Capturing aqueous [18F]-fluoride with an arylboronic ester for PET: Synthesis and aqueous stability of a fluorescent [18F]-labeled aryltrifluoroborate

The aqueous stability of aryltrifluoroborates is of importance to their use in transition metal mediated coupling reactions as well as their potential use in [18F]-labeled aryltrifluoroborate PET imaging agents. Nevertheless, few studies have fully characterized the solvolysis of fluoride from an aryltrifluoroborate in water. Using [19F] NMR, fluorescence and [18F]-labeling techniques, we disclose the composition of an aryltrifluoroborate of exceptional kinetic stability with respect to solvolytic defluoridation. This work not only highlights the potential of using [18F]-labeled aryltrifluoroborates for PET tracers, but provides a chemical platform and a general approach for evaluating the stability of other aryltrifluoroborates.

Graphical abstractThe aqueous stability of aryltrifluoroborates is of importance to their use in transition metal mediated coupling reactions as well as their potential use in [18F]-labeled aryltrifluoroborate PET imaging agents. Nevertheless, few studies have fully characterized the solvolysis of fluoride from an aryltrifluoroborate in water. Using [19F] NMR, fluorescence and [18F]-labeling techniques, we disclose the composition of an aryltrifluoroborate of exceptional kinetic stability with respect to solvolytic defluoridation. This work not only highlights the potential of using [18F]-labeled aryltrifluoroborates for PET tracers, but provides a chemical platform and a general approach for evaluating the stability of other aryltrifluoroborates.Figure optionsDownload full-size imageDownload as PowerPoint slide