Diaryl Sulfides Research Articles

Closing the Loop: Low-Waste Phosphorus Functionalization Enabled by Simple Disulfides.

Useful monophosphorus products are obtained from both white and red phosphorus via a simple strategy involving initial oxidation by aryl disulfides followed by quenching with nucleophiles. Direct transformations of elemental phosphorus are usually very challenging, forcing chemists to instead rely on inefficient and hazardous multi-step methods. However, here they are achieved using inexpensive and easy-to-handle reagents, providing access to diverse P-C, P-N and P-O bonded products in good yields. By isolating the thiolate byproducts of these reactions, a simple, closed loop can be achieved that produces only minimal, benign waste byproducts, in contrast to other direct methods. This closed loop can even be elaborated into a true (electro)catalytic cycle, which is extremely rare in the field of elemental phosphorus functionalization.

Selective Syntheses of Unsymmetrical Diaryl Sulfides Enabled by a Sulfur Dioxide Surrogate as a Divalent Sulfur Source and an Activating Agent

Selective Syntheses of Unsymmetrical Diaryl Sulfides Enabled by a Sulfur Dioxide Surrogate as a Divalent Sulfur Source and an Activating Agent

Arynes Promoted Dehydrosulfurization of Thioamides: Access to Nitriles and Diaryl Sulfides.

An aryne-promoted dehydrosulfurization reaction of thioamides to give nitriles and diaryl sulfides in a one-pot manner is presented. Aromatic, heteroaromatic, and aliphatic natural products and drug-derived nitriles and diaryl sulfides were obtained in good to excellent yields. Especially, selenoamide was also a suitable substrate and produced diaryl selenide and nitrile in high yields. The D-labeled experiments indicated that the protons of thioamides transfer to diaryl sulfides.

Research on synthesis of imidazopyridine-sulfide-aryl derivatives: copper complex immobilized on Fe3O4 nanoparticles catalyzed one-pot C–H bond sulfenylation of imidazopyridines

This research report the development of an eco-friendly, magnetic nanocatalyst, Fe3O4@SiO2-ABHA-CuCl, for the efficient synthesis of diaryl sulfides incorporating imidazo[1,2-a]pyridine scaffolds. The catalyst was successfully prepared by immobilizing CuCl on magnetic Fe3O4 nanoparticles modified with 4-amino-3-hydroxybenzoic acid. Characterization revealed spherical nanoparticles with a size range of 15-30 nm. The catalyst exhibited excellent catalytic activity in promoting C–H bond sulfenylation of imidazopyridines using the green solvent PEG-400. Remarkably, the catalyst demonstrated exceptional recyclability over eight consecutive cycles without significant loss of activity. Comprehensive analysis confirmed the preservation of the catalyst's magnetic properties and structural integrity after repeated use.

Hydrazone-Linked Donor-Acceptor Covalent Organic Polymer as a Heterogeneous Photocatalyst for C-S Bond Formation.

In the realm of solar energy utilization, there is a growing focus on designing and implementing effective photocatalytic systems, for the conversion of solar energy into valuable chemical fuels. The potential of Covalent Organic Polymers (COPs) as photocatalysts for visible-light-driven organic transformation has been widely investigated, positioning them as promising candidates in this field. In the design of COPs, introducing a donor-acceptor arrangement facilitates the transfer of electrons from the donor to the acceptor, creating a charge transfer complex and leading to enhanced conductivity and improved charge separation. Here we present a novel hydrazone-linked covalent organic polymer ETBC-PyHz containing TPE donor and pyridine acceptor. Utilizing this, an efficient method has been developed for an oxidative cross-coupling reaction involving C-S bond formation. This process involves arylhydrazines and arenethiols, and results in the production of unsymmetrical diaryl sulfides via the formation of aryl and thioarene radicals. This conversion holds significant importance because the byproducts produced during the process are nitrogen and water, making it environmentally benign.

FTIR Characterization of Bioactive Functional Groups Present in Crude Extract of Mycoherbicides Produced from Consortium Culture of Rhizosphere Fungal Isolates

ABSTRACT Consortium culture can be a relatively cheap and environment-friendly technology for producing secondary metabolites like pesticides (herbicides). This study produced some metabolites from a consortium culture of fungal isolates obtained from the rhizospheres of Panicum maximum, Ipomoea involucrata and Amaranthus viridis. The isolates from rhizospheres of the above-named plants were co-cultured using Czapek broth and were incubated in an incubator shaker for 28 days. The co-culture combinations were: Aspergillus welwitschiae and Trichoderma hamatum (consortium 1), Aspergillus welwitschiae and Aspergillus aculeatus (consortium 2), and Aspergillus aculeatus and Trichoderma hamatum (consortium 3). Crude extracts from each consortium were characterized using Fourier Transform Infrared Spectroscopy (FTIR). The FTIR results showed that consortium 1 had peak spectra range from 418.57 cm−1 (S–S stretch of aryl disulfides) to 3462.34 cm−1 (alcohol, aliphatic primary amine), consortium 2 had peak spectra range from 420.5 cm−1 (halo compound) to 3456.65 cm−1 (alcohol, aliphatic primary amine) and consortium 3 had peak spectra from 457.14 cm−1 (halo compound) to 3448.84 cm−1 (alcohol, aliphatic primary amine). Some of the compounds produced by the consortia were pesticidal in nature and are hence, considered a potential technology in developing organic pesticides.

Difluorocarbene Enables Modular Synthesis of Difluoroalkylated Bicyclopentanes

A straightforward method for the synthesis of difluoroalkylated bicyclopentanes (BCPs) from [1.1.1]propellane (TCP) through a stepwise procedure has been developed. This process involves nucleophilic addition of organozinc or ArMgBr rea‐gents to TCP, followed by reaction with difluorocarbene to generate BCP substituted difluoroalkylzinc species, which subsequently couple with electrophiles, including allyl/propargyl bromides, (hetero)aryl disulfides, and proton, to provide a wide range of difluoroalkylated BCPs that otherwise are difficult to access through conventional methods. The transformations of the resulting products demonstrate the synthetic utility of this modular synthesis.

Nano-SiO2@nPr@DPyE-Ni: a novel nanocatalyst for the rapid production of symmetric di-aryl sulfides and pyrazolones

Nano-SiO2@nPr@DPyE-Ni: a novel nanocatalyst for the rapid production of symmetric di-aryl sulfides and pyrazolones

Application of hydrazone ligands in Chan−Lam coupling of arylboronic acids and thiols

A Cu/hydrazone catalysis has been applied in the oxidative coupling of arylboronic acids and aromatic thiols for the synthesis of asymmetric diaryl sulfides. The reaction features mild conditions and readily available hydrazone ligand. It works for a wide range of arylboronic acids and thiols with good to excellent yields, exhibiting great potential of such hydrazone ligands in organic synthesis.

Construction and characterization of a magnetic nanoparticle-supported Cu complex: a stable and active nanocatalyst for synthesis of heteroaryl-aryl and di-heteroaryl sulfides.

Diaryl and di-heteroaryl sulfides exist in the structure of many drugs and important biological compounds, also these compounds are well-known in medicinal chemistry due to important biological and pharmaceutical activities. Therefore, the development of novel, ecofriendly and efficient catalytic systems for the preparation of diaryl and di-heteroaryl sulfides is a very attractive and important challenge in organic synthesis. In this attractive methodology, we wish to introduce Fe3O4-supported 3-amino-4-mercaptobenzoic acid copper complex (Fe3O4@AMBA-CuI) nanomaterials as a novel and efficient magnetically recoverable catalyst for the preparation of heteroaryl-aryl and di-heteroaryl sulfides with high yields through reaction of heteroaryl halides with aryl or heteroaryl boronic acids and S8 as the sulfur source under ecofriendly conditions. This catalytic system was very efficient and practical for a diverse range of heteroaryl substrates including benzothiazole, benzoxazole, benzimidazole, oxadiazole, benzofuran, and imidazo[1,2-a]pyridine, because the desired diaryl and di-heteroaryl sulfides were prepared with high yields. The reusability-experiments revealed that the Fe3O4@AMBA-CuI nanocatalyst can be magnetically separated and reused at least six times without a significant decrease in its catalytic activity. VSM and ICP-OES analyses confirmed that despite using the Fe3O4@AMBA-CuI nanocatalyst 6 times, the magnetic properties and stability of the catalyst were still maintained. Although all the obtained heteroaryl-aryl and di-heteroaryl sulfide products are known and previously reported, the synthesis of this number of heteroaryl-aryl and di-heteroaryl sulfides has never been reported by any previouse methods.

Copper-catalyzed alkynyldisulfuration of arynes: efficient access to unsymmetrical disulfides

This article investigates a copper-catalyzed alkynyl disulfuration reaction of arynes formed in situ that generates o-alkynyl aryl disulfides via the formation of one C–C bond and one C–SS bond in one pot.

Immobilized zirconium‐thiouracil complex on MCM‐41 magnetic mesoporous as a recyclable nanocatalyst for carbon‐sulfide bond formation

The synthesis and characterization of MCM‐41 magnetic mesoporous material, which has been modified with zirconium‐thiouracil complex (M‐MCM‐41@TU‐ZrO), has been conducted and thoroughly analyzed using an array of techniques such as X‐ray diffraction (XRD), energy‐dispersive X‐ray spectroscopy (EDX), elemental mapping, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT‐IR), Brunauer‐Emmett‐Teller (BET), inductively coupled plasma‐optical emission spectrometry (ICP‐OES), thermogravimetric analysis (TGA) and vibrating sample magnetometer (VSM). The catalytic performance of M‐MCM‐41@TU‐ZrO was tested in the synthesis of phenyl aryl sulfides through a three‐component coupling reaction of aryl halides/phenolic esters with phenylboronic acid and sulfur powder in the presence of a base in PEG200 at 80–90°C. Also, the synthesis of symmetrical diaryl sulfides using aryl halides and sulfur powder and M‐MCM‐41@TU‐ZrO as a nanocatalyst in dimethyl sulfoxide at 120°C was investigated. A major novelty is that this is the first time that a highly efficient magnetically recyclable zirconium nanocatalyst is used for the synthesis of unsymmetrical diaryl sulfides in the presence of arylboronic acid/S8 system as thiolating agent and phenolic esters as cross‐coupling partners. The other advantages of this method are as follows: (a) the structurally diverse phenyl aryl sulfides have been synthesized in good to high yields in PEG as a green solvent; (b) starting materials, sulfur source, and catalyst are commercially available, cheap, non‐toxic, and chemically stable; and (c) M‐MCM‐41@TU‐ZrO nanocatalyst was easily removed from the reaction mixture using an external magnet and reused numerous times without any significant change in activity.

Photocatalytic Three-Component Reaction for the Synthesis of Multifunctional Diaryl Sulfides.

A photocatalytic three-component reaction of a nitroarene, a thiophenol, and a ketone for the synthesis of multifunctional diaryl sulfides was reported using a nitro group as the nitrogen source and thiophenol as the sulfur source. Thiophenol also serves as a proton donor to reduce nitroarene to arylamine as a key intermediate for the formation of C-N and C-S bonds. Good functional group tolerance and mild reaction conditions make this method have practical synthetic value for diversified multifunctional diaryl sulfides.

Metal-Free Electrochemical Reduction of Disulfides in an Undivided Cell under Mass Transfer Control.

Electroorganic synthesis is generally considered to be a green alternative to conventional redox reactions. Electrochemical reductions, however, are less advantageous in terms of sustainability, as sacrificial metal anodes are often employed. Divided cell operation avoids contact of the reduction products with the anode and allows for convenient solvent oxidation, enabling metal free greener electrochemical reductions. However, the ion exchange membranes required for divided cell operation on a commercial scale are not amenable to organic solvents, which hinders their applicability. Herein, we demonstrate that electrochemical reduction of oxidatively sensitive compounds can be carried out in an undivided cell without sacrificial metal anodes by controlling the mass transport to a small surface area electrode. The concept is showcased by an electrochemical method for the reductive cleavage of aryl disulfides. Fine tuning of the electrode surface area and current density has enabled the preparation of a wide variety of thiols without formation of any oxidation side products. This strategy is anticipated to encourage further research on greener, metal free electrochemical reductions.

Amino Acid Sulfinate Salts as Alkyl Radical Precursors

A general approach to the synthesis of amino acid sulfinate salts from commercially available α-chiral hydroxylated amino acids is reported. These reagents are shown to be valuable precursors to alkyl radicals under mild photochemical oxidation conditions. The photochemically generated amino acid radicals engage readily with alkyl and aryl disulfide radical traps to afford a diverse suite of modified amino acids.

Synthesis of Asymmetric Diaryl Sulfides via HI-Mediated C(sp2)-H Sulfenylation of Arenes with Sodium Sulfinates.

A novel hydroiodic acid-promoted metal-free C(sp2)-H sulfenylation of electron-rich arenes was developed using stable and easy-to-handle sodium sulfinates as sulfur sources. Diverse kinds of asymmetric aryl sulfides were afforded in good yields from various commercially available aromatic substrates under mild conditions. Comprehensive mechanistic experiments demonstrate that RSO2SR and RSSR are the key intermediates responsible for the redox process.

Migrative Thioamination of Aryne Intermediates Generated from o-Iodoaryl Triflates

AbstractMigrative thioamination of aryne intermediates takes place using various o-iodoaryl triflates and sulfilimines. The selective migration realizes the facile synthesis of a broad range of highly functionalized o-thioaminated diaryl sulfides. We succeeded in the ring expansion of cyclic sulfilimines enabling us to prepare eight- and nine-membered organosulfurs from dibenzothiophene- and thianthrene-type sulfilimines, respectively.

A Novel and Efficient Magnetically Recoverable Copper Catalyst for Synthesis of Symmetrical Diaryl Selenides and Sulfides

Diaryl sulfides and selenides are ubiquitous chemical structures found in natural products, synthetic organic semiconductors, agricultural, and various biologically active molecules. Therefore, the development of novel and efficient catalytic systems for the preparation of diaryl sulfides and selenides is an important challenge in organic synthesis. In this paper, we wish to report the construction of a novel and efficient nanomagnetic copper nanocatalyst through the immobilization of Cu(OAc)2 on the surface of magnetic nanoparticles modified with Imine-Thiazole as ligand. The as-fabricated Fe3O4@SiO2-(Imine-Thiazole)-Cu(OAc)2 nanocomposite shown high catalytic activity in the C-Se (83%-98%) and C-S bond formation at 100 °C. To the best of our knowledge, this is the first report on the use of magnetically reusable copper nanocatalyst for the synthesis of diaryl selenides and sulfides via the reaction of triarylbismuthanes with elemental Se or S powder under aerobic conditions. Recycling experiments revealed that the copper nanocatalyst could be easily recovered by a simple magnetic separation and recycled at least eight times without deterioration in catalytic activity.

Production and characterization of Fe3O4@SiO2@TMEDA-Pd as a very effectual interphase catalyst for the rapid preparation of di-aryl sulfides and pyrido-dipyrimidines

Production and characterization of Fe3O4@SiO2@TMEDA-Pd as a very effectual interphase catalyst for the rapid preparation of di-aryl sulfides and pyrido-dipyrimidines

Hemin‐Promoted Direct C−H Thiolation in the Synthesis of Diaryl Sulfides

AbstractDiaryl sulfides are a class of important synthetic chemical units. Herein, we report a new method for direct preparation of diphenyl sulfides using P‐toluenesulfonyl chloride as an effective thiophenyl radical precursor with assistance from Hemin. Various substituted anisoles and benzenesulfonyl chlorides are well tolerated, resulting in moderate to good yields of diaryl sulfides. The potential of the proposed method is validated by good yields obtained in gram scale reactions.