505-73-7Relevant articles and documents
Martin,Spence
, p. 3589 (1970)
Cu(II)-catalyzed oxidation of thiols by superoxide ligated to Co III2
Mishra, Ritu,Banerjee, Rupendranath,Mukhopadhyay, Subrata
, p. 1193 - 1197 (2012)
Copper(II) dramatically catalyzes the oxidation of thiols by a superoxide bridging two CoIII ions. The catalyzed path overwhelmingly dominates over the uncatalysed path and is first order in the superoxo complex concentration. The first-order rate constants show a first-order dependence in [Cu2+], a second-order dependence in [thiol] and linearly varies with [H+]-3. On the basis of observed kinetics reported here, it is proposed that Cu(II) reacts with two thiol molecules to form a Cu II(thiol)2 complex, an electron is transferred from one ligated thiol to the CuII center to form CuI(thiol) and a thiyl radical. The copper(I)-thiol complex is oxidized by the conjugate base of the title complex to regenerate CuII(thiol). A CuII/I catalytic cycle is thus believed to be responsible for the observed catalysis. Copyright
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Henderson,Winkler
, p. 1082 (1959)
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Determination of Thioglycolic Acid and Dithiodiglycolic Acid in Mineral Flotation Systems
McLean, McLean,Wagenen, Stan Van,Wiedemann, Donna,Fernando, Quintus,Raghavan, Srini
, p. 965 - 969 (1986)
When aqueous solution of thioglycolic acid are equilibrated with sphalerite, a zinc sulfide mineral, a large fraction of the thioglycolic acid is either adsorbed on the sphalerite surface or oxidized ot dithiodiglycolic acid.The total concentration of thioglycolic and dithioglycolic acid in solution has been determined by molecular emission cavity analysis (MECA).The fraction of the thioglycolic acid that is not adsorbed on the mineral surface and remains in solution has been determined by a coulometric titration in which iodine is electrogenerated in situ and the endpoint located by an amperometric method.Attempts to determine the thioglycolic acid that was adsorbed on the mineral surface directly by MECA gave unreliable results.This has been attributed to the wide variation in the surface area as well as the surface chemical composition of small samples (1-2 mg) of the mineral that must be useed in the sample cup in MECA.Thioglycolic acid also leaches traces of metal ions from the mineral surface.The concentration of zinc(II) in solution reflects the extent of leaching that has occurred.
l-Arginine complex of copper on modified core–shell magnetic nanoparticles as reusable and organic–inorganic hybrid nanocatalyst for the chemoselective oxidation of organosulfur compounds
Nikoorazm, Mohsen,Moradi, Parisa,Noori, Nourolah,Azadi, Gouhar
, p. 467 - 478 (2020/09/01)
In this paper, we report the fabrication and characterization of a stable heterogeneous nanostructure catalyst of copper immobilized on Fe3O4@SiO2@l-Arginine, for the oxidation of sulfides and oxidative coupling of thiols. The prepared nanocatalyst has been characterized by different techniques such as FTIR, XRD, SEM, TEM and TGA. These nanoparticles were the effective catalyst for selective oxidation of sulfides and oxidative coupling of thiols using 30% H2O2. The suggested method offers several prominent advantages such as mild condition, use of magnetically reusable catalyst, simple workup procedure, good to high yields of products and great selectivity.
Fe3O4@MCM-41@Zn-Arg: as a novel, magnetically recoverable and ecofriendly nanocatalyst for the synthesis of disulfides, sulfoxides and 2,3-dihydroquinazolin?4(1H)?ones
Nikoorazm, Mohsen,Erfani, Zahra
, p. 642 - 655 (2020/08/19)
The direct supporting of Zn-arginine complex on magnetic core-shell nanostructures (Fe3O4@MCM-41@Zn-Arg) was reported as a novel, heterogeneous and excellent nanocatalyst, which applied for the oxidation reaction of sulfides to sulfoxides, oxidative coupling of thiols to their corresponding disulfides and the synthesis of 2,3-dihydroquinazolin-4(1H)-one derivatives under mild conditions. The structure of the catalyst was studied by X-Ray diffraction, Fourier transform-infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, atomic absorption spectroscopy, and vibrating sample magnetometry techniques. The simple experimental procedure, very good catalytic activity, low cost, and excellent recycling are the noteworthy features of the currently employed heterogeneous catalytic system.
SUPER-HYDROPHOBIC ELECTROTHERMAL EPOXY RESIN COMPOSITE MATERIAL AND PREPARATION AND SELF-REPAIRING METHOD THEREFOR
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, (2020/12/25)
Superhydrophobic electrothermal epoxy composites, their preparation and a self-healing method are disclosed. 1,4,5-oxadithiepane-2,7-dione and methylhexahydrophthalic anhydride were mixed and cured with epoxides to get self-healable epoxy resins; carbon nanotube/self-healable epoxy resin prepolymers were coated on self-healable epoxy resins and cured to get electrothermal epoxy composites; modified superhydrophobic copper powders were adhered on electrothermal epoxy composites and cured to get a kind of superhydrophobic electrothermal epoxy composites. The thermal resistance of superhydrophobic electrothermal epoxy composites is superior to existed technical solutions and they can simultaneously repair cracking and delamination and the healed samples still exhibit excellent superhydrophobicity. These merits of superhydrophobic electrothermal epoxy composites provided in this invention can meet the harsh requirements of self-healing and removing ice on surfaces of wind turbine blades, suggesting good abilities of guaranteeing service safety and lifespan of wind turbine blades.