A novel heteroacene, 2-(2,3,4,5-tetrafluorophenyl)-1H-imidazo[4,5-b]phenazine as a multi-response sensor for F− detection

A novel heteroacene, 2-(2,3,4,5-tetrafluorophenyl)-1H-imidazo[4,5-b]phenazine has been successfully synthesized. The heteroacene can selectively detect F− over Cl−, Br−, I−, NO3−, HSO4−, ClO4−, and BF4− in organic solvents through colorimetric and fluorescent responses. The interaction between the heteroacene and F− was investigated through UV–Vis, fluorescence, and 1H NMR titration experiments, which suggested that the effects might occur via a combined process including hydrogen bond, deprotonation, and anion–π interactions between the sensor and F−.