2-Thiohydantoin containing OH and NH recognition subunits: a fluoride ion selective colorimetric sensor

A novel anion receptor based on 2-thiohydantoin, containing different hydrogen bonding donors such as OH and NH groups, was synthesized. This receptor showed a colorimetric response to fluoride ions. H-1 NMR titration confirmed the deprontonation of the phenol OH group and hydrogen bonding interaction between NH group and F-