4262-06-0Relevant articles and documents
Integrated preparation method of 2-mercaptopyridine and 2, 2 '-pyridinium sulfide
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Paragraph 0037-0045, (2021/09/15)
The invention discloses an integrated preparation method of 2-mercaptopyridine and 2, 2 '-pyridinium sulfide, which comprises the steps of adding sulfur, sodium sulfide and a composite catalyst into water serving as a solvent, and uniformly stirring under a heating condition until the sulfur, the sodium sulfide and the composite catalyst are all dissolved; then adding 2-halogenated pyridine, and reacting for 20-30 hours at a reflux temperature, wherein the composite catalytic system is prepared by adding a cocatalyst with the same weight as cesium acetate into cesium acetate; after the reaction is finished, cooling the reaction liquid to the room temperature, then conducting extraction to respectively obtain extraction liquid and raffinate reaction liquid, and enabling the extraction liquid and the raffinate reaction liquid to be subjected to aftertreatment respectively to obtain 2, 2 '-pyridinium sulfide and 2-mercaptopyridine. The method can obtain two main products at the same time, and generation of by-products is reduced.
Promoting Effect of Crystal Water Leading to Catalyst-Free Synthesis of Heteroaryl Thioether from Heteroaryl Chloride, Sodium Thiosulfate Pentahydrate, and Alcohol
Ma, Xiantao,Yu, Jing,Yan, Ran,Yan, Mengli,Xu, Qing
, p. 11294 - 11300 (2019/09/12)
It is observed the crystal water in sodium thiosulfate pentahydrate (Na2S2O3·5H2O) can promote its multicomponent reaction with heteroaryl chlorides and alcohols, providing a facile, green, and specific synthesis of unsymmetrical heteroaryl thioethers via one-step formation of two C-S bonds under catalyst-, additive-, and solvent-free conditions. Mechanistic studies suggest that the crystal water in Na2S2O3·5H2O is crucial in generating the key thiol intermediates and byproduct NaHSO4, which then catalyzes the dehydrative substitution of alcohols with thiols to afford thioethers.
Efficient Generation of C–S Bonds via a By-Product-Promoted Selective Coupling of Alcohols, Organic Halides, and Thiourea
Ma, Xiantao,Yu, Lei,Su, Chenliang,Yang, Yaqi,Li, Huan,Xu, Qing
supporting information, p. 1649 - 1655 (2017/05/29)
A metal- and base-free three-component coupling of alcohols, heteroaryl halides, and thiourea has been developed for direct and selective synthesis of heteroaryl thioethers. This method can be easily scaled up to the gram scale and extended to dialkyl thioethers, heteroaryl selenides, benzothiazoles, and some antimycobacterially-active thioethers. Mechanistic studies revealed that a by-product-promoted in situ C–O activation of alcohols to more reactive alkyl halides and slow release of the thiol and alkyl halide intermediates are the key to the high selectivity and success of the reaction. (Figure presented.).
Use of base control to provide high selectivity between diaryl thioether and diaryl disulfide for C-S coupling reactions of aryl halides and sulfur and a mechanistic study
Chen, Hsing-Ying,Peng, Wei-Te,Lee, Ying-Hsien,Chang, Yu-Lun,Chen, Yen-Jen,Lai, Yi-Chun,Jheng, Nai-Yuan,Chen, Hsuan-Ying
supporting information, p. 5514 - 5522 (2013/11/06)
Previous studies have reported that S-arylation produces diaryl disulfide when the precursors include sulfur powder and aryl halide using CuI as the catalyst. However, our research has revealed that the use of different bases in the above S-arylation process results in the coproduction of diarylsulfane and diaryldisulfane. In addition, we have demonstrated that the ratio of the two products can be controlled by selecting the alkalinity of the bases. 1H NMR spectra showed that diaryldisulfane was the first product, which became the reagent in a reaction with aryl halide to form diarylsulfane through CuI catalysis. Various aryl halides were tested to enhance the selectivity between diarylsulfane and diaryldisulfane using various different bases, leading to the following principles. A weak base, such as metal carbonate or acetate, results in the production of only diaryldisulfane; a strong base, such as metal hydroxide, results in the production of both diaryldisulfane and diarylsulfane. According to DFT calculations, hydroxide ions, which were exchanged for iodide and bonded with Cu, affected Cu electrons more strongly to reduce diaryl disulfide.
One-Pot Two-Step Synthesis of Aryl Sulfur Compounds by Photoinduced Reactions of Thiourea Anion with Aryl Halides
Argueello, Juan E.,Schmidt, Luciana C.,Penenory, Alicia B.
, p. 4133 - 4136 (2007/10/03)
(Equation presented) The photoinduced reactions of aryl halides with the thiourea anion afford arene thiolate ions in DMSO. These species without isolation, and by a subsequent aliphatic nucleophilic substitution, S RN1 reaction, oxidation, or protonation, yield aryl methyl sulfides, diaryl sulfides, diaryl disulfides, and aryl thiols with good yields (50-80%). This is a simple and convenient approach which involves the use of the commercially available and inexpensive thiourea in a one-pot two-step process for the synthesis of aromatic sulfur compounds.