Reactivity of Para‐Substituted Fluorobenzenes in Palladium‐catalyzed Intermolecular Direct Arylations

Abstract

AbstractThe influence of both electron‐withdrawing and electron‐donating substituents such as amino, bromo, chloro, ketone, methyl, methoxy, and nitro at C‐4 on fluorobenzene derivatives, for palladium‐catalyzed direct arylation at α‐position to the fluorine atom has been explored. With moderate electron‐withdrawing substituents, the reaction proceeds nicely using phosphine‐free PdCl2 catalyst, at a very low loading, and potassium pivalate/dimethylacetamide (PivOK/DMA) as catalytic system. In all cases, a regioselective arylation at the α position to the fluorine atom was observed. Moreover, a wide variety of substituents on the aryl bromide coupling partner, such as formyl, nitro, nitrile, chloro, and methyl, and also heteroaryl bromides was tolerated.