[1] It involves the reaction of an independently generated carbon-centered radical with an atomic fluorine source and yields an organofluorine compound.
Their high reactivity, and the difficult handling of F2 and the hypofluorites, limited the development of radical fluorination compared to electrophilic and nucleophilic methods.
The reaction of F2 with organic compounds is, however, highly exothermic and can lead to non-selective fluorinations and C–C cleavage, as well as explosions.
[12] In this Hunsdiecker-type reaction, xenon difluoride is used to generate the radical intermediate, as well as the fluorine transfer source.
[citation needed] The thermolysis of t-butyl peresters has been used to generate alkyl radicals in presence of NFSI and Selectfluor.
[19][20] More specifically, phenoxyacetic acid derivatives have been shown to undergo fluorodecarboxylation when directly exposed to ultraviolet irradiation[21] or via the use of a photosensitizer.
Hydrides[23] and nitrogen-,[24] carbon-,[25] and phosphorus-centered[26] radicals have been employed, yielding a wide range of fluorinated difunctionalized compounds.
[37] One potential application of radical fluorination is for efficiently accessing novel moieties to serve as building blocks in medicinal chemistry.