Eco-Friendly Solvents for Palladium-Catalyzed Desulfitative CH Bond Arylation of Heteroarenes.

Hfaiedh, Anoir; Yuan, Kedong; BEN Ammar, Hamed; BEN Hassine, Bechir; Soulé, Jean ‐ François; Doucet, HENri

Herein, we report the Pd-catalyzed regioselective direct arylation of heteroarenes in which benzenesulfonyl chlorides are used as coupling partners through a desulfitative cross-coupling that can be performed in diethyl carbonate (DEC) or cyclopentyl methyl ether (CPME) as green and renewable solvents or even in neat conditions instead of dioxane or dimethylacetamide (DMA). Under these solvent conditions, the reaction proceeds with a wide range of heteroarenes. C2- or C5-arylated products were obtained with furan and pyrrole derivatives. Benzofuran was also arylated regioselectively at the C2-position, whereas the reaction proceeds selectively at the C3- or C4-positions if thiophenes and benzothiophenes are used. Moreover, in some cases, especially with 1-methylindole, solvent-free conditions afforded better regioselectivities and/or yields than the reaction performed in the presence of solvents.

SOLVENTS; PALLADIUM; ARYLATION; HETEROARENES; DIOXANE

ChemSusChem, 2015, Vol 8, Issue 10, p1794

1864-5631

Academic Journal

10.1002/cssc.201403429