Related Experiment Video
Updated: Jun 17, 2026

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Sulfonamide-imines as selective fluorescent chemosensors for the fluoride anion
Miguel Vázquez López1, Manuel R Bermejo, M Eugenio Vázquez
1Departamento de Química Inorgánica, Facultad de Química, Universidad de Santiago de Compostela, 15782, Santiago de Compostela, Spain. miguel.vazquez.lopez@usc.es
Abstract:
Two new sulfonamide-type fluorescent chemosensors in organic media are reported. The two receptors, [N,N'-bis(2-tosylaminobenzylidene)-1,2-diaminoethane and N,N'-bis(2-tosylaminobenzylidene)-1,3-diamino-2-propanol], display marked changes in the fluorescence emission intensities as a result of deprotonation by basic anions, and show high selectivity for fluoride over other inorganic anions, such as acetate or dihydrogenphosphate. These results suggest that the presence of the imine group as an intramolecular H-bond acceptor enhances the selectivity of these sensors compared to previous examples in the literature. The deprotonation mechanism has been demonstrated by spectrophotometric and spectrofluorimetric titrations as well as by NMR spectroscopy. The X-ray structures of both receptors are also discussed.
Related Concept Videos
Amines to Sulfonamides: The Hinsberg Test
Generally, a primary amine reacts with the Hinsberg reagent to produce an N-substituted benzenesulfonamide. The electron-withdrawing sulfonyl...
Photoluminescence: Applications
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Immunofluorescence Microscopy
The...
Aryldiazonium Salts to Azo Dyes: Diazo Coupling

