Palladium-mediated cross-coupling reactions with [¹¹C]methyl iodide and 4-[¹⁸F]fluorohalobenzenes for the synthesis of positron emission tomography (PET) radiotracers

Radiochemistry with the short-lived positron emitters ¹¹C (¹¹C, t_1/2 =20.38 min) and ¹⁸F (¹⁸F, t_1/2 = 109.6 min) represents special challenges in terms of synthesis time and applicable labelling techniques. The implementation of modern organic chemistry methods into ¹¹C and ¹⁸F radiochemistry has steadily expanded the number of ¹¹C- and ¹⁸F- labelled PET radiotracers. The review wants to address the progress in the development of palladium-mediated carbon-carbon and carbon-heteroatom bond formations based on the readily available labelling precursors [¹¹C]methyl iodide and 4-[¹⁸F]fluorohalobenzenes (4-[¹⁸F]bromofluorobenzene and 4-[¹⁸F]fluoroiodobenzene).