Person:

Ritter, Tobias

We report a regiospecific silver-mediated fluorination of aryl stannanes. The presented reaction can afford complex fluoroarenes from readily available phenols in three steps. The operational simplicity and the broad substrate scope of the fluorination should render this reaction a useful tool for the synthesis of milligram to gram quantities of functionalized aryl fluorides. Silver-mediated oxidative transformations of aryl nucleophiles that proceed via bimetallic redox processes are a new avenue to develop carbon−heteroatom bond formations.

The unnatural isotope fluorine-18 ((^{18}F)) is used as a positron emitter in molecular imaging. Currently, many potentially useful (^{18}F)-labeled probe molecules are inaccessible for imaging because no fluorination chemistry is available to make them. The 110-minute half-life of (^{18}F) requires rapid syntheses for which ([^{18}F])fluoride is the preferred source of fluorine because of its practical access and suitable isotope enrichment. However, conventional ([^{18}F])fluoride chemistry has been limited to nucleophilic fluorination reactions. We report the development of a palladium-based electrophilic fluorination reagent derived from fluoride and its application to the synthesis of aromatic (^{18}F)-labeled molecules via late-stage fluorination. Late-stage fluorination enables the synthesis of conventionally unavailable positron emission tomography (PET) tracers for anticipated applications in pharmaceutical development as well as preclinical and clinical PET imaging.