A new reagent for the efficient synthesis of disulfides from alkyl halides

Benzyltriethylammonium tetracosathioheptamolybdate [(C₆H₅CH₂N(Et)₃)₆Mo₇S₂₄] has been found to be a superior sulfur transfer reagent for the conversion of alkyl halides to the corresponding disulfides in excellent yields under very mild reaction conditions.     

The rapid and efficient synthesis of disulfides from alkyl and acyl halides

Various symmetrical dialkyl and diacyl disulfides are prepared easily in high yields from the corresponding alkyl and acyl halides under mild and nonaqueous conditions using N,N′-dibutyl-N,N,N′,N′-tetramethyl-ethylenediammonium tetrahydroborate (BTMETB) or N,N′-dibenzyl-N,N,N′,N′-tetramethylethylenediammonium tetrahydroborate (BZTMETB) and elemental sulfur. The quaternary diammonium borohydrides were easily prepared by treatment of the corresponding quaternary diammonium chloride or bromide with alkaline solution of sodium borohydride at room temperature. Correspondence: Mahmood Tajbakhsh, Department of Chemistry, Mazandaran University, Babolsar, Iran.     

The rapid and efficient synthesis of disulfides from alkyl and acyl halides

Various symmetrical dialkyl and diacyl disulfides are prepared easily in high yields from the corresponding alkyl and acyl halides under mild and nonaqueous conditions using N,N′-dibutyl-N,N,N′,N′-tetramethyl-ethylenediammonium tetrahydroborate (BTMETB) or N,N′-dibenzyl-N,N,N′,N′-tetramethylethylenediammonium tetrahydroborate (BZTMETB) and elemental sulfur. The quaternary diammonium borohydrides were easily prepared by treatment of the corresponding quaternary diammonium chloride or bromide with alkaline solution of sodium borohydride at room temperature.     

A novel copper-catalyzed,one-pot synthesis of symmetric organic disulfides from alkyl and aryl halides: potassium 5-methyl-1,3,4-oxadiazole-2-thiolate as a novel sulfur transfer reagent

A new method is reported for the synthesis of symmetric diaryl and dialkyl disulfides from aryl and alkyl halides in the presence of copper using potassium 5-methyl-1,3,4-oxadiazole-2-thiolate as the base, ligand, and sulfur-transfer reagent.     

Palladium-catalyzed C-O bond formation: direct synthesis of phenols and aryl/alkyl ethers from activated aryl halides

A simple and efficient palladium-catalyzed carbon-oxygen bond formation is reported. The palladium-tri-tert-butylphosphine complex was found to be effective in converting haloarenes to corresponding substituted phenols. This methodology offers a direct transformation of aryl halides to phenols, as well as the straightforward application to generate a wide variety of diaryl or alkyl/aryl ethers.     

Rapid and efficient synthesis of symmetrical alkyl disulfides under phase transfer conditions

A one-pot, rapid and general method for the synthesis of symmetrical disulfides based on reaction of sulfur with sodium sulfide in the presence of didecyldimethylammonium bromide (DDAB) as a phase transfer catalyst is reported. Reaction with a variety of alkyl halides, at room temperature, afforded the disulfides in good to excellent isolated yields in a short time.     

A novel and efficient synthesis of alkyl thiocyanates from alkyl halides in water using phase transfer catalysts

1,4-Bis(triphenylphosphonium)-2-butene dichloride(BTPBDC) and 1,4-bis(triphenyl phosphonium)-2-butene dithiocyanate (BTPBDT) were prepared and used as phase-transfer catalysts.Alkyl halides were converted efficiently to the corresponding alkyl thiocyanates under mild reaction conditions in water.No evidence for the formation of isothiocyanates as by-product of the reaction was observed.     

Cu(I) mediated one-pot synthesis of azobenzenes from bis-Boc aryl hydrazines and aryl halides

N,N^′-bis-Boc aryl hydrazines underwent Cu(I) catalyzed couplings with aryl halides to provide N,N^′-bis-Boc diaryl hydrazines. The resulting N,N^′-bis-Boc diaryl hydrazines are readily oxidized to the azobenzenes in the presence of Cu(I) and a base. A prolonged heating of the initial coupling reactions directly provides the corresponding azobenzenes in one pot.     

A facile one-pot synthesis of alkyl aryl sulfides from aryl bromides

A convenient one-pot synthetic method for the formation of alkyl aryl sulfides from various alkyl halides and lithium aryl thiolates that are prepared in situ by direct halogen-lithium exchange is reported. In particular, the method overcomes many of the problems encountered in previous reports; it is very quick, catalyst-free, and does not involve use of unstable aryl thiols.     

Triethylamine-catalyzed one-pot synthesis of trithiocarbonates from carbon disulfide, thiols, and alkyl halides in water

Symmetrical and unsymmetrical trithiocarbonates were prepared by a simple and efficient one-pot reaction of thiols, carbon disulfide, and alkyl halides in the presence of triethylamine in water at room temperature. Correspondence: Barahman Movassagh, Department of Chemistry, K.N. Toosi University of Technology, P.O. Box 16315–1618, Tehran, Iran.     

One-pot synthesis of symmetrical and unsymmetrical aryl sulfides by Pd-catalyzed couplings of aryl halides and thioacetates

Aryl sulfides were obtained from the coupling reaction of S-aryl (or S-alkyl) thioacetates and aryl bromides in the presence of palladium catalyst. This reaction method enables the one-pot synthesis of symmetrical and unsymmetrical diaryl sulfides by employing potassium thioacetate with aryl iodides and aryl bromides.     

One-pot efficient synthesis of disulfides from alkyl halides and alkyl tosylates using thiourea and elemental sulfur without contamination by higher polysulfides

An efficient and odorless synthesis of disulfides from alkyl halides using thiourea and elemental sulfur in the presence of sodium carbonate in wet polyethylene glycol (PEG 200) at 40 °C without contamination by higher polysulfides has been developed. This procedure was then extended to preparation of disulfides from alkyl tosylates at 70 °C.     

A novel approach for the synthesis of alkyl and aryl sulfonamides

A novel approach for the synthesis of alkyl and aryl sulfonamides by the reaction of sulfonic acids, isocyanides and water in dichloromethane is reported at ambient temperature in excellent yields within 20 min. To the best of our knowledge this is the first report on the synthesis of this biologically important family using easily available sulfonic acids and isocyanides.     

CuO nanoparticles-catalyzed a novel method to the synthesis of symmetrical diselenides from aryl halides: selenoamide as an organic Se-donor reagent

A new method is reported for the synthesis of symmetrical diaryldiselenides from aryl halides using selenoamide as an organic Se-donor reagent in the presence of copper (II) oxide nanoparticles. CuO nanoparticles were found to be an efficient and inexpensive catalyst for ligand-free C-Se bond formation with a series of symmetrical diaryldiselenides obtained in good to excellent yield.     

A convenient synthesis of aromatic thiols from unactivated aryl halides

Aromatic thiols are obtained in good yields from unactivated aryl halides and excess MeSNa in HMPA.     

Efficient one-pot synthesis of glycosyl disulfides

Methodology for the efficient and facile synthesis of glycosyl disulfides is reported. A one-pot procedure employing mild conditions using diethyl azodicarboxylate is described to synthesise a series of glycosyl disulfides in excellent yields.     

A novel anionic domino process for the synthesis of o-cyanoaryl-methylthio/alkyl/aryl/heteroaryl acetylenes

A novel unexpected anionic domino process involving n-BuLi-induced rearrangement of 3,3-bis(methylthio) or 3-methylthio-3-aryl/heteroaryl/alkyl-o-bromoarylacrylonitriles to o-cyanoarylacetylenes in synthetically useful yields has been reported. The scope and generality of the reaction has been examined, and a possible mechanism has been proposed.     

A high-yielding, one-pot preparation of unsymmetrical glycosyl disulfides using 1-chlorobenzotriazole as an in situ trapping/oxidizing agent

A high-yielding, one-pot methodology for preparing unsymmetrical glycosyl disulfides derived from sugar, alkyl/aryl or cysteine thiols is reported using 1-chlorobenzotriazole (BtCl) as the oxidant. The highlight of the method is the low temperature of coupling (−78 °C) as well as the in situ trapping of the sulfenyl intermediate, which ensures that no homodimer of R¹SH (R¹SSR¹) is formed. The coupling efficiency is independent of sugar type, thiol position in the sugar, sugar-protecting groups, and the various products serve to illustrate the rapid synthetic access to a number of model systems in glycobiology.     

Electrochemical synthesis of ketones from acid chlorides and alkyl and aryl halides catalysed by nickel complexes

The nickel-catalysed electrochemical cross-coupling of acid chlorides and alkyl or aryl halides in acetonitrile affords unsymmetric ketones in good to high yields. The reaction can be performed under very simple and mild conditions in a diaphragmless cell. A zinc rod as the sacrificial anode has been found to be the most efficient.