Abstract
The complex formed from trimethylamine ((CH3)3N) and trifluoromethanesulfonic acid (triflic acid, CF3SO3H) has been observed by Fourier transform microwave spectroscopy in a supersonic jet. Spectroscopic data, most notably 14N nuclear quadrupole coupling constants, are combined with computational results at several levels of theory to unambiguously demonstrate complete or near-complete proton transfer from the triflic acid to the trimethylamine upon complexation. Thus, the system is best regarded as a trimethylammonium triflate ion pair in the gas phase. The formation of an isolated ion pair in a 1:1 complex of a Brønsted acid and base is unusual and likely arises due to the strong acidity of triflic acid. Simple energetic arguments based on proton affinities and the Coulomb interaction energy can be used to rationalize this result.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 5061-5068 |
| Number of pages | 8 |
| Journal | Journal of Physical Chemistry A |
| Volume | 125 |
| Issue number | 23 |
| DOIs | |
| State | Published - Jun 17 2021 |
Bibliographical note
Funding Information:This work was supported by the National Science Foundation (Grants CHE 1563324 and CHE 1953528) and the Minnesota Supercomputing Institute. N.L. was supported, in part, by a Lester C. and Joan Krogh-Excellence Fellowship at the University of Minnesota.
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PubMed: MeSH publication types
- Journal Article