Bambusuril Recognition of [Au(CN)[2]]^– in Water


      Carola Rando, Julián Vázquez, Jan Sokolov, Zoran Kokan, Marek Nečas, Vladimír Šindelář*
                                                 ^

  Department of Chemistry and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00
                                       Brno, Czech Republic

                                    e-mail: 503709@mail.muni.cz


Bambusurils are macrocyclic compounds that can strongly bind anions in water. Until now, bambusuril
has been investigated as a receptor of different anions including halides, carboxylates, and other
biologically relevant oxoanions such as phosphate, sulfate, and nitrate. Herein, we decided to
study supramolecular complexes between bambusurils and Au(CN)[2]^– in water. Au(CN)[2]^– has
attracted our attention for its unique photochemical properties and its employment in the gold
mining industry. Among all bambusurils, we selected PEG-BU^1 (Fig. 1) for its good solubility in
water. The formation of the complex between PEG-BU and Au(CN)[2]^– was investigated not only by
means of ^1H NMR and ITC methods but also, through UV-Vis spectroscopy. The high stability of the
complex and the photochemical properties of Au(CN)[2]^– gave rise to a novel and accurate assay.
Furthermore, the exceptional features of this new complex make bambusurils promising candidates
with the application in the gold mining industry.




Fig.1 Schematic representation of bambusuril macrocycle PEG-BU.



This work was supported by the Czech Science Foundation (No. GA20-13922S).


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Binding to a Neutral Bambusuril in Water and Organic Solvents J. Org. Chem. 2018, 83, 4, 1903–1912