Phosphine-free palladium-catalysed direct C2-arylation of benzothiophenes with aryl bromides
نویسندگان
چکیده
Ligand-free Pd(OAc)2 was found to catalyze very efficiently the direct C2-arylation of benzothiophene derivatives under low catalyst concentration. The reaction can be performed employing as little as 0.5-0.1 mol-% catalyst with electron-deficient and some electron-rich aryl bromides. The presence of a methyl or a formyl substituent at C3 of benzothiophene has a minor influence on the reactivity, and even a bromo substituents at C3 is tolerated. A wide variety of functional groups on the aryl bromide such as nitrile, nitro, acetyl, formyl, ester, chloro, fluoro or trifluoromethyl has been employed. © 2013 Elsevier Science. All rights reserved
منابع مشابه
Phosphine-free palladium-catalyzed direct C2-arylation of benzothiophenes with aryl bromides
Ligand-free Pd(OAc)2 was found to catalyze very efficiently the direct C2-arylation of benzothiophene derivatives under low catalyst concentration. The reaction can be performed employing as little as 0.5-0.1 mol-% catalyst with electron-deficient and some electron-rich aryl bromides. The presence of a methyl or a formyl substituent at C3 of benzothiophene has a minor influence on the reactivit...
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