Palladium-catalyzed 2,5-diheteroarylation of 2,5-dibromothiophene derivatives
نویسندگان
چکیده
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.
منابع مشابه
Synthesis of functionalized thiophenes and oligothiophenes by selective and iterative cross-coupling reactions using indium organometallics.
The synthesis of unsymmetrical 2,5-disubstituted thiophenes by selective and sequential palladium-catalyzed cross-coupling reactions of indium organometallics with 2,5-dibromothiophene is reported. Following an iterative coupling sequence, α-oligothiophenes were synthesized in good yields and with high atom economy.
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