110-81-6Relevant articles and documents
Gas-phase reactions of O(3P) atoms with methanethiol, ethanethiol, methyl sulfide, and dimethyl disulfide. 2. Reaction products and mechanisms
Cvetanovic,Singleton,Irwin
, p. 3530 - 3539 (1981)
In conjunction with the determinations of the rate constants of reactions of the ground-state oxygen atoms, O(3P), with methanethiol, ethanethiol, methyl sulfide, and dimethyl disulfide described in the preceding paper,3 a parallel study was carried out of the products and mechanisms of the same reactions at 300 K. Oxygen atoms were generated by the mercury-photosensitized decomposition of N2O, used in large excess, and the recovered products were analyzed by gas chromatography. The total pressure was varied from 300 to 1200 torr. Nitrogen formed in the photosensitized decomposition of N2O provided a direct measure of the number of O atoms generated and allowed determination of the yields of some of the products per oxygen atom reacting with the sulfur organic compounds. From a detailed analysis of the experimental results obtained with single sulfur organics and their mixtures, it is possible to derive substantial quantitative information on the reaction mechanisms. The postulated overall reaction mechanisms include some novel features common to the thiols, sulfide, and disulfide studied, which provide a simple explanation for some unexpected experimental trends observed.
Kinetics and Mechanism of the Autoxidation of 2-Aminoethanethiol and Ethanethiol Catalyzed by Cobalt(II) 4,4',4'',4'''-Tetrasulfophthalocyanine in Aqueous Solution
Leung, Ping-Sang K.,Hoffmann, Michael R.
, p. 434 - 441 (1989)
The kinetics of autoxidation of 2-aminoethanethiol to 2-aminoethyl disulfide and ethanethiol to ethyl disulfide as catalyzed by cobalt(II) 4,4',4'',4'''-tetrasulfophthalocyanine (CoIITSP) were investigated.The following general rate law found to hold for both substrates over the pH range 8.8-13.5: ν = -d->/dt = kobsdT->.Evidence for a mechanism that proceeds via a dimeric catalytic center that is bridged by the RS- anion has been obtained.In the proposed mechanism, electron transfer from the Co(II) metal center to bound dioxygen was considered to the rate-determining step.Hydrogen peroxide and mercaptan radical were identified as reaction intermediates in the autoxidation of both substrates.These intermediates react further to produce the correponding disulfide, RSSR. as the final product of the autoxidation. kobsd was found to be of the following general form: kobsd = (k31K21 + (k32K22K'1/aH+) + (k33K23K'1K'2/aH+2))/1/aH+) + (K'1K'2/aH+2))(1 + (aH+/K'a12))>, where k3i and K2i are the rate constants for the electron transfer and the equilibrium constants for substrate complexation of the ith catalytic center, respectively, K'1 and K'2 are the apparent acid dissociation constants of the pyrrole groups of CoIITSP-RS--CoIITSP and CoIITSP-RS--CoIITSP-, respectively, and K'a1 is the apparent acid dissociation constant of RCH2CH2SH.
Universal Anticancer Cu(DTC)2 Discriminates between Thiols and Zinc(II) Thiolates Oxidatively
Xu, Luyan,Xu, Jialin,Zhu, Jingwei,Yao, Zijian,Yu, Na,Deng, Wei,Wang, Yu,Lin, Bo-Lin
, p. 6070 - 6073 (2019)
Aerobic organisms must rely on abundant intracellular thiols to reductively protect various vital functional units, especially ubiquitous zinc(II) thiolate sites of proteins, from deleterious oxidations resulting from oxidizing environments. Disclosed here is the first well-defined model study for reactions between zinc(II) thiolate complexes and copper(II) complexes. Among all the studied ligands of copper(II), diethyldithiocarbamate (DTC) displays a unique redox-tuning ability that enables copper(II) to resist the reduction by thiols while retaining its ability to oxidize zinc(II) thiolates to form disulfides. This work proves for the first time that it is possible to develop oxidants to discriminate between thiols and zinc(II) thiolates, alluding to a new chemical principle for how oxidants, especially universal anticancer Cu(DTC)2, might circumvent the intracellular reductive defense around certain zinc(II) thiolate sites of proteins to kill malignant cells.
Graphite oxide: A selective and highly efficient oxidant of thiols and sulfides
Dreyer, Daniel R.,Jia, Hong-Peng,Todd, Alexander D.,Geng, Jianxin,Bielawski, Christopher W.
, p. 7292 - 7295 (2011)
The selective oxidation of thiols to disulfides and sulfides to sulfoxides using graphite oxide (GO), a heterogeneous carbocatalyst obtained from low cost, commercial starting materials is described. The aforementioned oxidation reactions were found to proceed rapidly (as short as 10 min in some cases) and in good yield (51-100%) (19 examples). No over-oxidation of the substrates was observed, and GO's heterogeneous nature facilitated isolation and purification of the target products.
Catalytic oxidation of thiols to disulfides with vanadyl acetylacetonate (VO(ACAC)2)
Raghavan,Rajender,Joseph,Rasheed
, p. 1477 - 1480 (2001)
Catalytic amounts of VO(acac)2 coupled with t-butylhydroperoxide chemoselectively oxidizes thiols to disulfides under mild reaction conditions and is generally useful for a wide variety of thiols.
An efficient and mild cleavage of thiol acetate with clayfen in the absence of solvent
Meshram, Harshadas M.
, p. 2521 - 2522 (1993)
The disulphides are synthesised through the mild cleavage of thiol acetate with clayfen in the absence of solvent.
C-S Bond Cleavage, Redox Reactions, and Dioxygen Activation by Nonheme Dicobalt(II) Complexes
Jana, Manish,Majumdar, Amit
, p. 617 - 632 (2018)
Synthesis and reactivity of a series of thiolate/thiocarboxylate bridged dicobalt(II) complexes were investigated in comparison with their carboxylate bridged analogues bearing free thiol/hydroxyl groups. Upon one-electron oxidation, complexes [Co2(N-Et-HPTB)(μ-SR1)](BF4)2 (R1 = Ph, 1a; Et, 1b; Py, 1c) and [Co2(N-Et-HPTB)(μ-SCOR2)](BF4)2 (R2 = Ph, 2a; Me, 2b) yielded [Co2(N-Et-HPTB)(DMF)2](BF4)3 (6) (DMF = dimethylformamide) along with the corresponding disulfides (where N-Et-HPTB is the anion of N,N,N′,N′-tetrakis[2-(1-ethylbenzimidazolyl)]-2-hydroxy-1,3-diaminopropane). Unlike the inertness of carboxylate bridged complexes [Co2(N-Et-HPTB)(μ-O2C-R3-SH)](BF4)2 (R3 = Ph, 3a; CH2CH2, 3b) and [Co2(N-Et-HPTB)(μ-O2CR4)](BF4)2 (R4 = Ph, 4a; Me, 4b; CH2CH2CH2OH, 5) toward O2, the bridging ethanethiolate in 1b was oxidized to yield a sulfinate bridged complex, [Co2(N-Et-HPTB)(μ-O2SEt)](BF4)2 (10). Detailed investigation of the synthetic aspects of 1a-1c led to the discovery of a C-S bond cleavage reaction and yielded the dicobalt(II) complexes [Co2(N-Et-HPTB)(SH)(H2O)](BF4)2 (8a), [Co2(N-CH2Py-HPTB)(SH)(H2O)](BF4)2 (8b) (where N-CH2Py-HPTB is the anion of N,N,N′,N′-tetrakis[2-(1-picolylbenzimidazolyl)]-2-hydroxy-1,3-diaminopropane)), and [Co2(N-Et-HPTB)(μ-S)](BF4) (9). Both 8a and 8b feature nonheme dinuclear Co(II) units containing a terminal hydrosulfide. The present study thus reports comparative redox reactions for a rare class of 16 dicobalt(II) complexes and introduces a selective synthetic strategy for the synthesis of unprecedented dicobalt(II) complexes featuring only one terminal hydrosulfide.
Aerobic oxidation of thioglycol catalysed by metallophthalocyanine in an organic-inorganic hybrid vesicle “cerasome”
Hisaeda, Yoshio,Kikuchi, Jun-ichi,Sasaki, Yoshihiro,Song, Xi-Ming,Wu, Qiuhua,Yasuhara, Kazuma,Zhang, Dan,Zhang, Guolin,Zhang, Li
, (2020)
A molecular assembly of a hydrophobized metallophthalocyanine derivative embedded in a cerasome, an organic–inorganic hybrid vesicle with a lipid bilayer and silica surface, was a potent catalyst for aerobic oxidation of thioglycol. The catalytic activity was higher than those in hexadecyl 2-hydroxy-3-chloropropyl phosphate vesicles, sodium dodecylsulfate micelles, ethanol, and benzene.
Oxidative dimerization of thiols to disulfide using recyclable magnetic nanoparticles
Masnabadi, Nasrin,Ghasemi, Mohammad Hadi,Beyki, Mostafa Hossein,Sadeghinia, Mohammad
, p. 1609 - 1618 (2017)
Abstract: Dimerization of thiol groups to disulfide is an important transformation in chemical processes. In this study, magnetic ion exchanged Montmorillonite-k10 was synthesized and characterized using FTIR, X-ray diffraction and scanning electron microscope techniques. Then, the application of the synthesized catalyst as an efficient oxidizing agent was evaluated in oxidative dimerization of different thiols to corresponding disulfides under optimal reaction conditions. The reaction was easily performed with aromatic, aliphatic and heterocyclic thiols. The magnetic catalyst was easily recovered by applying an external magnet and, further, was reused in successive reactions. Graphical Abstract: [Figure not available: see fulltext.]
Synthesis, structure and DFT study of asymmetrical NHC complexes of cymantrene derivatives and their application in the dehydrogenative dimerization reaction of thiols
Fraser, Roan,van Rooyen, Petrus H.,de Lange, Jurgens,Cukrowski, Ignacy,Landman, Marilé
, p. 11 - 22 (2017)
Asymmetrical NHC complexes of cymantrene and methylcymantrene have been synthesised through the photochemical substitution of carbonyl ligands in the presence of the imidazol-2-ylidene salts. The carbene substituents have been varied between compact (L1) and bulky (L2 and L3) substituents to produce an array of differently sized carbene ligands. The solid state crystal structures of three of the complexes confirmed the bonding pattern of the ligand towards available metal centres and an in-depth DFT study provided insight into electronic and steric aspects. Application of the Extended Transition State coupled with Natural Orbitals for Chemical Valence (ETS-NOCV) energy decomposition technique indicated various NOCV channels for each Mn–L bond (L?=?3-ethyl-1-methylimidazolylidene carbene, triphenylphosphine or acetonitrile), describing the density and energy changes of specific (σ and π) attributes of each bond. N-heterocyclic carbenes of cymantrene derivatives and their triphenylphosphine-substituted analogue are equivalent σ-donors, with 53% and 56%, respectively, of the total binding energy originating from σ-donation. However, NHC complexes show considerably less π character in the metal-carbene bond. Hydrogen interactions in the NHC complexes were also identified in the ETS-NOCV calculations and provided quantification of the hydrogen interactions witnessed in the solid state structures. Calculated Wiberg bond indices, bond dissociation enthalpies, percentage buried volumes and percentage sigma and pi-bonding characteristics quantified the bonding and electronic aspects of the ligand-metal interactions within the complex.
