1. Department of Chemistry, Masaryk University, Kotlarska 2, 61137 Brno (Czech Republic), Fax: (+420)?549‐49‐2443;2. National Centre for Biomolecular Research, Masaryk University, Kamenice 5A4, 62500 Brno (Czech Republic)
Abstract:
In this study, we have investigated the supramolecular interaction between series of 1‐alkyl‐3‐methylimidazolium guests with variable alkyl substituent lengths and cucurbit6]uril (CB6) in the solution and the solid state. Correct interpretation of 1H NMR spectra was a key issue for determining the binding modes of the complexes in solution. Unusual chemical shifts of some protons in the 1H NMR spectra were explained by the polarization of the imidazolium aromatic ring upon the complexation with the host. The formation of 1:1 complex between 1‐ethyl‐3‐methylimidazolium and CB6 is in disagreement with previously reported findings describing an inclusion of two guest molecules in the CB6 cavity.