling of thiols into corresponding disulfides in good to high yields using H2O2 as oxidant in the presence of Zr-oxide@MCM-41 as recoverable catalyst in ethanol at room temperature. A series of sulfides and thiols possessing functional groups was successfully converted into corresponding products. After completion of reactions the catalyst was easily separated with simple filtration from the reaction mixture and reused for several consecutive runs without significant loss of catalytic efficiency. The mesoporous catalyst was characterized using Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller surface area measurements, X-ray diffraction, transmission and scanning electron microscopies, energy-dispersive X-ray spectroscopy and thermogravimetric analysis.