Synthesis of ¹⁸F-labelled biphenyls via Suzuki cross-coupling with 4-[¹⁸F]fluoroiodobenzene

The SUZUKI reaction of organoboron compounds with 4-[¹⁸F]fluoroiodobenzene has been developed as a novel radiolabelling technique in ¹⁸F chemistry. The cross-coupling reaction of p-tolylboronic acid with 4-[¹⁸F]fluoroiodobenzene was used to screen different palladium complexes, bases and solvents. Optimised reaction conditions (Pd₂(dba)₃, Cs₂CO₃, acetonitrile, 60 °C for 5 minutes) were further applied to the synthesis of various ¹⁸F-labelled biphenyls bearing different functional groups. The reaction proceeded in excellent radiochemical yields of up to 94 % within 5 min while showing good compatibility to many functional groups.