title: Imidazoanthraquinone derivatives for the chromofluorogenic sensing of basic anions and trivalent metal cations.
abstract: Four imidazoanthraquinone derivatives (2a-d) were synthesized and characterized and their coordination behavior against selected anions and cations tested. Acetonitrile solutions of probes showed charge-transfer absorptions in the 407-465 nm range. The four probes emitted in the 533-571 nm interval. The recognition ability of 2a-d was evaluated in the presence of F(-), Cl(-), Br(-), I(-), OCN(-), BzO(-), ClO4(-), AcO(-), HSO4(-), H2PO4(-), and CN(-). Only F(-), AcO(-), and H2PO4(-) induced a new red-shifted absorption band that was attributed to a deprotonation process involving the amine moiety of the imidazole ring. Moreover, upon increasing quantities of F(-), AcO(-), and H2PO4(-), moderate quenching was induced in the emission of 2a-d together with the appearance of a new red-shifted band. The UV-visible and emission behavior of the four probes in the presence of Cu(2+), Co(2+), Mg(2+), Fe(3+), Ba(2+), Fe(2+), Ni(2+), Ca(2+), Zn(2+), Pb(2+), Cd(2+), Cr(3+), Al(3+), K(+), and Li(+) was also assessed. Only addition of Fe(3+), Cr(3+), and Al(3+) caused a new blue-shifted band in 2a-d that was ascribed to a preferential coordination with the acceptor part of the probes. Moreover, an important quenching of the emission was observed which was ascribed to the interaction between these trivalent cations and 2a-d.
authors.affiliation: Centro de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), Unidad Mixta Universidad de Valencia-Universidad Politécnica de Valencia , Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Marín-Hernández
authors.forename: Luis E
authors.initials: LE
authors.lastname: Santos-Figueroa
authors.forename: María E
authors.initials: ME
authors.lastname: Moragues
authors.forename: M Manuela M
authors.initials: MM
authors.lastname: Raposo
authors.forename: Rosa M F
authors.initials: RM
authors.lastname: Batista
authors.forename: Susana P G
authors.initials: SP
authors.lastname: Costa
authors.forename: Teresa
authors.initials: T
authors.lastname: Pardo
authors.forename: Ramón
authors.initials: R
authors.lastname: Martínez-Máñez
authors.forename: Félix
authors.initials: F
authors.lastname: Sancenón
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000838:Anions / Q000737:chemistry*; D000880:Anthraquinones / Q000138:chemical synthesis* / Q000737:chemistry*; D002412:Cations / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*; D015394:Molecular Structure; D013050:Spectrometry, Fluorescence
chemical_list: D000097:Acetonitriles; D000838:Anions; D000880:Anthraquinones; D002412:Cations; D008670:Metals; C032159:acetonitrile