Compound (19) with a triarylborane structure cannot exchange the hydroxyl group for a fluoride anion but can interact by attaching one fluoride anion. Using the DPV technique, we observed the occurrence of a current peak at a potential of 0.2 V, which should correspond to the transfer of the fluoride ion through the interface. The height of the current peak depended on the concentration of fluoride ions in the aqueous phase, as was the case with (15).