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Updated: May 15, 2025
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One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates
Published on: January 15, 2018
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A Pure Rotational Spectroscopic Study of Two Nearly-Equivalent Structures of Hexafluoroacetone Imine, (CF3)C=NH
Daniel A Obenchain1, Beppo Hartwig1, Daniel J Frohman2
1Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany.
Molecules (Basel, Switzerland)
|May 14, 2025
Summary
Rotational spectroscopy revealed two near-equivalent conformers of hexafluoroacetone imine, likely due to large amplitude motion of the CF3 groups. These conformers were analyzed independently, yielding structural properties and nuclear quadrupole coupling constants.
Area of Science:
- Molecular spectroscopy
- Quantum chemistry
- Physical chemistry
Background:
- Hexafluoroacetone imine is an important molecule in chemical research.
- Understanding its conformational properties is key to its applications.
- Previous studies may not have fully elucidated its complex rotational spectra.
Purpose of the Study:
- To investigate the rotational spectra of hexafluoroacetone imine and its isotopologues.
- To determine the structural properties and conformational landscape of hexafluoroacetone imine.
- To compare its properties with isoelectronic molecules.
Main Methods:
- High-resolution microwave spectroscopy (cavity and chirped pulse Fourier transform).
- Analysis of rotational spectra, including isotopologue analysis (13C and 15N).
- Quantum chemical calculations to support experimental findings.
Main Results:
- Observed doubled rotational spectra indicating two torsional substates due to large amplitude CF3 group motion.
- Independent fitting of the two states, suggesting near-equivalent conformers.
- Determination of rotational constants, centrifugal distortion constants, and 14N nuclear electric quadrupole coupling tensor.
Conclusions:
- Hexafluoroacetone imine exists as two distinct, near-equivalent conformers.
- The observed spectral doubling is attributed to internal rotation of the CF3 groups.
- Structural properties were determined and compared with related molecules.
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