822-27-5Relevant academic research and scientific papers
Reactions of sulfur containing phenolic antioxidants for elastomers
Meier, Hansrudolf,Kuenzi, Hanspeter,Knobloch, Gerrit,Rist, Guenther,Szelagiewicz, Martin
, p. 275 - 300 (1999)
Alkyl-hydroxybenzylthioethers are efficient storage and processing stabilizers for elastomers and adhesives. Especially alkyl-(2-hydroxybenzyl)thioethers represent an intramolecular combination of a primary and secondary antioxidant, i.e. a phenolic and a thioether moiety in an optimized spatial arrangement. The mechanism of their intramolecular synergism was investigated. The best overall stabilizers are 2,4-bis(alkylthiomethyl)-6-methylphenols, e.g. AOI, in contrast to 2,6-dialkyl-4-alkylthiomethylphenols(B), 4-alkyl-2,6-bis(alkylthiomethyl)phenols C.
Regioselective functionalization of gem-bis(trifluoromethylated) alkanols
Akhrem, Irena S.,Avetisyan, Dzhul'etta V.,Afanas'eva, Lyudmila V.,Tyutyunov, Andrey A.,Artyushin, Oleg I.,Kagramanov, Nikolai D.
, p. 651 - 652 (2018)
One-pot functionalization of sp3 C–H bond in 1,1,1-trifluoro-2-(trifluoromethyl)decan-2-ol with CO and nucleophiles under the action of superelectrophilic complex CBr4·2 AlBr3 affords products of neo-structure and remote functionalities.
Palladium-Catalyzed Carbonylative Synthesis of Aryl Selenoesters Using Formic Acid as an Ex Situ CO Source
Yano De Albuquerque, Danilo,Teixeira, Wystan K. O.,Sacramento, Manoela Do,Alves, Diego,Santi, Claudio,Schwab, Ricardo S.
supporting information, p. 595 - 605 (2022/01/12)
A new catalytic protocol for the synthesis of selenoesters from aryl iodides and diaryl diselenides has been developed, where formic acid was employed as an efficient, low-cost, and safe substitute for toxic and gaseous CO. This protocol presents a high functional group tolerance, providing access to a large family of selenoesters in high yields (up to 97%) while operating under mild reaction conditions, and avoids the use of selenol which is difficult to manipulate, easily oxidizes, and has a bad odor. Additionally, this method can be efficiently extended to the synthesis of thioesters with moderate-to-excellent yields, by employing for the first time diorganyl disulfides as precursors.
Ashless and non-corrosive disulfide compounds as excellent extreme pressure additives in naphthenic oil
Ching Juan, Joon,Ghaffari Khaligh, Nader,Heidelberg, Thorsten,Jiang, Xuefeng,Ling Ong, Chiu
, (2022/02/05)
Medium chain chlorinated paraffin (MCCP) and zinc dialkyl dithiophosphate (ZDDP) are widely used as extreme pressure (EP) additives in metalworking fluids (MWFs). Currently, sulfur-based EP additives are found to be more environmentally friendly and biodegradable. Although naphthenic base oil (NBO) is suitable to be used in MWFs due to its low pour point and better emulsified ability, there is a lack of study on the sulfur additives in this type of oil. In this study, two organo disulfides compounds namely dibenzyl disulfide (DBDS) and dioctyl disulfide (DODS) have been synthesized as EP additives. These DBDS and DODS demonstrate an excellent EP performance, non-corrosive, ashless, and good anti-wear (AW) properties in NBO. The DBDS shows 1961 N (EP value) and 6 mm2 (AW scar area) in NBO, which is superior to DODS, MCCP and ZDDP. This is due to the formation of sulfur-based tribofilm on the interface that acts as a protective sulfur layer thus, enhancing the property of EP.
Practical and efficient recyclable oxidative system for the preparation of symmetrical disulfides under aerobic conditions
Ling, Ong Chiu,Heidelberg, Thorsten,Ching, Juan Joon,Khaligh, Nader Ghaffari
, p. 281 - 294 (2020/12/13)
An efficient and practical oxidative coupling of thiols to symmetrical disulfides is developed at room temperature under aerobic conditions. The commercially available sodium methoxide solution 30 wt. % in methanol together with the air was used as a retrievable promoter system and green oxidant, respectively, for the preparation of symmetrical disulfides. The desired products were obtained in good to high yields by an economical procedure. No overoxidation of the symmetrical disulfides was observed, and various functional groups were well tolerated in the current protocol. Moreover, the new reagent reduces the generation of hazardous waste due to its high reusability. The reaction proceeded in the absence of light, and it was not inhibited by TEMPO. Also, the low yield of TEMPO-benzyl thiol adduct was detected under these conditions. Based on our experiments, a possible mechanism was proposed in the absence and presence of TEMPO.
Green Aerobic Oxidation of Thiols to Disulfides by Flavin-Iodine Coupled Organocatalysis
Iida, Hiroki,Kozako, Ryo,Oka, Marina
supporting information, p. 1227 - 1230 (2021/06/21)
Coupled catalysis using a riboflavin-derived organocatalyst and molecular iodine successfully promoted the aerobic oxidation of thiols to disulfides under metal-free mild conditions. The activation of molecular oxygen occurred smoothly at room temperature through the transfer of electrons from the iodine catalyst to the biomimetic flavin catalyst, forming the basis for a green oxidative synthesis of disulfides from thiols.
Preparation method of symmetric disulfide bond-containing compound
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Paragraph 0020; 0042-0044, (2021/11/21)
The method comprises the following steps: adding a raw material and an oxidant to a reaction bottle containing a solvent; reacting 23W - 85W under the irradiation of 12 - 24h energy-saving lamps; and purifying the reaction product to obtain symmetrical disulfide bond-containing compounds. The raw material is mercaptan or thiophenol. The oxidizing agent is trichlorobromomethane, and the solvent is tetrahydrofuran. The method has the advantages of simple operation, high yield (70 - 90%), wide applicability, cheap and easily available raw materials, and provides a better way for the synthesis and production of symmetrical disulfide bond-containing compounds.
Visible-light-responsive lanthanide coordination polymers for highly efficient photocatalytic aerobic oxidation of amines and thiols
An, Shuyi,Guo, Zhifen,Liu, Xin,Che, Yan,Xing, Hongzhu,Chen, Peng
, p. 15767 - 15775 (2021/09/22)
Development of visible-light-induced photocatalytic reactions using molecular oxygen as the terminal oxidant is intriguing in view of the current environmental and energy issues. We report herein the synthesis and characterization of a series of novel pho
Silylating Disulfides and Thiols with Hydrosilicones Catalyzed by B(C6F5)3
Brook, Michael A.,Liao, Mengchen,Zheng, Sijia
supporting information, p. 2694 - 2700 (2021/06/25)
Hydrosilanes and silicones, catalyzed with B(C6F5)3, may be used to silylate thiols or cleave disulfides giving silyl thio ethers. Alcohols were found to react faster than thiols or disulfides, while alkoxysilanes (the Piers-Rubinsztajn reaction) were slower such that the overall order of reactivity was found to be HO>HS>SS>SiOEt. The resulting silane and silicone-protected thio ethers produced from the sulfur-based functional groups could be cleaved to thiols using alcohols or mild acid with rates that depend on the steric bulk of the siloxane.
Concise and Additive-Free Click Reactions between Amines and CF3SO3CF3
Song, Hai-Xia,Han, Zhou-Zhou,Zhang, Cheng-Pan
supporting information, p. 10907 - 10912 (2019/08/02)
Trifluoromethyl trifluoromethanesulfonate has proved to be an excellent reservoir of difluorophosgene and a promising click ligation for amines in the preparation of urea derivatives, heterocycles, and carbamoyl fluorides under metal- and additive-free conditions. The reactions are rapid, efficient, selective, and versatile, and can be performed in benign solvents, giving products in excellent yields with minimal efforts for purification. The characteristics of the reactions meet the requirements of a click reaction. The use of trifluoromethyl trifluoromethanesulfonate as a click reagent is advantageous over other “CO” sources (e.g., TsOCF3, PhCO2CF3, CsOCF3, AgOCF3, and triphosgene) because this reagent is readily accessible; easy to scale up; and highly reactive, even under metal- and additive-free conditions. It is anticipated that CF3SO3CF3 will be increasingly as important as SO2F2 as a click agent in future drug design and development.
