22865-50-5Relevant articles and documents
CuI-catalyzed direct synthesis of diaryl thioethers from aryl boronic acids and arylsulfonyl chlorides
Huang, Keke,Yang, Min,Lai, Xiao-Jing,Hu, Xin,Qiu, Guanyinsheng,Liu, Jin-Biao
, (2019/12/27)
A CuI-catalyzed direct coupling of aryl boronic acids with arylsulfonyl chlorides for the preparation of diaryl thioethers was developed. The reaction is initiated by a PPh3 reduction of the arylsulfonyl chloride, followed by a CuI-catalyzed C–S coupling with an aryl boronic acid. Various arylsulfonyl chlorides can directly serve as a sulfur source in this mild and efficient reaction giving the desired products in moderate to good yields. Moreover, this practical method has also been applied to the thioetherification of aryl iodides and acetylacetones.
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.
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.
