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The development of the oxidative cross-coupling of unreactive C(sp3)–H bonds with (hetero)arene C(sp2)–H bonds is considerably appealing, yet conceptually and practically challenging. Here, we disclose the rhodium-catalyzed oxidative heteroarylation of unactivated C(sp3)–H bonds with heteroarene C(sp2)–H bonds. This method provides a step-economic route to β-heteroarylated 2-ethylpyridine derivatives, which exhibits relatively broad substrate scope, high tolerance level of sensitive functional groups, and high selectivity. The protocol can also be extended to the coupling reaction between 8-methylquinoline derivatives and heteroarenes.

β-Azolyl propanoic acid derivatives are frequently found in biologically active molecules and pharmaceuticals. Here, we report the oxidative heteroarylation of unactivated C(sp3)–H bonds with azole C(sp2)–H bonds via copper or nickel catalysis with the aid of removable bidentate auxiliary, which provides a rapid pathway to β-azolyl propanoic acid derivatives. A variety of azoles such as oxazole, benzoxazole, thiazole, benzothiazoles, benzimidazole, purine, and even [1,2,4]triazolo[1,5-a]pyrimidine could be engaged in this protocol.

Active pyrylium intermediates are in situ generated by a Rh-catalyzed vinylic C–H annulation reaction between exocyclic α,β-enones and alkynes, which undergo a base-promoted rearrangement via 1,5-H shift to form 1H-benzo[f]chromene derivatives.