Reaction Of Disulfide Research Articles

A green and efficient synthesis of alkyl 2-((5-hydroxy-1H-pyrazole-4-carbonothioyl)thio)acetates via a one-pot, solvent-free reaction

A green and efficient synthesis of alkyl 2-((5-hydroxy-1H-pyrazole-4-carbonothioyl)thio)acetates is described. The method involves a one-pot, solvent-free reaction of pyrazolone derivatives, carbon disulfide, and alkyl bromoacetates in the presence of triethylamine. The crude products were readily purified by simple water washing followed by recrystallization from diethyl ether. The structures of the synthesized pyrazole-4-carbonothioyl-thio-acetate derivatives were confirmed by IR, 1H NMR, 13C NMR, and mass spectrometry.

Role of Solvent and Noncovalent Interactions in Alkaline Reactivity of Strained and Strain-Free Macrocyclic Disulfides.

This study employs ab initiomolecular dynamics simulations to investigate the impact of solvent and non-bonded interactions on the structure-reactivity relationship of both strain-free and strained macrocyclic disulfides. Our findings reveal that interactions with water as a solvent significantly influence the minimum energy geometry structures of both conformers of the studied macrocycle. In particular, our simulations identify short contacts, specifically S···π-aromatic interactions, which suppress reactivity for the strained isomer by obstructing the reaction cone at the minimum free energy. Surprisingly, the free energy barriers for the disulfide reaction with a simple nucleophile (OH-anion) remain very similar, despite one conformer having a markedly more strained disulfide bond than the other. Enhanced molecular dynamics simulations in explicit solution elucidate this apparent contradiction by revealing different solvent exposures of the two sulfur atoms in the macrocycles.

Nickel-Catalyzed Enantioselective Reductive N-Cyclization-Thiolation Reaction of Alkene-Tethered Oxime Esters and Disulfides.

Asymmetric aza-Heck cyclization and coupling reactions offer efficient access to enantioenriched N-heterocycles, yet the current studies focus primarily on sequential C-N and C-C bond formation. Herein, we report an enantioselective reductive aza-Heck cyclization followed by a C-S coupling sequence, ultimately yielding sulfide-containing enantioenriched pyrrolines. The reaction is conducted under mild conditions and tolerates broad functionalities including alkynes, phenols, anilines, amides, nitriles, and bromides.

Chain Extension of Piperazine in Ethanol: Synthesis of 2-(4-(2-(Phenylthio)ethyl)piperazinyl)acetonitriles and ACAT-1 Inhibitors.

A base-induced synthesis of 2-(4-(2-(phenylthio)ethyl)piperazinyl) acetonitriles by reaction of disulfides, 1-(chloromethyl)-4-aza-1-azonia bicyclo[2.2.2]octane chloride and trimethylsilyl cyanide is reported. The scope of the method is demonstrated with 30 examples. The reaction mechanism research indicates that the three-component reaction would be a SN2 reaction. The products exhibit good activities towards advanced synthesis of aqueous soluble acyl-CoA: cholesterol O-acyltransferase-1 (ACAT-1) inhibitors. Our work is superior as it uses less-odor disulfides as carbon sources and EtOH as solvent in a water and dioxygen insensitive reaction system, followed by a simple purification process.

Crystal Structure of Bis(1-butyl-1-methypyrrolidinium) Perthiodicarbonate Complex

Bis(1-butyl-1-methypyrrolidinium) perthiodicarbonate was obtained by the reaction of carbon disulfide with 1-butyl-1-methypyrrolidinium acetate ([BmPyrro][Ac]) in the liquid phase. Structural characterization of this original complex was achieved by single-crystal X-ray diffraction (SCXRD) analysis. The asymmetric unit of the title compound, C2S6·2C9H20N, consisted of two crystallographically 1-methyl-1-butyl pyrrolidinium cations and one perthiodicarbonate anion. The complex C2S6·2C9H20N crystallized in the monoclinic space group, C 2/c, and possessed the following cell parameters: a = 16.0970(10) Å, b = 14.7140(9) Å, c = 12.3280(8) Å, α = 90°, β = 112.3730(12)°, γ = 90°, V = 2700.11 Å3, and Z = 8, Z’ = 0.5.

Spectroscopic Characterization and Photochemistry of the Atmospherically Relevant Methanesulfenic Acid.

Methanesulfenic acid, CH3SOH, is a fleeting intermediate in the ·OH-initiated oxidation reactions of dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) in the atmosphere. Herein, we report the characterization and photochemistry of CH3SOH in Ar- and N2-matrices at 10 K. The characterization of CH3SOH with matrix-isolation IR and UV-vis spectroscopy is supported by D and 13C isotope labeling experiments and quantum chemical calculations. In line with the observed absorption at 260 nm for CH3SOH, its photolysis at 254 nm leads to dissociation by yielding the novel water complex H2CS···H2O, which exhibits a five-membered ring structure with intermolecular S···HO and CH···O hydrogen bonding interactions. Upon further irradiation at 193 nm, the H2CS···H2O complex undergoes dehydrogenation to form CS···H2O, which can further convert to HC(O)SH under irradiation at 254 nm. When the photolysis of CH3SOH was performed in an O2-doped Ar-matrix, methanesulfonic acid (MSA, CH3SO3H) was obtained as the oxidation product.

Visible-Light-Driven Multicomponent Reactions for the Versatile Synthesis of Thioamides by Radical Thiocarbamoylation.

Thioamides are widely used structures in pharmaceuticals and agrochemicals, as well as important synthons for the construction of sulfur-containing heterocycles. This report presents a series of visible-light-driven multicomponent reactions of amines, carbon disulfide, and olefins for the mild and versatile synthesis of linear thioamides and cyclic thiolactams. The use of inexpensive and readily available carbon disulfide as the thiocarbonyl source in a radical pathway enables the facile assembly of structurally diverse amine moieties with non-nucleophilic carbon-based reaction partners. Radical thiocarbamoylative cyclization provides a practical protocol that complements traditional approaches to thiolactams relying on deoxythionation. Mechanistic studies reveal that direct photoexcitation of in situ formed dithiocarbamate anions as well as versatile photoinduced electron transfer with diverse electron acceptors are key to the reactions.

Visible‐Light‐Driven Multicomponent Reactions for the Versatile Synthesis of Thioamides by Radical Thiocarbamoylation

Thioamides are widely used structures in pharmaceuticals and agrochemicals, as well as important synthons for the construction of sulfur‐containing heterocycles. This report presents a series of visible‐light‐driven multicomponent reactions of amines, carbon disulfide, and olefins for the mild and versatile synthesis of linear thioamides and cyclic thiolactams. The use of inexpensive and readily available carbon disulfide as the thiocarbonyl source in a radical pathway enables the facile assembly of structurally diverse amine moieties with non‐nucleophilic carbon‐based reaction partners. Radical thiocarbamoylative cyclization provides a practical protocol that complements traditional approaches to thiolactams relying on deoxythionation. Mechanistic studies reveal that direct photoexcitation of in situ formed dithiocarbamate anions as well as versatile photoinduced electron transfer with diverse electron acceptors are key to the reactions.

Functionalization of Tetraphosphido Ligands by Heterocumulenes.

Although numerous polyphosphido complexes have been accessed through the transition-metal-mediated activation and functionalization of white phosphorus (P4), the selective functionalization of the resulting polyphosphorus ligands in these compounds remains underdeveloped. In this study, we explore the reactions between cyclotetraphosphido cobalt complexes and heterocumulenes, leading to functionalized P4 ligands. Specifically, the reaction of carbon disulfide (CS2) with [K(18c-6)][(Ar*BIAN)Co(η4-P4)] ([K(18c-6)]1, 18c-6 = [18]crown-6) affords the adduct [K(18c-6)][(Ar*BIAN)Co(η3:η1-P4CS2)] ([K(18c-6)]3), in which CS2 is attached to a single phosphorus atom (Ar* = 2,6-dibenzhydryl-4-isopropylphenyl, BIAN = 1,2-bis(arylimino)acenaphthene diimine). In contrast, the insertion of bis(trimethylsilyl)sulfur diimide S(NSiMe3)2 into a P-P bond of [K(18c-6)]1 yields [K(18c-6)][(Ar*BIAN)Co(η3:η1-P4SN2(SiMe3)2)] (K(18c-6)]4). This salt further reacts with Me3SiCl to form [(Ar*BIAN)Co(η3:η1-P4SN2(SiMe3)3] (5), featuring a rare azatetraphosphole ligand. Moreover, treatment of the previously reported complex [(Ar*BIAN)Co(η3:η1-P4C(O)tBu)] (2) with isothiocyanates results in P-C bond insertion, yielding [(Ar*BIAN)Co(η3:η1-P4C(S)N(R)C(O)tBu)] (6a,b; R = Cy, Ph).

Synthesis, and Spectroscopic Characterization study of some Schiff Bases N, N bis (3-methyl-1,2,4-triazole-5- thione (1,3-methylidene) benzene and N, N bis (3-methyl-1,2,4-triazole-5- thione (1,4- methylidene) benzene

Some of triazole derivatives were synthesized by cyclization reaction, of thiocarbohydrazide was synthesized by reaction of carbon disulfide and aqueous hydrazine, the basic nucleus 4-amino- 3- methyl -1, 2, 4-triazole-5-thione(L) was prepared by reaction of thiocarbohydrazide compound with glacial acetic acid under reflux condition.The compound(L) was subjected to addition reaction with different aldehydes to synthesize Schiff bases N,N bis(3-methyl-1,2,4-triazole-5- thione (1,3-methylidene )benzene (L1) and N, N bis(3-methyl-1,2,4-triazole-5- thione (1,4- methylidene )benzene (L2). The compound (L1),(L2) were confirmed by their melting point,FTIR,U.V-visible ,1HNMR spectra.

4-Fluoro-benzyl (Z)-2-(2-oxoindolin-3-yl-idene)hydrazine-1-carbodi-thio-ate.

The title compound, C16H12FN3OS, a fluorinated di-thio-carbazate imine derivative, was synthesized by the one-pot, multi-component condensation reaction of hydrazine hydrate, carbon di-sulfide, 4-fluoro-benzyl chloride and isatin. The compound demonstrates near-planarity across much of the mol-ecule in the solid state and a Z configuration for the azomethine C=N bond. The Z form is further stabilized by the presence of an intra-molecular N-H⋯O hydrogen bond. In the extended structure, mol-ecules are linked into dimers by N-H⋯O hydrogen bonds and further connected into chains along either [20] or [100] by weak C-H⋯S and C-H⋯F hydrogen bonds, which further link into corrugated sheets and in combination form the overall three-dimensional network.

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2‐Aminobenzothiazoles derivatives have revealed a broad spectrum of biological activities, such as anti‐HIV, anti‐inflammatory, antioxidant, anti‐microbial, anti‐tumour, anti‐infective, and anti‐convulsant activities. A great amount of 2‐aminobenzothiazole derivatives have been applied in drugs for the treatment of human diseases. A convenient approach for the construction of 2‐aminobenzothiazoles via I2‐catalyzed tandem cyclization reaction of amines and carbon disulfide has been developed. More details are discussed in the article by Deng et al. on page 846—852.image

Mechanistic and Kinetic Measurements of Elementary Surface Reactions Using Temperature-Programmed X-ray Photoelectron Spectroscopy.

This paper describes a method by which surface-reaction kinetics can be measured by slowly and precisely ramping up the surface temperature at a constant rate while simultaneously collecting X-ray photoelectron spectra (XPS). This approach results in the collection of a large amount of data over relatively small temperature steps to produce quasi-continuous kinetic data. The method is illustrated for the desorption and reaction of diethyl disulfide (DEDS) on a Au(111) substrate in ultrahigh vacuum, where the results can be compared with previous conventional temperature-programmed desorption (TPD) data from Au(111). Experiments were carried out using a double-pass cylindrical-mirror analyzer with a channeltron detector to demonstrate how this approach can be implemented in a routine, multitechnique vacuum chamber. The approach will be even more effective in a more modern, specialized XPS apparatus with high-transmission hemispherical analyzers with multichannel array detectors, which will enable the spectra of several elements to be measured simultaneously. The results yielded an activation energy for multilayer desorption of DEDS of 41 ± 1 kJ/mol, with a pre-exponential factor of 8 ± 7 × 1012 s-1, an activation energy of 53 ± 6 kJ/mol and pre-exponential factor of 9 ± 8 × 1013 s-1 for monolayer desorption and an activation energy of 90 ± 6 kJ/mol with a prefactor of 1.0 ± 0.3 × 1015 s-1 for the reaction of adsorbed ethyl thiolate species to adsorbed DEDS. While these results were collected for a system for which the kinetic data could have been obtained using conventional TPD, this method can be more usefully applied to those surface reaction processes that do not rely on the formation of desorption products. This system, having been previously studied by TPD, facilitates a comparison with results obtained by conventional methods.

Metal‐Free Synthesis of 2‐Aminobenzothiazoles via I2‐Catalyzed Tandem Cyclization Reaction of Amines and Carbon Disulfide

Comprehensive SummaryA convenient approach for the construction of 2‐aminobenzothiazoles via I2‐catalyzed tandem cyclization reaction of amines and carbon disulfide has been developed. The present approach starts from simple and readily available starting materials, affording a series of 2‐aminobenzothiazoles in up to 89% yields under metal‐free conditions. In this work, C—H/N—H functionalization was achieved and multiple C‐hetero bonds were successfully constructed in one pot.

Three-component coupling reaction of white phosphorus, alcohols and diaryl disulfides: a chlorine-free avenue for accessing phosphorothioates

Synthesis of valuable compounds directly from small and simple molecules is an area of great interest in chemical research.

Reactivity of hydrogen sulfide toward organic compounds with sulfur-sulfur bonds

The presence of organic molecules containing sulfur-sulfur bonds was documented in the water columns and sediments of the natural aquatic systems as well as in fossil fuels. These compounds range from small molecules of volatile organic compounds to polysulfide cross-linked macromolecules in the sediments. While processes leading to formation of these compounds were intensively studied during the last decades, kinetics and mechanisms of reactions which lead to their decomposition are poorly understood. In this work, the kinetics and products of the reactions of dimethyl disulfide, dimethyl trisulfide, and cyclic polysulfide lenthionine (1,2,3,5,6-pentathiepane) with hydrogen sulfide at the environmental pH and temperature ranges were studied. It was shown that at pH ≥ 5, the reaction of bisulfide anion (HS–) rather than that of hydrogen sulfide controls the overall reaction rates. The activation energy and the order of the reaction with respect to bisulfide anion is dimethyl disulfide– < dimethyl trisulfide < lenthionine, while the order of the reaction with respect to organosulfur compounds is lenthionine < dimethyl trisulfide < dimethyl disulfide. The obtained results suggest that bisulfide anion is responsible for fast decomposition of organosulfur compounds in aphotic natural aquatic systems. This observation leads to the conclusion that sulfurization of sedimentary organic matter during the early diagenesis is not an unidirectional but a dynamic process, and concentrations of organic compounds with sulfur-sulfur bonds are controlled by the polysulfide to sulfide sulfur concentrations ratio in the sedimentary pore waters. In addition, the cyclic polysulfides were shown to be more stable than their linear analogs that results in preferential preservation of these compounds during the maturation process.

"Alkene-to-Alkene" Difunctionalization of Enaminones for the Synthesis of Polyfunctionalized Alkenes by Transition-Metal-Free C-H and C-N Bond Transformation.

The three-component reactions of enaminones, disulfides, and alcohols for the synthesis of polyfunctionalized alkenes have been realized via the C-H and C-N bond transformation on enaminones. The reactions proceed in a novel "alkene-to-alkene" difunctionalization mode without using any transition metal. The application of the alkene products in the synthesis of divergent sulfenyl heteroaryls, including sulfenylated pyrazoles, pyrimidines, and isoxazoles, via simple annulation has also been verified.

Criegee Intermediate-Mediated Oxidation of Dimethyl Disulfide: Effect of Formic Acid and Its Atmospheric Relevance.

The oxidation-reduction reactions of disulfides are important in both chemistry and biology. Dimethyl disulfide (DMDS), the smallest reduced sulfur species with a disulfide bond, is emitted in significant quantities from natural sources and contributes to the formation of aerosols and hazardous haze. Although atmospheric removal of DMDS via the reactions with OH or NO3 radicals and photolysis is known, the reactions of DMDS with other atmospheric oxidants are yet to be explored. Herein, using quantum chemical calculations, we explored the reactions of DMDS with CH2OO (formaldehyde oxide) and other methyl-substituted Criegee intermediates. The various reaction pathways evaluated were found to have positive energy barriers. However, in the presence of formic acid, a direct oxygen-transfer pathway leading to the corresponding sulfoxide (CH3SS(O)CH3) was found to proceed through a submerged transition state below the separated reactants. Calculations for the methyl-substituted Criegee intermediates, particularly for anti-CH3CHOO, show a significant increase in the rate of the direct oxygen-transfer reaction when catalyzed by formic acid. The presence of formic acid also alters the mechanism and reduces the enthalpic barrier of a second pathway, forming thioformaldehyde and hydroperoxide without any rate enhancement. Our data indicated that, although Criegee intermediates are unlikely to be an important atmospheric sink of DMDS under normal conditions, in regions rich in DMDS and formic acid, the formic acid-catalyzed Criegee intermediate-mediated oxidation of DMDS via the direct oxygen-transfer pathway could lead to organic sulfur compounds contributing to atmospheric aerosol.

Stimuli-Responsive Codelivery System Self-Assembled from in Situ Dynamic Covalent Reaction of Macrocyclic Disulfides for Cancer Magnetic Resonance Imaging and Chemotherapy.

Supramolecular self-assembly has gained increasing attention to construct multicomponent drug delivery systems for cancer diagnosis and therapy. Despite that these self-assembled nanosystems present surprising properties beyond that of each subcomponent, the spontaneous nature of co-self-assembly causes significant difficulties in control of the synthesis process and consequently leads to unsatisfactory influences in downstream applications. Hence, we utlized an in situ dynamic covalent reaction based on thiol-disulfide exchange to slowly produce disulfide macrocycles, which subsequently triggered the co-self-assembly of an anticancer drug (doxorubicin, DOX) and a magnetic resonance imaging (MRI) contrast agent of ultrasmall iron oxide nanoparticles (IO NPs). It showed concentration regulation of macrocyclic disulfides, DOX, and IO NPs by a dynamic covalent self-assembly (DCS) strategy, resulting in a stable codelivery nanosystem with high drug loading efficiency of 37.36%. More importantly, disulfide macrocycles in the codelivery system could be reduced and broken by glutathione (GSH) in tumor cells, thus leading to disassembly of nanostructures and intellgent release of drugs. These stimuli-responsive performances have been investigated via morphologies and molecular structures, revealing greatly enhanced dual-modal MRI abilities and smart drug release under the trigger of GSH. Moreover, the codelivery system conjugated with a targeting molecule of cyclic Arg-Gly-Asp (cRGD) exhibited significant biocompatibility, MR imaging, and chemotherapeutic anticancer effect in vitro and in vivo. These results indicated that in situ dynamic covalent chemistry enhanced the control over co-self-assembly and paved the way to develop more potential drug delivery systems.

Chemoselective Reduction of α,β-Unsaturated Carbonyl Compounds via a CS2/t-BuOK System: Dimethyl Sulfoxide as a Hydrogen Source.

A novel and practical approach to access saturated ketones from unsaturated ketone derivatives via a CS2/t-BuOK system in dimethyl sulfoxide (DMSO) is reported. The in situ generation of xanthate salt through the reaction of carbon disulfide and potassium tert-butoxide is essential to this transformation. Deuterium-labeling experiments demonstrated that DMSO can act as a hydrogen donor.