Novel p-arylthio cinnamides as antagonists of leukocyte function-associated antigen-1/intracellular adhesion molecule-1 interaction. 2. Mechanism of inhibition and structure-based improvement of pharmaceutical properties

Regio- and stereoselective syntheses of allylic thioethers under metal free conditions

A metal-free, regio and stereoselective synthesis of allylic thioethers using densely functionalized allyl iodides and aryl/alkyl disulfides as coupling partners, provided the resulting allyl aryl thioethers in 62–92% isolated yields is described.

Carbon–sulfur bond reductive coupling from a platinum(ii) thiolate complex

Complex 1 was reacted with different alkyl halides at room temperature. This reaction proceeded via formation of binuclear intermediate complex 3 and through C–S bond reductive coupling to produce alkyl sulfides and corresponding halide complexes 2.

Functionalized graphene oxide as an efficient adsorbent for CO2 capture and support for heterogeneous catalysis

New functionalized graphene oxide materials IFGO and Cu-IFGO have been synthesized via post-synthetic pathway where IFGO exhibited high CO₂ uptake capacity and Cu-IFGO displayed high catalytic activity in one-pot three component C–S coupling reactions.

Aryl diazonium salt and thioacetamide: a catalyst free, efficient blend of an inexpensive arylating agent with “S” surrogate for sulphide synthesis

Metal free, chemoselective method for C–S, S–S bond formation reactions.

Fe–Cu catalyzed synthesis of symmetrical and unsymmetrical diaryl thioethers using 1,3-benzoxazole-2-thiol as a sulfur surrogate

An efficient Fe–Cu catalyzed approach is herein developed using 1,3-benzoxazole-2-thiol as a thiol surrogate for the synthesis of symmetrical and unsymmetrical diaryl thioethers.

Efficient synthesis of unsymmetrical heteroaryl thioethers and chalcogenides by alkali hydroxide-mediated SNAr reactions of heteroaryl halides and dichalcogenides

An efficient S_NAr reaction of heteroaryl halides and diorganyl dichalcogenides is developed for practical synthesis of the useful unsymmetrical heteroaryl thioethers and chalcogenides.

Regioselective transition metal- and halogen-free direct dithiolation at C(sp3)–H of nitrotoluenes with diaryl disulfides

Here we describe a potassium tert-butoxide-mediated regioselective direct C–S bond formation at the C(sp³)–H position of nitrotoluenes with disulfides in DMSO at room temperature. The developed reaction generated various dithioacetals in good yields. Further, synthesized dithioacetals were transformed into 4-nitrobenzaldehyde and 7-(bis(phenylthio)methyl)-1H-indole.

DFT studies on the mechanism of palladium catalyzed arylthiolation of unactive arene to diaryl sulfide

The cleavage of S–N bond prefers to take place via concerted σ-bond metathesis rather than oxidative addition proposed in experiment.

Novel formazan derivatives containing phenylsulfanyl and carbonyl units: synthesis, optical and electrochemical properties

New phenylsulfanyl and aryl carbonyl containing formazan derivatives 4a–4h and 5a–5h have been developed, and investigated the effect of substituents on their photophysical and electrochemical properties.

Aerobic copper-catalyzed decarboxylative thiolation

A copper-catalyzed decarboxylative thiolation reaction to furnish aryl sulfides using molecular oxygen as the sole oxidant is described.

CuFe2O4 magnetic nanoparticle catalyzed odorless synthesis of sulfides using phenylboronic acid and aryl halides in the presence of S8

The ligand-free synthesis of sulfides is reported in the presence of CuFe₂O₄ as a magnetically reusable nanocatalyst in PEG.

An efficient heterogeneous catalyst (CuO@ARF) for on-water C-S coupling reaction: an application to the synthesis of phenothiazine structural scaffold

Background

Aryl sulfides have significant importance from biological and pharmaceutical aspects. Transition metal-catalyzed carbon-sulfur cross-coupling reaction represents an important tool for the synthesis of sulfides. Among various transition metals, copper salts or oxides have found vast applicability.

Results

A simple procedure for the preparation of poly-ionic amberlite resins embedded with copper oxide nanoparticles (CuO NPs) (denoted as CuO@ARF) has been developed, characterized, and employed for the first time as a heterogeneous ligand-free catalyst for ‘on-water’ C-S cross-coupling reaction. The NPs of CuO with an average size (approximately 2.6 nm), as determined from high resolution transmission electron microscopy (HRTEM) images, are found to be a potentially active, chemoselective, and recyclable catalyst for the preparation of symmetrical and unsymmetrical aryl sulfides. Recycling of the catalyst was performed successfully for five consecutive runs, and apparently no leaching was observed in a hot filtration test. Excellent chemoselectivity between iodo- and bromo-arene has been exploited in step-wise C-S and C-N couplings to synthesize bioactive heterocyclic scaffold phenothiazine.

Conclusions

An efficient method is established for the C-S cross-coupling reaction using heterogeneous catalyst CuO@ARF under ligand-free on-water condition. The catalyst is highly chemoselective among different aryl halides, which has been demonstrated in the synthesis heterocyclic scaffold phenothiazine. Furthermore, it is recyclable for five consecutive runs examined.Graphical abstract

Tridentate Hydroxy-Functionalised MCM-41-Immobilised Copper(I) Complex as an Efficient and Recyclable Catalyst for Coupling of Aryl Iodides with Thiols

The C–S coupling reaction of aryl iodides with thiols was achieved at 110 °C in DMF/dioxane (V/V, 1:9) in the presence of a tridentate hydroxy-functionalised MCM-41-immobilised copper(I) complex [MCM-41-3OH-CuI] with Cs2CO3 as base to afford a variety of diaryl sulfides in good to excellent yields. The MCM-41-3OH-CuI catalyst can be easily recovered by a simple filtration and reused for at least six times without significant loss of activity.

Nickel-catalyzed and benzoic acid-promoted direct sulfenylation of unactivated arenes

A nickel-catalyzed direct sulfenylation of unactivated arenes using removable 2-(pyridine-2-yl)-isopropylamine as a directing group has been developed.

One-pot odorless thia-Michael reaction by copper ferrite nanoparticle-catalyzed reaction of elemental sulfur, aryl halides and electron-deficient alkenes

One-pot CuFe₂O₄ catalyzed reaction of aryl halides or boronic acids with sulfur and electron-deficient alkenes for generation of sulfides.

One-pot three-component synthesis of 3-hydroxy-5,5-dimethyl-2-[phenyl(phenylthio)methyl]cyclohex-2-enone derivatives under ultrasound

3-Hydroxy-5,5-dimethyl-2-[phenyl(phenylthio)methyl]cyclohex-2-enone is synthesized via one-pot three-component reactions of aromatic aldehyde, substituted thiophenol and 5,5-dimethyl-1,3-cyclohexanedione catalyzed by p-dodecylbenzene sulfonic acid (DBSA) under ultrasound. Under ultrasound irradiation the yields are much higher (sometimes substantially, by almost double) and the reaction time decreases substantially, the reaction conditions are milder. This method provides several advantages such as environment friendliness, high yields and simple work-up procedure and the protocol provides a novel alternative for the synthesis of thioether.

Ligand-free Cu-catalyzed odorless synthesis of unsymmetrical sulfides through cross-coupling reaction of aryl/benzyl/alkyl halides with an aryl boronic acid/S8 system as a thiolating agent in PEG

Efficient one-pot, one-step synthesis of unsymmetrical sulfides has been reported under mild reaction conditions with good yields in green solvent.

A facile synthesis and evaluation of new biomolecule-based coumarin–thiazoline hybrids as potent anti-tubercular agents with cytotoxicity, DNA cleavage and X-ray studies

A rapid and high yielding synthesis of coumarin–thiazoline hybrids as potent anti-tubercular agents, along with cytotoxicity, DNA cleavage and X-ray studies, is described.

Silver-mediated thio-acetoxylation and TFA triggered cyclization of amino disulfides with unactivated alkenes: synthesis of 3-aryl/alkyl-1,4-benzothiazines

A protocol for the synthesis of 3-aryl/alkyl-1,4-benzothiazines has been developed, which involves silver-mediated 1,2-thioacetoxylation of an alkene followed by cyclization using TFA.

Iodine-mediated thiolation of phenol/phenylamine derivatives and sodium arylsulfinates in neat water

An efficient and convenient protocol for iodine-mediated thiolation of phenols/phenylamines with sodium benzene-sulfinates in water has been achieved.