N, N'-Disubstituted methylenediimidazolium bromide salts substituted with two aromatic groups present two different binding sites. In the binary complexes with cyclodextrins (CDs) or cucurbit[7]uril (CB[7]), the macrocycle is always positioned on the external aromatic residues. In the ternary complexes, CB[7] is positioned around the diimidazolium cation, where the external aromatic residue is included in the CD's cavity. The unfavored position of the CB[7] on the cationic site in the ternary complex is the result of its cooperative supramolecular interaction with the cyclodextrin. The obtained ternary complexes possess different interfacial properties, compared to those of the binary complexes. We demonstrate these hypotheses by NMR spectroscopy, ESI-HRMS spectrometry, molecular modeling simulation, and surface tension measurements.

The combination of imidazolium surfactants with alpha-cyclodextrins (CDs, in green) was used as a control element in the thermoregulated aqueous olefin hydroformylation. The self-assembly of the imidazolium surfactants (red) favors the micellization process at high temperatures, whereas at lower temperatures the complexation of the surfactant monomers into the alpha-CDs is favored.

A new family of dialkyl(1,4-phenylene)diimidazolium salts has been synthesized. Salts containing triflate and bis(trifluoromethanesulfonyl)imide anions and different alkyl chains have been prepared. The molecular structures of didodecyl(1,4-phenylene)diimidazolium triflate and bis(trifluoromethylsulfonyl)imide salts were determined by single crystal X-ray diffraction, and the mesomorphic and ionic conducting properties of all these compounds were investigated and are reported here.