Uso de interacciones no convencionales para el reconocimiento de aniones

Resum

This doctoral Thesis addresses the study of new anion receptors using nonconventional interactions. Imidazole and imidazolium rings were used as basic anion binding site units. In the first chapter, the synthesis and study of different cyclic and acyclic anion receptors have been carried out. Benzoimidazolium, imidazolium or 2,4,5-trimethylimidazolium rings were used as anion recognition units. From the results obtained, we highlights the ability of 2,4,5-trimethylimidazolium based receptors for anion recognition. In the second and third chapter, a comparative study of two- and three-armed anion receptors has been realized. Anion receptors show identical structure using imidazolium or bromoimidazolium rings as anion recognition binding sites through hydrogen- or halogen-bonding respectively. The halogen bonding based receptors are more selective than the hydrogen bonding based analogs. In adittion, the three-armed receptors are able to generate supramolecular polymers in the presence of anions. In the last chapter, a comparative study of two ion-pairs four-armed receptors has been described, using imidazole or bromoimidazole rings as cation and anion recognition units simultaneously. The halogen-bonding based receptor showed the best selectivity for ion-pair recognition. The molecules synthesized, have been characterized by mass spectrometry, melting point and 1H NMR and 13C NMR spectroscopy. The study of the properties of the receptors as anion recognition sensors has been realized by Fluorescence, UV-Vis and NMR spectroscopy. The supramolecular polymers have also been characterized by Dynamic Light Scattering and DOSY-NMR.