Synthesis and characterization of 2,6-difluoro-4-carboxyphenylboronic acid and a biotin derivative thereof as captors of anionic aqueous [18F]-fluoride for the preparation of [18F/19F]-labeled aryltrifluoroborates with high kinetic stability

Arylboronic esters are readily converted to aryltrifluoroborates in the presence of aqueous fluoride. As such these represent attractive synthetic precursors that afford one-step labeling with [18F]-fluoride for the generation of PET reagents. Herein we present the synthesis of a heretofore undisclosed arylboronic ester that is converted to its corresponding trifluoroborate. Essential for contemplating its use in PET imaging is the demonstration of kinetic resistance to solvolytic defluoridation.