Selective and colorimetric fluoride anion chemosensor based on s-tetrazines

Abstract

s-Tetrazine and their derivatives are found to be a class of selective and colorimetric chemosensors for fluoride anions. The supramolecular interaction (anion–π and charge/electron transfer) between fluoride ion and π-electron deficient tetrazines receptor could facilitate the F⁻–tetrazines electron transfer (ET) event that generates tetrazine˙⁻ radical anion. Accordingly, the color of its solution changed from red to green. Furthermore, the recognition of F⁻ in DMSO is tolerant to water (DMSO–H₂O = 9 : 1, v/v) and shows excellent selectivity towards other anions, especially H₂PO₄⁻ and OAc⁻.