Regioselective synthesis of diaryl sulfides by [3+3] cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-dienes

Functionalized and sterically encumbered diaryl sulfides were prepared based on [3+3] cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-dienes.     

Synthesis of diaryl sulfides through CH bond functionalization of arylamides with cobalt salt and elemental sulfur

A cobalt(II)-mediated, highly chemoselective thioarylation reaction of arylamides with elemental sulfur was reported. This reaction led to the formation of various symmetric diaryl sulfides in yields of up to 65% under mild reaction conditions. A cobalt-sulfur radical process was proposed based on preliminary results and mechanistic studies.     

Synthesis of functionalized diaryl sulfides based on regioselective one-pot cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes

Functionalized diaryl sulfides were prepared based on one-pot cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes.     

Copper-catalyzed direct preparation of diaryl sulfides from aryl iodides using potassium thiocyanate as a sulfur transfer reagent

A method for direct preparation of diaryl sulfides from aryl iodides using potassium thiocyanate as a sulfur-transfer agent is reported. A catalyst system comprising of a simple copper salt, tetrabutylammonium bromide as a phase-transfer agent and water as the solvent is used. Microwave heating at 200 °C for 60 min allows for the conversion of a range of aryl iodides to the corresponding diaryl sulfides.     

Direct synthesis of diaryl sulfides by copper-catalyzed coupling of aryl halides with aminothiourea

An efficient and simple protocol of copper-catalyzed C-S bond formation between aryl halides and inexpensive and commercially available aminothiourea is reported.A variety of symmetrical diaryl sulfides can be synthesized in good to excellent yields up to 94%with the advantage of avoiding foul-smelling thiols.     

L-cysteine as sustainable and effective sulfur source in the synthesis of diaryl sulfides and heteroarenethiols

L-cysteine, a natural and essential amino acid, was employed as novel sulfur source in the synthesis of symmetrical diaryl sulfides from a variety of aryl iodides in moderate to excellent yields. A tandem three steps’ reactions including C(sp²)-S bond formation, C(sp³)-S bond cleavage and another C(sp²)-S bond formation were proposed to be involved in this conversion. This protocol was featured by broad substrate scope and good functional group tolerance. In addition, heteroarenes including benzothiazoles and benzoxazoles were successfully converted into the corresponding heteroarenethiols using L-cysteine as C-H mercaptalization reagent.     

Ligand‐free copper‐catalysed direct synthesis of diaryl sulfides and diaryl disulfides in wet poly(ethylene glycol)

An improved protocol has been developed for the one‐pot CuI‐catalysed preparation of symmetric diaryl sulfides from their available aryl halides in the presence of thiourea as sulfur transfer agent and in the absence of both ligand and organic solvent. This catalytic system was also used for the high‐yielding preparation of diaryl disulfides in the presence of C₂Cl₆ as oxidant.     

A concise method for synthesis of diaryl aryl- or alkylphosphonates

A convenient method has been developed to synthesize diaryl arylphosphonates from triaryl phosphites, triethyl phosphite, and aromatic halides. The new method relies on the triethyl phosphite assisted nickel catalyzed Arbuzov reaction and can be applied to synthesize certain diaryl alkylphosphonates without catalysts.     

Copper-catalyzed Ullmann-type synthesis of diaryl ethers assisted by salicylaldimine ligands

A series of salicylaldimine ligands were designed to promote the copper-catalyzed Ullmann cross- coupling reaction. After a screening process, 2-（（2-isopropylphenylimino）methyl）phenol was found to serve as a good supporting ligand for this reaction. Employing this Schiff-base ligand as a new supporting ligand, the copper-catalyzed coupling reactions of aryl bromides and aryl iodides with various phenols successfully proceeded in good yields under mild conditions. Various diaryl ethers were obtained with excellent yields in dioxane in the presence of K3P04 and a catalytic amount of copper（I） salt.     

Design,synthesis and antiproliferative activities of diaryl urea derivatives bearing N-acylhydrazone moiety

A new series of diaryl urea derivatives bearing N-acylhydrazone moiety were designed and synthesized.All the target compounds were evaluated for their antiproliferative activities against human leukemia cell line(HL-60),human lung adenocarcinoma epithelial cell line(A549) and human breast cancer cell line(MDA-MB-231) in vitro by standard MTT assay.The pharmacological results indicated that some compounds exhibited promising antitumor activities.Compound 1j showed the most potent antiproliferative activity against the tested three cell lines with IC values of 0.13 mmol/L,0.7 mmol/L and 0.5 mmol/L,respectively.     

Pd-NHC-catalyzed synthesis of diaryl ketones

With N-hetereocyclic carbene and palladium catalysis, diaryl ketones with a variety of functional groups that span from electron withdrawing to electron donating substitutions can be conveniently synthesized using the corresponding aryl boronic acid and N-acyloxyphthalimide.     

Ullmann diaryl ether synthesis catalyzed by copper (I)/pyridine-functionalized silane

Ullmann-type diaryl ether synthesis was performed under mild conditions in DMF/K₂CO₃ using a pyridine-functionalized silane as a ligand. The products were obtained in good yields. This method tolerates a variety of functional groups and is effective in the synthesis of hindered diaryl ethers and heteroaryl ethers.     

Synthesis of sulfides under solvent- and catalyst-free conditions

Abstract  A simple, highly efficient, and green protocol has been developed for preparation of sulfides from alkyl or aryl thiols and benzyl-, allyl-, t-butyl, and adamantyl halides under solvent- and catalyst-free conditions. Graphical abstract        

Solvent free,palladium catalyzed highly facile synthesis of diaryl disulfides from aryl thiols

An efficient solvent free Pd(pCH₂S)₂dba catalyzed green-chemical strategy for the synthesis of diaryl disulfides from aryl thiols in moderate to excellent yield is reported. Variety of diaryl disulfides were synthesized. The catalyst is recyclable up to four cycles.     

An efficient BINAM-copper(II) catalyzed Ullmann-type synthesis of diaryl ethers

A wide range of diaryl ethers are synthesized from the corresponding aryl iodides and phenols through Ullmann type coupling reactions in the presence of a catalytic amount of easily available BINAM-Cu(OTf)₂ complex under mild reaction conditions. Less reactive aryl bromides have also been shown to react with phenols under identical reaction conditions to give good yields of the diaryl ethers without increasing the reaction temperature and time.     

Phase-controlled synthesis and characterization of nickel sulfides nanorods

Different one-dimensional nickel sulfides, NiS nanorods and Ni₉S₈ nanorods were synthesized in the presence (Route 1) and absence (Route 2) of gas CO₂. X-ray powder diffraction patterns, scanning electron microscopy and transmission electron microscopy images show that the product from Route 1 is NiS nanorods with a diameter of about 50-120 nm, while the product from Route 2 is Ni₉S₈ nanords about 70-200 nm in diameter. A molecular-template-like mechanism was proposed for the one-dimensional structures growth. The products were also investigated by Raman and photoluminescence (PL) spectroscopy.     

Novel C-H functionalization of arenes: palladium-catalyzed synthesis of diaryl sulfides

A novel protocol for the direct arylthiolation of electron-rich arenes is described. Applying arylsulfonyl cyanides in the presence of catalytic amounts of Pd allows for a straightforward synthesis of diaryl sulfides.     

Chemoselective and ligand-free synthesis of diaryl ethers in aqueous medium using recyclable alumina-supported nickel nanoparticles

An economical and eco-compatible ligand-free protocol for the synthesis of diaryl ethers has been developed using easily accessible alumina-supported nickel nanoparticles as a stable recyclable heterogeneous catalyst in aqueous medium along with a surfactant (SDS) and a mild base (K₂CO₃). Various sensitive functional groups like allyl, alkoxycarbonyl, formyl, oxo, chloro, bromo, amine and nitro were tolerated in the aforesaid method. Excellent chemoselectivity was demonstrated through competition experiments.     

Traceless solid-phase synthesis of multiple sulfonamide-containing cyclic sulfides exploiting microwave irradiation

In this Letter, a new synthetic method of sulfonamide-containing cyclic sulfides using a microwave-assisted traceless solid-phase approach is described. Using this new method, many highly pure cyclic sulfides were efficiently synthesized based on intramolecular alkylation of the sulfides followed by elimination of the desired products from the generated sulfonium salts.     

Negishi cross-coupling of organotellurium compounds: synthesis of biaryls, aryl-, and diaryl acetylenes

A functional group tolerant palladium-catalyzed Negishi coupling of diaryl tellurides with organozinc has been developed. This methodology permits efficient preparation of biaryls, aryl acetylenes and diaryl acetylenes in moderate to good yields. A preliminary study to gain further insight into the reaction was performed using in situ ReactIR technology.