19541-52-7Relevant academic research and scientific papers
Palladium-catalyzed heteroaryl thioethers synthesis overcoming palladium dithiolate resting states inertness: Practical road to sulfones and NH-sulfoximines
Guilbaud, Johan,Labonde, Marine,Selmi, Awatef,Kammoun, Majed,Cattey, Hélène,Pirio, Nadine,Roger, Julien,Hierso, Jean-Cyrille
, p. 52 - 58 (2018/04/11)
We provide efficient synthetic access to heteroaryl sulfones in two-steps using a simple palladium–1,1′-bis[(diphenyl)phosphanyl]ferrocene catalyst to form in high yields variously functionalized heteroaromatic thioethers. Pyridinyl-containing substrates can be subsequently selectively oxidized into sulfones and NH-sulfoximines by using very mild oxidation conditions with a high functional group tolerance. In the palladium-catalyzed C–S coupling of heteroaromatic thiols, reactivity limitation is attached with electron-deficient thiols. We show that this limitation can be resolved by the successful use of 2-bromoheteroarenes in the C–S coupling. We established herein that this choice of heteroaryl electrophilic reagent in palladium-catalyzed C–S bond formation allows overcoming palladium dithiolate out-of-cycle resting state inertness. This was illustrated in the stoichiometric reactivity study of the palladium dithiolate formed from 4-trifluoromethylbenzen-1-thiol –isolated and characterized by multinuclear NMR and XRD– with both 2-chloropyridine and 2-bromopyridine.
Efficient synthesis of unsymmetrical heteroaryl thioethers and chalcogenides by alkali hydroxide-mediated SNAr reactions of heteroaryl halides and dichalcogenides
Ma, Xiantao,Liu, Quan,Jia, Xiaojuan,Su, Chenliang,Xu, Qing
, p. 56930 - 56935 (2016/07/06)
An efficient alkali hydroxide-mediated SNAr reaction of heteroaryl halides has been developed for the practical synthesis of the useful unsymmetrical heteroaryl thioethers and chalcogenides. The usually odorless, easily available, lowly toxic, and easily stored and handled diorganyl dichalcogenides can be used as safer and convenient chalcogen nucleophile precursors and diverse unsymmetrical heteroaryl chalcogenides can be obtained in good to high yields by the method.
Thioetherification of Chloroheteroarenes: A Binuclear Catalyst Promotes Wide Scope and High Functional-Group Tolerance
Platon, Mélanie,Wijaya, Novi,Rampazzi, Vincent,Cui, Luchao,Rousselin, Yoann,Saeys, Mark,Hierso, Jean-Cyrille
, p. 12584 - 12594 (2016/08/25)
A constrained binuclear palladium catalyst system affords selective thioetherification of a wide range of functionalized arenethiols with chloroheteroaromatic partners with the highest turnover numbers (TONs) reported to date and tolerates a large variety of reactive functions. The scope of this system includes the coupling of thiophenols with six- and five-membered 2-chloroheteroarenes (i.e., functionalized pyridine, pyrazine, quinoline, pyrimidine, furane, and thiazole) and 3-bromoheteroarenes (i.e., pyridine and furane). Electron-rich congested thiophenols and fluorinated thiophenols are also suitable partners. The coupling of unprotected amino-2-chloropyridines with thiophenol and the successful employment of synthetically valuable chlorothiophenols are described with the same catalyst system. DFT studies attribute the high performance of this binuclear palladium catalyst to the decreased stability of thiolate-containing resting states. Palladium loading was as low as 0.2 mol %, which is important for industrial application and is a step forward in solving catalyst activation/deactivation problems.
Sulfur-silicon bond activation catalysed by Cl/Br ions: Waste-free synthesis of unsymmetrical thioethers by replacing fluoride catalysis and fluorinated substrates in SNAr reactions
Jia, Xiaojuan,Yu, Lei,Liu, Jianping,Xu, Qing,Sickert, Marcel,Chen, Lianhui,Lautens, Mark
supporting information, p. 3444 - 3449 (2014/07/08)
In contrast to conventional activation of Nu-SiR3 reagents by F ion attributed to the strong affinity of Si to F, S-Si activation can now be achieved using Cl/Br ions of TBAX as catalysts via formation of weaker X-Si bonds and Me3Si-X. This led to a waste-free synthesis of unsymmetrical thioethers via F-free SNAr reactions of activated (hetero)aryl halides and RS-SiMe3, with recovery of the useful Me3Si-X reagent in high yields. This journal is the Partner Organisations 2014.
Green chemical synthesis of 2-benzenesulfonyl-pyridine and related derivatives
Trankle, William G.,Kopach, Michael E.
supporting information, p. 913 - 917 (2012/12/30)
A practical synthesis of 2-benzenesulfonylpyridine, 1, is described which is a key starting material for the manufacture of an investigational new drug candidate at Eli Lilly and Company. An optimized green chemical process was developed which features a novel tandem SNAr/oxidation under mild conditions to produce the target sulfone, 1, in 86% yield and>99% purity. In addition, this novel, environmentally friendly methodology was found to be general for the synthesis of substituted aromatic pyridyl sulfides and sulfones.
Synthesis and Reaction of Methylbenzoquinolizinium Salts
Arai, Sadao,Yamazaki, Masuo,Hida, Mitsuhiko
, p. 1073 - 1078 (2007/10/02)
All isomers of (monomethyl)benzoquinolizinium salts including five new monomethyl derivatives were prepared by photocyclization, sulfur extrusion, or cyclodehydration reaction, and their aldol-type condensation was examined.The 2- and 4-methyl derivati
