6533b835fe1ef96bd129f57a

RESEARCH PRODUCT

Solution and thermal behaviour of novel dicationic imidazolium ionic liquids

Renato NotoKenneth R. SeddonGiuseppe LazzaraFrancesca D'annaCarla RizzoH. Q. Nimal Gunaratne

subject

ProtonOrganic ChemistryInorganic chemistryCationic polymerizationSettore CHIM/06 - Chimica OrganicaBiochemistryionic liquids NMR TGA DSCIonchemistry.chemical_compoundCrystallographychemistryIonic liquidImidazoleThermal stabilityPhysical and Theoretical ChemistrySpectroscopyConformational isomerism

description

A new class of functionalised dicationic ionic liquids, containing a central cationic unit capped by a basic functionality (imidazole), has been synthesised. These salts have been characterised in isotropic solution using proton and 2D-NMR spectroscopy, and their thermal stability has been studied by DSC and TGA. All these novel salts contain the 1-(1-imidazolylmethyl)-3,5-di{1-(3'-octylimidazolylmethyl)}-benzene cation as a defining structural motif. Salts of both singly and doubly charged anions were prepared and, in particular, the selected monoanions (Br(-), [BF4](-), or [NTf2](-)) differ in size, shape and hydrogen-bonding ability, whereas the dianions differ in the nature of the spacer, such as 1,4-benzenedicarboxylate, 2,6-naphthalenedicarboxylate, 1,5- and 2,6-naphthalenedisulfonate, 1,4-butanedicarboxylate, and 1,6-hexanedicarboxylate. These ionic liquids exhibit the presence of different conformers in solution, whose distribution is affected by the nature of the anion. The nature of the anion also affects their thermal stability.

10.1039/c3ob40807hhttp://hdl.handle.net/10447/83003