The Construction of C–N, C–O, and C(sp2)–C(sp3) Bonds from Fluorine-Substituted 2-Aryl Benzazoles for Direct Synthesis of N-, O-, C-Functionalized 2-Aryl Benzazole Derivatives

Herein, a general and practical route to 2-(2-aminophenyl)- and 2-(2-alkoxyphenyl)-substituted benzazoles by nucleophilic aromatic substitution (SNAr) is described. Upon treatment with Cs2CO3, the formation of C–N, C–O bonds occur between fluorine-substituted 2-aryl benzazoles and a diverse range of nitrogen, oxygen nucleophiles to provide the targets in good to excellent yields. Commercially available nucleophiles and high atom economy are notable features of the protocol. Meanwhile, the construction of C(sp2)–C(sp3) bond was also furnished in the presence of palladium catalyst.