1879-16-9Relevant articles and documents
Alkaline oxidation by perpropionic acid of aryl-methyl sulfoxide formation. Experimental studies and theories of nucleophilic oxidation of p-substituted thioanisole by perpropionate anion in micellar medium
Lion, Claude,Da Conceicao, Louis,Hecquet, Gerard,Pralus, Christian,Schirmann, Jean-Pierre,Requieme, Benoit
, p. 1131 - 1152 (2004)
The reaction of perpropionic acid CH3CH3CO 3H (1) with thioanisole (4) and p-substituted thioanisoles [p-methoxy (2), p-methyl (3), p-bromo (5), and p-nitro (6)] in stoechiometric proportion has been carried out in micellar medium (cetyl trimethyl ammonium chloride, CTACl). Studies of the influence of the pH, the temperature and the substitution of the thioanisole, provide a better understanding of the sulfoxides (2a-6a) formation. Ab initio calculations have been achieved and the oxidation reaction has been studied in detail in aqueous medium (pH = 11).
On the mechanism of photocatalytic reactions with eosin y
Majek, Majek,Filace, Fabiana,Von Wangelin, Axel Jacobi
, p. 981 - 989 (2014)
A combined spectroscopic, synthetic, and apparative study has allowed a more detailed mechanistic rationalization of several recently reported eosin Y-catalyzed aromatic substitutions at arenediazonium salts. The operation of rapid acid-base equilibria, direct photolysis pathways, and radical chain reactions has been discussed on the basis of pH, solvent polarity, lamp type, absorption properties, and quantum yields. Determination of the latter proved to be an especially valuable tool for the distinction between radical chain and photocatalytic reactions. 2014 Majek et al; licensee Beilstein-Institut.
Catalytic Chemoselective Sulfimidation with an Electrophilic [CoIII(TAML)]?-Nitrene Radical Complex**
van Leest, Nicolaas P.,van der Vlugt, Jarl Ivar,de Bruin, Bas
supporting information, p. 371 - 378 (2020/12/01)
The cobalt species PPh4[CoIII(TAMLred)] is a competent and stable catalyst for the sulfimidation of (aryl)(alkyl)-substituted sulfides with iminoiodinanes, reaching turnover numbers up to 900 and turnover frequencies of 640 min?1 under mild and aerobic conditions. The sulfimidation proceeds in a highly chemoselective manner, even in the presence of alkenes or weak C?H bonds, as supported by inter- and intramolecular competition experiments. Functionalization of the sulfide substituent with various electron-donating and electron-withdrawing arenes and several alkyl, benzyl and vinyl fragments is tolerated, with up to quantitative product yields. Sulfimidation of phenyl allyl sulfide led to [2,3]-sigmatropic rearrangement of the initially formed sulfimide species to afford the corresponding N-allyl-S-phenyl-thiohydroxylamines as attractive products. Mechanistic studies suggest that the actual nitrene transfer to the sulfide proceeds via (previously characterized) electrophilic nitrene radical intermediates that afford the sulfimide products via electronically asynchronous transition states, in which SET from the sulfide to the nitrene radical complex precedes N?S bond formation in a single concerted process.
Scalable electrochemical reduction of sulfoxides to sulfides
Kong, Zhenshuo,Pan, Chao,Li, Ming,Wen, Lirong,Guo, Weisi
supporting information, p. 2773 - 2777 (2021/04/21)
A scalable reduction of sulfoxides to sulfides in a sustainable way remains an unmet challenge. This report discloses an electrochemical reduction of sulfoxides on a large scale (>10 g) under mild reaction conditions. Sulfoxides are activated using a substoichiometric amount of the Lewis acid AlCl3, which could be regeneratedviaa combination of inexpensive aluminum anode with chloride anion. This deoxygenation process features a broad substrate scope, including acid-labile substrates and drug molecules.
N-bromosuccinimide/HCl mediated reduction of sulfoxides to sulfides
Wang, Jianqiang,Shi, Fangmin,Dai, Dongyan,Xiong, Liping,Yang, Yongpo
supporting information, p. 439 - 443 (2021/02/03)
An efficient reduction of sulfoxides to sulfides mediated by N-bromosuccinimide (NBS)/HCl system has been developed. This protocol shows good functional group compatibility as well as broad substrates scope with operational simplicity.
Aryl or heteroaryl methoxylation reaction method
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Paragraph 0120-0126, (2021/11/21)
The invention discloses an aryl or heteroaryl methoxylation reaction method. The method comprises the following steps: preparing a substrate. The coupling agent, ligand, solvent, catalyst and base are mixed homogeneously in an inert gas to give the aryl or heteroaryl methoxy compounds. Compared with a methoxylation reaction method in the prior art, the method has the advantages that the reaction system conditions are mild, the usage amount of the catalyst and the ligand is low to 5% of the amount of the substrate material, and the catalytic efficiency is improved. The method has better compatibility to different substrate expansion and discovery of aryl halides or heteroaryl halides with different functional groups. The yield of aryl or heteroaryl methoxy compounds prepared by the method disclosed by the invention is 36% - 89%.
Production of Alkyl Aryl Sulfides from Aromatic Disulfides and Alkyl Carboxylates via a Disilathiane–Disulfide Interchange Reaction
Nakajima, Takumi,Takano, Ken,Maeda, Hiromu,Ogiwara, Yohei,Sakai, Norio
supporting information, p. 4103 - 4107 (2021/11/10)
The results of this study show that disilathiane is an effective mediator in the synthesis of alkyl aryl sulfides with disulfides and alkyl carboxylates. Mechanistic studies suggest that disilathiane promotes cleavage of the sulfur–sulfur bond of disulfides to generate thiosilane as a key intermediate. Diselenides were also applicable to this transformation to produce the corresponding selenides.
Copper-Catalyzed Methoxylation of Aryl Bromides with 9-BBN-OMe
Li, Chen,Song, Zhi-Qiang,Wang, Dong-Hui,Wang, Jing-Ru
supporting information, p. 8450 - 8454 (2021/11/17)
A Cu-catalyzed cross-coupling reaction between aryl bromides and 9-BBN-OMe to provide aryl methyl ethers under mild conditions is reported. The oxalamide ligand BHMPO plays a key role in the transformation. Various functional groups on bromobenzenes are well tolerated, providing the desired anisole products in moderate to high yields.
Mechanistic Investigation of a Synthetic Route to Biaryls by the Sigmatropic Rearrangement of Arylsulfonium Species
Yanagi, Tomoyuki,Yorimitsu, Hideki
supporting information, p. 13450 - 13456 (2021/08/23)
A comprehensive mechanistic investigation was conducted on the coupling reaction of aryl sulfoxides with phenols by using trifluoroacetic anhydride to yield biaryls. NMR experiments revealed that our previously proposed mechanism, which consists of a cascade of an interrupted Pummerer reaction and a rate-determining [3,3] sigmatropic rearrangement, is reasonable. The electronic effects of the substrates were also evaluated to elucidate the nature of the rearrangement step. Based on experimental observations and theoretical calculations, we conclude that the rearrangement is highly asynchronous and stepwise rather than concerted when electron-rich phenols are employed for the reaction.
Nickel-Catalyzed Reversible Functional Group Metathesis between Aryl Nitriles and Aryl Thioethers
Delcaillau, Tristan,Boehm, Philip,Morandi, Bill
supporting information, p. 3723 - 3728 (2021/04/07)
We describe a new functional group metathesis between aryl nitriles and aryl thioethers. The catalytic system nickel/dcype is essential to achieve this fully reversible transformation in good to excellent yields. Furthermore, the cyanide- and thiol-free reaction shows high functional group tolerance and great efficiency for the late-stage derivatization of commercial molecules. Finally, synthetic applications demonstrate its versatility and utility in multistep synthesis.