Expedient Access to 18F‐Fluoroheteroarenes via Deaminative Radiofluorination of Aniline‐Derived Pyridinium Salts

Herein, we disclose that pyridinium salts derived from abundant (hetero)anilines represent a novel precursor class for nucleophilic aromatic substitution reactions with [ 18 F]fluoride. The value of this new 18 F‐fluorodeamination is demonstrated with the synthesis of over 30 structurally diverse and complex heteroaryl 18 F‐fluorides, several derived from scaffolds that were yet to be labelled with fluorine‐18. The protocol tolerates heteroarenes and functionalities commonly found in drug discovery libraries, and is amenable to scale‐up and automation on a commercial radiosynthesiser.