Radiofluorinated 4-fluorobenzonitrile oxide and N-hydroxy-4-fluorobenzimidoyl chloride rapidly react with different alkenes and alkynes under mild conditions. These cycloadditions are suitable for the preparation of low-molecular weight radiopharmaceuticals and, in a strain-promoted variant, can enable easy labelling of sensitive biopolymers.
Zlatopolskiy, B. D., Kandler, R., Kobus, D., Mottaghy, F. M., & Neumaier, B. (2012). Beyond azide-alkyne click reaction: easy access to 18F-labelled compounds via nitrile oxide cycloadditions. Chemical Communications, 48(57), 7134-7136. https://doi.org/10.1039/c2cc31335a