title: Palladium-catalyzed 2,5-diheteroarylation of 2,5-dibromothiophene derivatives.
abstract: Conditions allowing the one pot 2,5-diheteroarylation of 2,5-dibromothiophene derivatives in the presence of palladium catalysts are reported. Using KOAc as the base, DMA as the solvent and only 0.5-2 mol % palladium catalysts, the target 2,5-diheteroarylated thiophenes were obtained in moderate to good yields and with a wide variety of heteroarenes such as thiazoles, thiophenes, furans, pyrroles, pyrazoles or isoxazoles. Moreover, sequential heteroarylation reactions allow the access to 2,5-diheteroarylated thiophenes bearing two different heteroaryl units.
authors.affiliation: Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes, "Organométalliques: Matériaux et Catalyse", Campus de Beaulieu, 35042 Rennes, France, Tel.: 00-33-2-23-23-63-84, Fax 00-33-2-23-23-69-39 ; Département de chimie, Tizi Ouzou University, BP 17 RP 15000 Tizi-Ouzou, Algeria.
authors.forename: Fatma
authors.initials: F
authors.lastname: Belkessam
authors.affiliation: Département de chimie, Tizi Ouzou University, BP 17 RP 15000 Tizi-Ouzou, Algeria.
authors.forename: Aidene
authors.initials: A
authors.lastname: Mohand
authors.affiliation: Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes, "Organométalliques: Matériaux et Catalyse", Campus de Beaulieu, 35042 Rennes, France, Tel.: 00-33-2-23-23-63-84, Fax 00-33-2-23-23-69-39.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Soulé
authors.affiliation: Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes, "Organométalliques: Matériaux et Catalyse", Campus de Beaulieu, 35042 Rennes, France, Tel.: 00-33-2-23-23-63-84, Fax 00-33-2-23-23-69-39 ; Département de chimie, Tizi Ouzou University, BP 17 RP 15000 Tizi-Ouzou, Algeria.
authors.forename: Abdelhamid
authors.initials: A
authors.lastname: Elias
authors.affiliation: Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes, "Organométalliques: Matériaux et Catalyse", Campus de Beaulieu, 35042 Rennes, France, Tel.: 00-33-2-23-23-63-84, Fax 00-33-2-23-23-69-39.
authors.forename: Henri
authors.initials: H
authors.lastname: Doucet
keywords: C–H bond activation; aryl halides; catalysis; direct arylation; heteroarenes; palladium