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Article dans une revue
Palladium-catalyzed heteroaryl thioethers synthesis overcoming palladium dithiolate resting states inertness: Practical road to sulfones and N H-sulfoximines
Abstract : 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.
https://hal-univ-bourgogne.archives-ouvertes.fr/hal-01857091
Contributeur : Icmub - Université de Bourgogne <>
Soumis le : mardi 14 août 2018 - 10:56:33
Dernière modification le : vendredi 13 novembre 2020 - 09:08:03
Contributeur : Icmub - Université de Bourgogne <>
Soumis le : mardi 14 août 2018 - 10:56:33
Dernière modification le : vendredi 13 novembre 2020 - 09:08:03