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Synthesis of sulfamoyl [18F]­fluorides has been a challenging topic owing to the inefficient nucleophilic radiofluorination of sulfamoyl derivatives. Herein, we report an 18F/19F isotopic exchange approach to synthesize various sulfamoyl [18F]­fluorides, otherwise inaccessible via direct synthesis from amines, with high radiochemical yields up to 97% (30 examples). This late-stage labeling protocol offers an efficient route to yield functionalized molecules by diversifying the chemical library possessing sulfamoyl functionalities through nucleophilic 18F incorporation within nitrogen-containing sulfur­(VI) frameworks.

Sulfuryl fluoride gas is a key reagent for SO2F transfer. However, conventional SO2F transfer reactions have limited 18F-radiochemistry translation, due to the inaccessibility of gaseous [18F]­SO2F2. Herein, we report the first SO2F2-free synthesis of aryl [18F]­fluorosulfates from both phenolic and isolated aryl imidazylate precursors with cyclotron-produced 18F–. The radiochemical yields ranged from moderate to good with excellent functional group tolerance. The reliability of our approach was validated by the automated radiosynthesis of 4-acetamidophenyl [18F]­fluorosulfate.

Hypervalent diaryliodonium salts have been used to produce various [18F]­fluoroarenes. The iodonium salt approach as a labeling precursor has been established to equally afford complex 18F-fluorinated molecules. Because of the inherent two aryl ring system connected to a central iodine atom, safeguarding the chemoselectivity during radiofluorination using diaryliodonium salts is important. Herein, we introduce a superior chemoselective radiosynthesis of [18F]­fluoroarenes using an aryl­(2,4,6-trimethoxyphenyl)­iodonium tosylate as a precursor for 18F-incorporation, even on electron-rich aryl rings.