Cu‐catalyzed Formal Addition of Aliphatic C(sp3)–H Bonds to Alkenes via Phenyl Radical Involved Intermolecular HAT

A copper catalyzed aerobic formal addition of aliphatic C(sp3)–H bonds to alkenes via a phenyl radical mediated intermolecular HAT process is reported herein, in which the phenylhydrazine not only acts as a good HAT reagent precursor but also as an excellent hydrogen atom donor. This reaction affords an alternative method for the direct formal addition of the aliphatic C(sp3)–H bonds to alkenes utilizing air as the radical initiator without additional reductants at the ambient temperature. A variety of alkanes and electron‐deficient alkenes are successfully incorporated, furnishing a series of aliphatic C(sp3)–H formal addition products in 20‐93% yields. The preliminary mechanistic studies uncover that the 2‐tetrahydrofuranyl and phenyl radical are formed in this reaction.