Modulating the Sensor Response to Halide Using NBD-Based Azamacrocycles

• Published in: Inorganic chemistry Vol. 53; no. 9; pp. 4560 - 4569
• Main Authors: Amatori, Stefano, Ambrosi, Gianluca, Borgogelli, Elisa, Fanelli, Mirco, Formica, Mauro, Fusi, Vieri, Giorgi, Luca, Macedi, Eleonora, Micheloni, Mauro, Paoli, Paola, Rossi, Patrizia, Tassoni, Aurora
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 05.05.2014
• Subjects: Aza Compounds - chemistry; Halogens - chemistry; Ligands; Macrocyclic Compounds - chemistry; Proton Magnetic Resonance Spectroscopy
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/ic5001649

Ligand L (2,6-bis{[7-(7-nitrobenzo[1,2,5]oxadiazole-4-yl)-3,10-dimethyl-1,4,7,10-tetraazacyclododeca-1-yl]methyl}phenol) is a fluorescent sensor that is useful for detecting Cu(II), Zn(II), and Cd(II). Some of the complexes formed are able to sense the presence of halides in solution. L passes through the cellular membrane, becoming fluorescent inside cells. The H –1 L – species is able to form dinuclear complexes with [M2H –1 L]3+ stoichiometry with Cu(II), Zn(II), and Cd(II) ions, experiencing a CHEF effect upon metal coordination in an acetonitrile/water 95:5 (v/v) solution. In all three of the complexes investigated, the metal cations are coordinatively unsaturated and can therefore bind secondary ligands as anionic species. The crystal structure of [Cd2(H –1 L)Cl2](ClO4)·4H2O is discussed. The Zn(II) complex behaves as an OFF–ON sensor for fluoride and chloride anions.