95-33-0Relevant articles and documents
Preparation method of rubber vulcanization accelerator CBS
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Paragraph 0059-0108, (2021/05/15)
The invention provides a preparation method of a rubber vulcanization accelerant CBS, and relates to the technical field of rubber vulcanization accelerants. The preparation method comprises the stepsof firstly dissolving 2-mercaptobenzothiazole in an organic solvent,adding a catalyst, fully mixing, and then dropwise adding cyclohexylamine for catalyzed oxidation reactions under a constant temperature and a constant pressure, introducing oxygento maintain the reactions at the constant pressure during the reactions, completing the reactions when the reaction pressure does not change for 30-40minute after the cyclohexylamine is added, and preparing the rubber vulcanization accelerant CBS; the organic solvent can well dissolve the CBS but does not chemically react with the 2-mercaptobenzothiazole and the cyclohexylamine. The preparation methodcan takethe oxygen as an oxidant to oxidize and synthesize the CBS under the effects of the catalyst,the generation of waste water containing nitrosamine carcinogens is eliminated,the cost ofoxidants is reduced, and the preparation method has the advantages of being green, environmentally friendly, energy-saving and economical.
A comprehensive electrochemical study of 2-mercaptobenzoheterocyclic derivatives. Air-assisted electrochemical synthesis of new sulfonamide derivatives
Youseflouei, Nesa,Alizadeh, Saber,Masoudi-Khoram, Mahmood,Nematollahi, Davood,Alizadeh, Hojjat
, (2020/06/05)
In this work, we have introduced a green air-assisted electrochemical method for the synthesis of new sulfonamide derivatives via oxidative coupling of heterocyclic thiols and amines. The synthetic method was designed based on the data collected from electrochemical oxidation of heterocyclic thiols, 2-mercaptobenzoxazole (MBO), 2-mercaptobenzothiazole (MBT) and 2-mercaptobenzimidazole (MBI) in the absence and presence of amines. The electrochemical results indicate that the oxidation of MBO and MBT lead to the formation of the corresponding dimers, which as an intermediate is essential for sulfonamide synthesis. The results also show that, in the time scale of our voltammetric experiments, oxidation of MBI does not lead to dimer formation. Our voltammetric studies suggest that the formed dimer is adsorbed on the electrode surface. The amount and intensity of adsorption depends on the type heterocyclic thiol, solvent, switching potential and solution pH. The mechanism of synthesis of sulfonamide compounds has been established based on the disappearing of the dimer reduction peak in the cyclic voltammogram of MBO in the presence of amines along with increasing the number of electrons transferred in this condition, as well as spectroscopic data of the products. These compounds have been successfully synthesized in water/ethanol mixture solutions in an undivided cell, at carbon rod electrodes, by constant current electrolysis at room temperature. The proposed method does not need to use toxic solvent, metal, catalyst and challenging workups. This method is easy to scale-up and the products have antibacterial activity.
Scalable electrochemical oxidant-and metal-free dehydrogenative coupling of S-H/N-H
Tang, Shanyu,Liu, Yan,Li, Longjia,Ren, Xuanhe,Li, Jiao,Yang, Guanyu,Li, Heng,Yuan, Bingxin
supporting information, p. 1370 - 1374 (2019/02/14)
A practical and scalable electrochemical oxidation of S-H and N-H was developed. This oxidant- and catalyst-free electrochemical process enables S-N bond formation with inexpensive nickel electrodes in an undivided cell. This procedure exhibits broad substrate scopes and good functional-group compatibility. A 50 g scale oxidative coupling augurs well for industrial applications.
