Click for PET: rapid preparation of [18F]fluoropeptides using CuI catalyzed 1,3-dipolar cycloaddition

CuI catalyzed 1,3-dipolar cycloaddition ‘click chemistry’ was used to prepare 18F-radiolabeled peptides. Three ω-[18F]fluoroalkynes were prepared in yields ranging from 36% to 81%. Conjugation of ω-[18F]fluoroalkynes to various peptides decorated with 3-azidopropionic acid via CuI mediated 1,3-dipolar cycloaddition yielded the desired 18F-labeled products in 10 min with yields of 54–99% and excellent radiochemical purity (81–99%). The total synthesis time was 30 min from the end of bombardment.