A highly selective ratiometric detection of F− based on excited-state intramolecular proton-transfer (imidazole) materials

Abstract

Inspired by the importance of fluoride ions in the field of dental fluorosis and treatment of osteoporosis, we have synthesized a probe 2 (2-(2-tert-butyldiphenylsiloxy)phenyl-4,5-diphenyl-1-p-tolyl-1H-imidazole) for the detection of fluoride ions from simple starting materials. The probe was characterized using standard analytical and spectroscopic techniques including single crystal X-ray crystallography. The probe (2) exhibited a multi-channel rapid response and excellent selectivity and sensitivity towards fluoride ions through selective cleavage of Si–O bonds. Time-dependant density functional theory (TD-DFT) calculations were carried out to vindicate the optical properties of the probe (2) and its starting material (compound 1).