Hypervalent Iodine(III) Carboxylates Enable Direct Radiosynthesis of ¹⁸ F-Labeled Aliphatic Sulfonyl Fluorides

Sulfur(VI) fluoride exchange (SuFEx) chemistry has enabled the widespread use of sulfur-fluoride compounds in diverse fields, particularly in positron emission tomography (PET) imaging. However, efficient methods for incorporating SO₂-¹⁸F into aliphatic frameworks are lacking, limiting access to structurally diverse probes. Here, we report a direct ¹⁸F-labeling strategy that converts aliphatic hypervalent iodine(III) carboxylates or carboxylic acids into alkyl-SO₂-¹⁸F derivatives, expanding the PET imaging toolkit and enabling the development of new radiotracers.