Electrochemical fluorodecarboxylation for the labelling of gem-difluoro(cyclo)alkanes/amines

Positron emission tomography (PET) is a powerful molecular imaging modality for diagnosis, monitoring disease progression, studying biological processes in vivo, and investigating the efficacy of drugs. Among the radioisotopes employed for the preparation of PET probes, fluorine-18 is a widely used and clinically relevant radionuclide in part due to its favourable decay properties, and the numerous clinical applications. While radiochemists have in recent years focused their efforts on methods enabling 18F-labelled fluorination and trifluoromethylation of (hetero)arenes, 18F-radiolabelled gem-difluorinated reactions have been much less studied despite the importance of the gem-difluoromethylene group (CF2) in radioligand design for drug discovery programmes. Herein, we propose a solution merging electrochemistry and 18F radiochemistry with the development of a novel electrochemical fluorodecarboxylation process affording 18F-labelled gem-difluoro(cyclo)alkanes and (cyclo)amines including structurally complex pharmaceutical drugs.