Probing hydrogen bonding in CF₃-substituted Hydroxy-functionalized ionic liquids by FTIR spectroscopy and DFT calculations Full article
| Journal |
Journal of Molecular Liquids
ISSN: 0167-7322 , E-ISSN: 1873-3166 |
||
|---|---|---|---|
| Output data | Year: 2026, Volume: 453, Article number : 129543, Pages count : DOI: 10.1016/j.molliq.2026.129543 | ||
| Authors |
|
||
| Affiliations |
|
Abstract:
Hydroxy-functionalized ionic liquids are a promising class of task-specific ionic liquids in which one or more
hydroxyl groups are incorporated into the cation, resulting in novel physicochemical properties. One of the
interesting phenomena stemming therefrom is the formation of “anti-electrostatic” hydrogen bonds between the
hydroxyl groups of adjacent cations. Herein, a series of new ionic liquids containing cations with 1,1,1-trifluoro2-hydroxypropyl group have been synthesized. These include the 1-(1,1,1-trifluoro-2-hydroxypropyl)-3-methylimidazolium ([HOCH(CF₃)CH₂MIM]+) and 1-(1,1,1-trifluoro-2-hydroxypropyl)-2,3-dimethylimidazolium
([HOCH(CF₃)CH₂DMIM]+) cations in combination with [Br]− , [BF₄]
− , and [NTf₂]
− anions. Formation of
hydrogen bonds between the OH groups and the influence of CF3 substituents on this interaction were studied by
means of ATR-FTIR spectroscopy and single-crystal X-ray diffraction. The OH group of the HOCH(CF₃)CH₂
moiety exhibits a stronger interaction with the anions than in the HOCH₂CH₂ counterpart. The acidic properties
of ILs containing the HOCH(CF₃)CH₂ group are similar to those of 2,2,2-trifluoroethanol. The O–H stretching
vibration bands affected by hydrogen bonding with the OH of the adjacent cations were identified. DFT calculations combined with non-covalent bonding analysis using the independent gradient model based on Hirshfeld
partition (IGMH) witness that hydrogen bonds between the OH groups, as well as between other hydrogen atoms
in the HOCH(CF₃)CH₂ group of the cations play the key role in the cation-anion as well as cation-cation
interactions.
Cite:
Shalygin A.S.
, Bryliakov K.P.
Probing hydrogen bonding in CF₃-substituted Hydroxy-functionalized ionic liquids by FTIR spectroscopy and DFT calculations
Journal of Molecular Liquids. 2026. V.453. 129543 . DOI: 10.1016/j.molliq.2026.129543 Scopus OpenAlex
Probing hydrogen bonding in CF₃-substituted Hydroxy-functionalized ionic liquids by FTIR spectroscopy and DFT calculations
Journal of Molecular Liquids. 2026. V.453. 129543 . DOI: 10.1016/j.molliq.2026.129543 Scopus OpenAlex
Dates:
| Submitted: | Feb 11, 2026 |
| Accepted: | Apr 1, 2026 |
| Published online: | Apr 3, 2026 |
Identifiers:
| ≡ Scopus: | 2-s2.0-105034731486 |
| ≡ OpenAlex: | W7148786453 |