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From transient to induced permanent chirality in 2-propanol upon dimerization: a rotational study
Mark S Snow1, Brian J Howard, Luca Evangelisti
1Department of Chemistry, University of Oxford, Oxford, United Kingdom.
The Journal of Physical Chemistry. A
|December 15, 2010
Summary
This study identified five hydrogen-bonded conformers of 2-propanol dimers using microwave spectroscopy. The research revealed that these dimers are chiral systems and quantified structural changes upon isotopic substitution.
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Chemical Physics
Background:
- Hydrogen bonding in alcohol dimers is crucial for understanding molecular interactions.
- Conformational analysis provides insights into molecular structure and properties.
- Chirality in molecular systems has significant implications in chemistry and biology.
Purpose of the Study:
- To characterize the hydrogen-bonded conformers of 2-propanol dimers.
- To investigate the conformational preferences and chirality of 2-propanol dimers.
- To study the structural effects of isotopic substitution on the dimer.
Main Methods:
- Fourier transform microwave spectroscopy was employed to study the 2-propanol dimer.
- Analysis of spectral data allowed for the identification and characterization of different conformers.
- Isotopic substitution (OH → OD) was used to probe structural changes.
Main Results:
- Five distinct hydrogen-bonded conformers of the 2-propanol dimer were identified.
- The proton donor moiety in all observed species adopts a gauche conformation.
- All observed dimers were characterized as classical chiral systems.
- The Ubbelohde effect was observed, leading to a quantitative definition of a 5 mÅ reduction in the O---O distance upon isotopic substitution.
Conclusions:
- The study successfully characterized multiple hydrogen-bonded conformers of 2-propanol dimers.
- The research confirms the chiral nature of these dimers and provides detailed structural information.
- The observed Ubbelohde effect offers quantitative data on the impact of isotopic substitution on hydrogen bond geometry.
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