1892-29-1Relevant articles and documents
Kinetics and Mechanisms of the Reduction of Cobalt(II) 4,4',4'',4'''-Tetrasulfophthalocyanine by 2-Mercaptoethanol under Anoxic Conditions
Leung, Ping-Sang K.,Betterton, Eric A.,Hoffmann, Michael R.
, p. 430 - 433 (1989)
The kinetics and mechanism of reduction of cobalt(II) 4,4',4'',4'''-tetrasulfophthalocyanine by 2-mercaptoethanol to yield cobalt(I) tetrasulfophthalocyanine and 2-hydroxyethyl disulfide under anoxic conditions were investigated and the following rate law was found: ν = -dIITSP>T/dt = 2K1TIITSP>T>/H+/Ka1 + Ka2/aH+)(1 + αT)>, where k2 is a rate constant for the rate-limiting electron-transfer step, and K1 is the equilibrium constant for the complexation of a CoTSP dimer with thioethanol; Ka1 and Ka2 are the apparent acid dissociation constants of HOC2H4SH and HOC2H4S-, respectively; α is K1/(1 + aH+/Ka1 + Ka2/aH+); aH+ is the hydrogen ion activity.A nonlinear least-squares fit of the experimental data to the above rate law gave k2 = 228 +/- 3.8 s-1 and K1 = 117 +/- 2.5 M-1 at 27 deg C at μ = 0.4 M.
Chalcogen-containing analogs of ethylene glycol and its derivatives
Vshivtsev,Levanova,Grabel'nykh,Sukhomazova,Albanov,Klyba,Zhanchipova,Russavskaya,Kochervin
, p. 608 - 613 (2008)
Ethylene chlorohydrin when reacted with elemental chalcogens or dimethyl dichalcogenides in the hydrazine hydrate-alkali system forms chalcogen-containing analogs of ethylene glycol and its derivatives (dichalcogenated β-diglycols, chalcogenated ethanols, and chalcogenated methyl cellosolves).
Coleman,Blout
, p. 2405,2407, 2408 (1968)
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Vints,V.V. et al.
, (1973)
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Thiol-dependent DNA cleavage by 3H-1,2-benzodithiol-3-one 1,1-dioxide
Breydo, Leonid,Gates, Kent S.
, p. 885 - 889 (2000)
Hydrodisulfides (RSSH) have previously been implicated as key intermediates in thiol-triggered oxidative DNA damage by the antitumor agent leinamycin. In an effort to better understand DNA damage by RSSH and to expand on the number and type of chemical systems that produce this reactive intermediate, the ability of 3H-1,2-benzodithiol-3-one 1,1-dioxide (11) to serve as a thio-dependent DNA cleaving agent has been investigated. The findings reported here indicate that reaction of 11 with thiols results in release of RSSH and subsequent oxidative DNA strand cleavage. (C) 2000 Elsevier Science Ltd. All rights reserved.
Kinetics and mechanism of oxygen atom abstraction from a dioxo-rhenium(VII) complex
Dixon, JaNeille,Espenson, James H.
, p. 4727 - 4731 (2002)
The kinetics of reaction between triarylphosphanes and two newly prepared dioxorhenium(VII) compounds has been evaluated. The compounds are MeReVII(O)2( O,S ) in which O,S represents an alkoxo, thiolato chelating ligand. With MeReO3, ligands derived from 1-mercaptoethanol and 1-mercapto-2-propanol form MeRe(O)2(met), 2, and MeRe(O)2(m2p), 3. These compounds persist in chloroform solution for several hours at room temperature and for 2-3 weeks at -22°C, particularly when water is carefully excluded. They were obtained as red oils with clean 1H NMR spectra, but attempts to obtain pure, crystalline products were not successful because one decomposition pathway shows a kinetic order >1. The fastest reaction occurs between P(p-MeOC6H4)3 and 2; k298 = 215(7) L mol-1 s-1 in chloroform at 25(1)°C. The other rate constants follow a Hammett correlation against 3σ, with ρ = -0.69(7). This study relates to oxygen atom transfer reactions catalyzed by MeReO(mtp)PPh3, 1, in which MeRe(O)2(mtp), 4, is a postulated intermediate that does not build up to a measurable concentration during the catalytic cycle. Compound 2 does not react with MeSTol, but MeS(O)Tol was formed when tert-butyl hydroperoxide was added. This suggests that equilibrium lies to the left in this reaction, 2 + MeSTol + L = MeReO(met)L + MeS(O)Tol, and is drawn to the right by a reaction between MeReO(met)L and the hydroperoxide. Triphenyl arsane does not react with 2, but thermodynamic versus kinetic barriers were not resolved.
Silica sulfuric acid/NaNO2 as a novel heterogeneous system for production of thionitrites and disulfides under mild conditions
Zolfigol, Mohammad Ali
, p. 9509 - 9511 (2001)
Neat chlorosulfonic acid reacts with silica gel to give silica sulfuric acid in which sulfuric acid is immobilized on the surface of silica gel via covalent bond. Thiols can be readily converted to their corresponding thionitrites with a combination of silica sulfuric acid, wet SiO2 and sodium nitrite in dichloromethane at room temperature. Disulfides result from the homolytic cleavage of the sulfur-nitrogen bond of the unstable thionitrites and subsequent coupling of the resultant thiyl radicals.
One-Pot Construction of Sulfur-Rich Thermoplastic Elastomers Enabled by Metal-Free Self-Switchable Catalysis and Air-Assisted Coupling
Wu, Guang-Peng,Xie, Rui,Yang, Guan-Wen,Zhu, Xiao-Feng
supporting information, (2021/12/27)
Construction of well-defined sulfur-rich macromolecules in a facile manner is an interesting but challenging topic. Herein, we disclose how to readily construct well-defined triblock sulfur-rich thermoplastic elastomers via a self-switchable isothiocyanate/episulfide copolymerization and air-assisted oxidative coupling strategy. During self-switchable polymerization, alternating copolymerization of isothiocyanate and episulfide occurs initially due to the lower energy barrier for isothiocyanate insertion with respect to successive episulfide ring-opening. After exhaustion of isothiocyanate, ring-opening polymerization of episulfide begins, providing diblock polymers. Subsequent exposure of the reaction to air leads to a transformation of diblock copolymers into triblock thermoplastic elastomers. This protocol can be extended to diverse isothiocyanates and episulfides, allowing fine-tuning of the performance of the produced sulfur-rich thermoplastic elastomers.
Copper based on diaminonaphthalene-coated magnetic nanoparticles as robust catalysts for catalytic oxidation reactions and C-S cross-coupling reactions
Yarmohammadi, Nasrin,Ghadermazi, Mohammad,Mozafari, Roya
, p. 9366 - 9380 (2021/03/16)
In this work, the immobilization of copper(ii) on the surface of 1,8-diaminonaphthalene (DAN)-coated magnetic nanoparticles provides a highly active catalyst for the oxidation reaction of sulfides to sulfoxides and the oxidative coupling of thiols to disulfides using hydrogen peroxide (H2O2). This catalyst was also applied for the one-pot synthesis of symmetrical sulfidesviathe reaction of aryl halides with thiourea as the sulfur source in the presence of NaOH instead of former strongly basic and harsh reaction conditions. Under optimum conditions, the synthesis yields of sulfoxides, symmetrical sulfides, and disulfides were about 99%, 95%, and 96% respectively with highest selectivity. The heterogeneous copper-based catalyst has advantages such as the easy recyclability of the catalyst, the easy separation of the product and the less wastage of products during the separation of the catalyst. This heterogeneous nanocatalyst was characterized by FESEM, FT-IR, VSM, XRD, EDX, ICP and TGA. Furthermore, the recycled catalyst can be reused for several runs and is economically effective.
