Direct C-H Bond Arylation of (Hetero)arenes with Aryl and Heteroarylboronic Acids

Abstract

A novel microwave-promoted protocol mediated by Mn(OAc) 3 was developed for the single-electron-transfer oxidative direct C-H bond arylation of (hetero)arenes with aryl and heteroarylboronic acids. Various electron-deactivated and electron-rich heteroarenes and benzene underwent successfully the direct arylation in this general process. The use of slight excess of heteroarene or benzene in this method was found to be sufficient.

Transition Metal‐Mediated Direct CH Arylation of Heteroarenes Involving Aryl Radicals

“…[90] The single-electron transfer oxidative radical cross-coupling could be carried out with electron-rich as well as electron-poor heterocycles thanks to the microwave activation. Phenylboronic acid and electron-deficient pyridine were chosen as model substrates for the optimization of the reaction conditions ( Scheme 29).…”

5-(p-Tolyl)isoxazol-3-amine-Palladium(II) Complex: Preparation, Structure, and Catalytic Application in the Suzuki-Miyaura Reaction in Water

“…Typically the use of 0.001-0.0001 mol% palladium catalyst gave the biaryl compounds in high yields with TON up to 1000000 and TOF up to 12000000 h -1 . One can expect that complex 7 would be useful in other types of catalytic processes, such as oxidative cross-coupling of two different nucleophiles, 10 oxidative direct C-H bond arylation of (hetero)arenes with arylboronic acids, 11 and cross-coupling reactions of allylic electrophiles 12 or a-bromo carbonyl compounds 13 with organoboron-based nucleophiles.…”

Palladium‐Catalyzed Regioselective C‐2 Arylation of Benzofurans with N′‐Acyl Arylhydrazines

“…In general, these C‐2 arylation reactions are palladium‐catalyzed processes. Other transition‐metal catalysts, such as copper salts, rhodium salts and manganese salts have also proved to be efficient, giving arylated products in moderate yields. It should be noted that some metal‐free reaction systems have also been successfully developed for this transformation.…”