952-97-6Relevant academic research and scientific papers
A cautionary note on the use of p-nitrobenzenesulfonamides as protecting groups
Wuts,Northuis
, p. 3889 - 3890 (1998)
The cleavage of p-nitrobonzenesulfonamides using thiolate was found to give poor regioselectivity. Cleavage requires addition of thiolate at the sulfonamide carbon, but some addition occurs at the nitro carbon resulting in simple displacement of the nitro group rather than sulfonamide cleavage. The side reaction is most prevalent with cyclic amines and steric effects play only a limited role. This lack of regioselectivity is not observed for o- nitrobenzenesulfonamides.
Modulation of photochemical oxidation of thioethers to sulfoxides or sulfones using an aromatic ketone as the photocatalyst
Zhao, Bin,Hammond, Gerald B.,Xu, Bo
supporting information, (2021/09/13)
We have developed an eco-friendly and chemo-selective photocatalytic synthesis of sulfoxides or sulfones via oxidation of sulfides (thioethers) at ambient temperature using air or O2 as the oxidant. An inexpensive thioxanthone was used as the photocatalyst. Our method offers excellent chemical yields and good functional group tolerance. The hydrogen bonding between hexafluoro-2-propanol (HFIP) and sulfoxides may play an important role in minimizing the over-oxidization of sulfoxides.
Synthesis of thioethers, arenes and arylated benzoxazoles by transformation of the C(aryl)-C bond of aryl alcohols
Chen, Bingfeng,Han, Buxing,Liu, Mingyang,Meng, Qinglei,Song, Jinliang,Zhang, Pei,Zhang, Zhanrong
, p. 7634 - 7640 (2020/08/14)
Transformation of aryl alcohols into high-value functionalized aromatic compounds by selective cleavage and functionalization of the C(aryl)-C(OH) bond is of crucial importance, but very challenging by far. Herein, for the first time, we report a novel and versatile strategy for activation and functionalization of C(aryl)-C(OH) bonds by the cooperation of oxygenation and decarboxylative functionalization. A diverse range of aryl alcohol substrates were employed as arylation reagents via the cleavage of C(aryl)-C(OH) bonds and effectively converted into corresponding thioether, arene, and arylated benzoxazole products in excellent yields, in a Cu based catalytic system using O2 as the oxidant. This study offers a new way for aryl alcohol conversion and potentially offers a new opportunity to produce high-value functionalized aromatics from renewable feedstocks such as lignin which features abundant C(aryl)-C(OH) bonds in its linkages.
Palladium complex containing meta-position carborane triazole ligand and preparation method and application of palladium complex
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Paragraph 0041-0043, (2020/08/07)
The invention relates to a palladium complex containing a meta-position carborane triazole ligand and a preparation method and application of the palladium complex. The palladium complex is prepared by the following steps: (1) dropwise adding an n-BuLi solution into a meta-position carborane m-C2B10H12 solution, carrying out stirring and reacting, then adding 3-propargyl bromide for a reaction again, and after the reaction is finished, carrying out separating to obtain 1,3-dipropargyl meta-carborane; and (2) under the catalytic condition of a catalyst CuI, carrying out a reaction on 1,3-dipropargyl meta-carborane and aryl azide, then adding PdCl2 into a reaction system, continuing the reaction, and after the reaction is finished, carrying out separation to obtain the palladium complex containing the meta-carborane triazole ligand. Compared with the prior art, the preparation method provided by the invention is simple and green; the complex can efficiently catalyze a coupling reaction of mercaptan and halogenated hydrocarbon to synthesize thioether compounds; reaction conditions are mild, substrate universality is good, catalytic efficiency is high, and few byproducts are produced;and the catalyst has high stability and is not sensitive to air and water.
HETEROCYCLIC COMPOUNDS FOR THE TREATMENT OF EPILEPSY
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Paragraph 0134; 0143; 0144, (2020/06/19)
The present invention provides a novel heterocyclic compound represented by Formula [I] and a salt thereof: wherein the symbols are as defined in the specification, which is useful for treating, preventing and/or diagnosing seizure and the like in disease involving epileptic seizure or convulsive seizure (including multiple drug resistant seizure, refractory seizure, acute symptomatic seizure, febrile seizure and status epilepticus), as well as a medical use therefor.
Highly active mesoionic chalcogenone zinc(II) derivatives for C-S cross-coupling reactions
Vaddamanu, Moulali,Prabusankar, Ganesan,Velappan, Kavitha
, p. 129 - 140 (2019/12/26)
The first mesoionic heavier chalcogenones, L1-L3 [L1 = 1-(2-mesitylene)-3-methyl-4-phenyltriazolin-5-selone; L2 = 1-(2-mesitylene)-3-methyl-4-phenyltriazolin-5-thione; L3 = 1-(benzyl)-2-3(methyl)-4-phenyltriazolin-5-selone], were isolated and characterised. Density functional theory was used to obtain insights into the σ donor and π accepting nature of mesoionic chalcogenones. Using these new ligands, a series of the first zinc(ii) mesoionic chalcogenone complexes were isolated. Three mono nuclear zinc(ii) chalcogenone complexes, [(L1)Zn(Cl)2(HOMe)] (1), [(L2)Zn(Cl)2(HOMe)] (3) and [(L2)Zn(Br)2(HOMe)] (4), and two dinuclear zinc complexes, [(L1)Zn(Br)(μ2-Br)]2 (2) and [(L3)Zn(Br)(μ2-Br)]2 (5), containing mesoionic thione and selone ligands were synthesized and characterised. These new complexes 1-5 represent the first structurally characterized mesoionic chalcogenone supported metal derivatives. Furthermore, all zinc complexes were characterized by thermogravimetric analysis and UV-vis spectroscopy. The solid-state structures of all zinc complexes were determined by single-crystal X-ray diffraction. The catalytic activities of the zinc(ii) complexes in thioetherification reactions were investigated without scrubbing of oxygen. The scope of the catalytic reactions was explored with a wide range of thiophenols and aryl halides. The diaryl thioethers were obtained in very good yield under mild conditions. The present protocol furnishes a synthetic route for the C-S cross-coupling of thiophenols and aryl halides without scrubbing oxygen and moisture.
Bimetallic BaMoO4 nanoparticles for the C-S cross-coupling of thiols with haloarenes
Panda, Subhalaxmi,Sahu, Santosh Kumar,Behera, Pradyota Kumar,Panigrahi, Reba,Garnaik, Bamakanta,Rout, Laxmidhar
supporting information, p. 2500 - 2504 (2020/02/20)
We disclosed new bimetallic BaMoO4 nanoparticles for the C-S cross-coupling reaction. The C-S cross-coupling reaction of alkyl/aryl thiols with haloarenes was accomplished with high yields. The reaction has good functional group tolerance and selectivity. This is an efficient protocol for synthesizing the building blocks of pharmaceuticals containing C-S bonds. The catalyst is recyclable. The unactivated bromo- and 4-acetyl fluoro-arenes can well couple to afford thioethers in high yields. The reaction is believed to proceed by oxidative addition and reductive elimination.
CuMoO4 Bimetallic Nanoparticles, An Efficient Catalyst for Room Temperature C?S Cross-Coupling of Thiols and Haloarenes
Panigrahi, Reba,Sahu, Santosh Kumar,Behera, Pradyota Kumar,Panda, Subhalaxmi,Rout, Laxmidhar
, p. 620 - 624 (2019/12/27)
CuII catalyst is less efficient at room temperature for C?S cross-coupling. C?S cross-coupling by CuII catalyst at room temperature is not reported; however, doping of copper with molybdenum metal has been realized here to be more efficient for C?S cross-coupling in comparison to general CuII catalyst. The doped catalyst CuMoO4 nanoparticle is found to be more efficient than copper. The catalyst works under mild conditions without any ligand at room temperature and is recyclable and effective for a wide range of thiols and haloarenes (ArI, ArBr, ArF) from milligram to gram scale. The copper-based bimetallic catalyst is developed and recognized for C?S cross-coupling of haloarenes with alkyl and aryl thiols.
Exploration of the mechanism and scope of the CuI/DABCO catalysed C–S coupling reaction
Thomas, Anns Maria,Sherin,Asha, Sujatha,Manojkumar,Anilkumar, Gopinathan
supporting information, (2019/12/26)
A cost effective and easily available CuI/DABCO catalytic system has been developed for the C–S cross-coupling reaction. This method is extremely useful for the thioetherification of aryl and heteroaryl halides, providing excellent yields and good chemoselectivity. We have also explored the mechanism of the reaction using DFT studies.
Pd (II) immobilized on clinoptilolite as a highly active heterogeneous catalyst for ullmann coupling-type s-arylation of thiols with aryl halides
Alizadeh, Abdollah,Khalilzadeh, Mohammad A.,Alipour, Eskandar,Zareyee, Daryoush
, p. 657 - 666 (2020/08/24)
Background: There are a number of protocols for Ullmann coupling–type S-arylation reactions, many of them suffer from the use of homogenous and often corrosive catalyst, cumbersome workup procedures, and long reaction times. Besides, many of these reagents are expensive and non-recoverable, leading to the generation of a large amount of toxic waste particularly when large-scale applications are considered. Objective: The aim of this study was to prepare a new Pd catalyst bonded on the surface of zeolite as a heterogeneous catalyst. Methods: A heterogeneous palladium catalyst has been prepared by immobilizing Pd ions on Clinoptilolite. This novel developed heterogeneous catalyst was thoroughly examined for Ullmann coupling–type S-arylation reaction using different bases, solvents and 0.003 mg of the catalyst. The structural and morphological characterizations of the catalyst were carried out using XRD, TGA, BET and TEM techniques. Results: Highly efficient heterogeneous palladium catalyst has been developed by immobilizing Pd ions on Clinoptilolite, as one of the most abundant naturally occurring zeolites for Ullmann S-arylation. By using this method, we provide an efficient way to a wide variety of substituted thiolic compounds. Moreover, the catalyst is easily recovered using simple filtration and reused for 5 consecutive runs. Conclusion: In this effort, we developed a new Pd catalyst bonded on the surface of zeolite as a substrate to prepare the heterogeneous catalyst. We demonstrate that this novel catalyst offers reliable and convincing data that may offer a valuable application in further developing the science and technology of Ullmann reaction protocols and allied industries. Additionally, the catalyst was reusable and kept its high activities over a number of cycles.
