[¹⁸F]Fluorination of (mesityl)(aryl)Iodonium Salts

The ability to prepare [¹⁸F]fluoroarenes using high specific activity nucleophilic [¹⁸F]fluoride has long been of interest to the fluorine-18 radiochemistry community, but has not been without its challenges. This chapter discusses the procedures for the synthesis of (Mesityl)(Aryl) iodonium salts. Quality control (QC) procedures must be carried out by trained personnel and each dose must meet all established quality control criteria before release to the clinic. Radio-high-performance liquid chromatography (HPLC) analysis and thin layer chromatography (TLC) analysis are performed as a part of QC procedures. The radiofluorination conditions were applied to a diverse series of (mesityl) (aryl)iodonium tetrafluoroborate salts. The transformation is performed under ambient conditions without the requirement for a drybox or extensive drying of reagents and glassware. (Mesityl)(aryl)iodonium salts derived from aromatic amino acids were prepared and subjected to the radiofluorination protocol to yield protected versions of [¹⁸F]fluoro-L-phenylalanine, the more electronrich 3-[¹⁸F]fluorotyrosine derivative.