Salicylaldehyde based colorimetric and “turn on” fluorescent sensors for fluoride anion sensing employing hydrogen bonding

Two salicylaldehyde based colorimetric and fluorescent chemosensors 1 and 2 were developed. Both receptors 1 and 2 showed unique selectivity for the fluoride anions over other anions in DMSO solution. [TBA] OH and 1H NMR titration experiments revealed that the F−-induced colorimetric and “turn on” fluorescence response were driven by hydrogen bonding interaction between the OH protons and F−.