Synthesis of gelation-induced emissive, o-phenylazonaphthol-based organogel and its responsiveness to fluoride anion

Type your Abstract text here An organogelator based on o-phenylazonaphthol (o-AN) was synthesized to achieve gelation-induced emission using the resultant organogel. Although the o-AN-containing organogelator did not fluoresce in solution, its resulting organogel became red fluorescent. The fluorescence originated from the aggregation-induced emissive property of o-AN. The structural planarization, required for gelation was induced by the intramolecular hydrogen bond of the o-AN in the organogelator, leading to an intermolecular π-π interaction. The gelation was also facilitated by the non-covalent interaction of the van der Waals force. The gelation was investigated in terms of a molecular packing model and the organogel fluorescence. The organogel collapsed upon exposure to the fluoride anion, because the hydroxyl group of the o-AN was deprotonated, resulting in a weakened hydrogen bond and, finally, the disappearance of fluorescence. The organogel is potentially promising for applications such as ion sensing and stimuli-responsiveness-related fields.