title: Sulfonamide-imines as selective fluorescent chemosensors for the fluoride anion.
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.
authors.affiliation: Departamento de Química Inorgánica, Facultad de Química, Universidad de Santiago de Compostela, 15782, Santiago de Compostela, Spain. miguel.vazquez.lopez@usc.es
authors.forename: Miguel Vázquez
authors.initials: MV
authors.lastname: López
authors.forename: Manuel R
authors.initials: MR
authors.lastname: Bermejo
authors.forename: M Eugenio
authors.initials: ME
authors.lastname: Vázquez
authors.forename: Angelo
authors.initials: A
authors.lastname: Taglietti
authors.forename: Guillermo
authors.initials: G
authors.lastname: Zaragoza
authors.forename: Rosa
authors.initials: R
authors.lastname: Pedrido
authors.forename: Miguel
authors.initials: M
authors.lastname: Martínez-Calvo
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D018360:Crystallography, X-Ray; D005456:Fluorescent Dyes / Q000737:chemistry*; D005459:Fluorides / Q000032:analysis* / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D013379:Substrate Specificity; D013449:Sulfonamides / Q000737:chemistry*
chemical_list: D000097:Acetonitriles; D005456:Fluorescent Dyes; D007097:Imines; D013449:Sulfonamides; D005459:Fluorides; C032159:acetonitrile