Late-Stage Fluorination with \(^{18}F\)

Abstract

Positron emission tomography (PET) is a powerful, non-invasive in vivo imaging technique used for diagnostics and drug development. The synthesis of \(^{18}F\)-PET tracers is challenging due to the short half-life of the unnatural isotope that necessitates late-stage fluorination, and the limited reactivity of nucleophilic fluoride, the preferred and widely accessible form of \(^{18}F\). This thesis describes the development of an electrophilic fluorination reagent derived from fluoride. The reagent can be employed in a late-stage fluorination reaction of palladium aryl complexes to give access to small molecule aryl fluorides. The reagent can be made from \([^{18}F]\)fluoride and used to synthesize radiolabeled small molecules for PET imaging experiments. Two small molecules known to interact with the serotonergic system were synthesized, radiolabeled, and imaged in rats and non-human primates and evaluated for use as PET tracers.