Silver-Mediated 18F-Labeling of Aryl-CF3 and Aryl-CHF2 with 18F-Fluoride

We report the synthesis of 18FarylCF3 and 18FarylCHF2 derivatives from arylCF2Br and arylCHFCl precursors applying a silver-mediated halogen exchange with 18Ffluoride. In the absence of Ag(I)OTf, no reaction takes place at room temperature for both classes of substrates; this result demonstrates the beneficial role of silver(I) as a means to induce 18F-incorporation under very mild conditions.