Epoxy-based oligomeric probe bearing naphthalene units for selective turn-OFF fluorescent sensing of fluoride anion

A simple epoxy-based oligomer 1 bearing naphthalene unit at the chain-ends is reported to be highly selective ON–OFF type fluorescent probe for fluoride anion. The titled oligomer displayed fluorescence quenching upon addition of F−, resulting in selective detection of fluoride anion over other anions, such as AcO−, Cl−, Br−, I−, HSO4−, NO3− and H2PO4− in CH3CN. Fluorescence experiments suggest the significant influence of the oligomer chain on the sensitivity and selectivity of 1 towards fluoride anion.