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Journal articles
Regiocontroled Pd-catalysed C5-arylation of 3-substituted thiophene derivatives using a bromo-substituent as blocking group
Abstract : The use of a bromo-substituent as blocking group at the C2-position of 3-substituted thiophenes allows the regioselective introduction of aryl substituents at C5-position via Pd-catalysed direct arylation. With 1 mol % of a phosphine-free Pd catalyst, KOAc as the base and DMA as the solvent and various electron-deficient aryl bromides as aryl sources, C5-(hetero) arylated thiophenes were synthesized in moderate to high yields, without cleavage of the thienyl C-Br bond. Moreover, sequential direct thienyl C5-arylation followed by Pd-catalysed direct arylation or Suzuki coupling at the C2-position allows to prepare 2,5-di(hetero) arylated thiophenes bearing two different (hetero) aryl units in only two steps. This method provides a "green" access to arylated thiophene derivatives as it reduces the number of steps to prepare these compounds and also the formation of wastes.
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01395475
Contributor : Laurent Jonchère <>
Submitted on : Thursday, November 10, 2016 - 5:10:18 PM
Last modification on : Wednesday, October 21, 2020 - 3:08:18 AM
Contributor : Laurent Jonchère <>
Submitted on : Thursday, November 10, 2016 - 5:10:18 PM
Last modification on : Wednesday, October 21, 2020 - 3:08:18 AM
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