Asymmetric F-fluorination for applications in positron emission tomography

Positron emission tomography (PET) is becoming more frequently used by medicinal chemists to facilitate the selection of the most promising lead compounds for further evaluation. For PET, this entails the preparation of 11 C- or 18 F-labeled drugs or radioligands. With the importance of chirality and fluorine substitution in drug development, chemists can be faced with the challenge of preparing enantiopure molecules featuring the 18 F-tag on a stereogenic carbon. Asymmetric 18 F-fluorination is an emerging field of research that provides an alternative to resolution or conventional S N 2-based radiochemistry. To date, both transition metal complexes and organomediators have been successfully employed for 18 F-incorporation at a stereogenic carbon. To date, both transition metal complexes and organomediators have been employed for enantiocontrolled 18 F-incorporation as an alternative to conventional resolution of S N 2-based radiochemistry.