Receptor conformational change induces fluoride binding despite competitive water binding

Fluoride binding by artificial receptors in water remains a challenging task due to the high hydration enthalpy of this anion. A novel cationic boron-based tripodal receptor featuring three flexible ammonium-containing arms has been prepared. NMR spectroscopy studies show that the receptor is capable of binding selectively the fluoride anion with high affinity in acidic water.