Mild and Versatile Nitrate-Promoted C-H Bond Fluorination

摘要

A novel and facile C~H bond fluorination proceeds under remarkably mild conditions (close to room temperature in most cases). Both aromatic and olefinic C(sp~2)—H bonds with a wide range of electronic properties are selectively fluorinated in the presence of a catalytic amount of simple, cheap, and nontoxic nitrate as the promoter. A Pd~(II)/Pd~(IV) catalytic cycle that is initiated by an in situ generated cationic [Pd(NO3)]~+ species was proposed based on preliminary mechanistic studies.