459432-76-9Relevant academic research and scientific papers
Biimidazole diamide anion binding agents
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Page 5, (2008/06/13)
Biimidazole diamide compounds that are useful for binding anions such as sulfate are described, along with the use thereof for purposes such as extracting anions from a waste stream and/or detecting anions.
Anion binding by fluorescent biimidazole diamides
Causey, Corey P.,Allen, William E.
, p. 5963 - 5968 (2007/10/03)
Six 2,2′-biimidazoles with various amide groups at the 4- and 4′-positions were prepared from 5-propyl-1H-imidazole-4-carboxylic acid ethyl ester. In the final step of the synthesis, biimidazole C2-C2′ bond formation was accomplished in 33-45% yield by palladium(0)-catalyzed homocoupling of the corresponding 2-iodoimidazoles. Four of the biimidazoles were studied by X-ray diffraction. In the solid state, all display coplanar imidazole rings, an anti relationship of amide groups, and intramolecular (NHamideNimid) and intermolecular (NHimidOamide) hydrogen bonding. In CH2Cl2, the emission intensity of the biimidazoles is quenched by the presence of dihydrogenphosphate and chloride anions, but no shifts in λemiss are observed. Binding constants for 1:1 biimidazoleanion complexation (Kassoc) are on the order of 104 M-1 for H2PO4- and Cl-. One of the receptors (bearing 3,5-difluorobenzylamides) is selective for chloride. The participation of the amide NH atoms in anion binding was established by 1H NMR.
