Anthracene-Fe3+ ensemble based turn-on fluorescent probes for selective detection of fluoride

• Two new and simple chemosensors were synthesized.
• They show highly selective recognition for Fe3+.
• Ensemble 3a-Fe3+ and 3b-Fe3+ complexes show selective detection of F−.
• Both of the Fe3+ and F− recognition processes are reversible.

Two new and simple chemosensors, 1-(anthracen-9-ylmethyl)urea (3a) and 1-(anthracen-9-ylmethyl)thiourea (3b) bearing anthracene moiety, were synthesized from anthracen-9-ylmethanamine. Their UV–Vis absorption, fluorescence emission and potential application for the detection of ions were investigated. Of note is that their fluorescence emission excited with 370 nm could be quenched upon addition of Fe3+, whereby the highly selective recognition for Fe3+ was noticed. Furthermore, ensembles based on 3a-Fe3+ and 3b-Fe3+ complexes having the specific binding affinity for F− show rapid and selective detection of F− over other anions with a fluorescence turn-on mode.

Chemosensors 1-(anthracen-9-ylmethyl)urea (3a) and 1-(anthracen-9-ylmethyl)thiourea (3b) bearing anthracene moiety show highly selective recognition for Fe3+. Furthermore, ensemble 3a-Fe3+ and 3b-Fe3+ complexes show high and selective affinity for F− which restore the fluorescence emission of the system.Figure optionsDownload as PowerPoint slide