Nickel Appends Aqueous Fluoride For Radiotracer Synthesis

The 110-minute half-life of ¹⁸F doesn’t give researchers much time when they want to incorporate the isotope into radiotracers for positron emission tomography. A new oxidative fluorination reaction allows chemists to add aqueous fluoride to arenes and alkenes in one step, thereby circumventing the time-consuming fluoride drying procedures typically used in radiotracer synthesis (J. Am. Chem. Soc., DOI: 10.1021/ja3084797). The reaction, developed by Eunsung Lee and Tobias Ritter of Harvard University, along with Jacob M. Hooker of Massachusetts General Hospital, uses arylnickel catalysts in combination with a hypervalent iodine oxidant and aqueous fluoride (example shown). “The transformation represents the first example of fluorination with a first-row transition-metal organometallic and the first example of a reaction that affords aryl fluoride by ¹⁸F–C bond formation at room temperature within seconds using an aqueous solution of ¹⁸F fluoride,” the researchers note. They point out that because the synthesis is relatively simple, it should be easy for radiotracer makers to adopt.