File(s) under permanent embargo
Protic ionic liquids based on the dimeric and oligomeric anions: [(AcO)xHx−1]−
journal contribution
posted on 2008-01-01, 00:00 authored by K Johansson, E Izgorodina, Maria ForsythMaria Forsyth, D MacFarlane, K SeddonWe describe a fluidity and conductivity study as a function of composition in N-methylpyrrolidine–acetic acid mixtures. The simple 1:1 acid–base mixture appears to form an ionic liquid, but its degree of ionicity is quite low and such liquids are better thought of as poorly dissociated mixtures of acid and base. The composition consisting of 3 moles acetic acid and 1 mole N-methylpyrrolidine is shown to form the highest ionicity mixture in this binary due to the presence of oligomeric anionic species [(AcO)xHx−1]− stabilised by hydrogen bonds. These oligomeric species, being weaker bases than the acetate anion, shift the proton transfer equilibrium towards formation of ionic species, thus generating a higher degree of ionicity than is present at the 1:1 composition. A Walden plot analysis, thermogravimetric behaviour and proton NMR data, as well as ab initio calculations of the oligomeric species, all support this conclusion.
History
Journal
Physical chemistry chemical physicsVolume
10Issue
20Pagination
2972 - 2978Publisher
Royal Society of ChemistryLocation
Cambridge, EnglandPublisher DOI
ISSN
1463-9076eISSN
1463-9084Language
engPublication classification
C1.1 Refereed article in a scholarly journalCopyright notice
2008, Owner SocietiesUsage metrics
Categories
No categories selectedKeywords
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC