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Updated: May 20, 2026
10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Assessing Benzene Dimer Interactions in Solution With a Molecular Balance.
Marvin H J Domanski1, Michael Fuhrmann1, Nils F Hacket1
1Institute of Organic Chemistry, Justus Liebig University, Giessen, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|May 19, 2026
Summary
A molecular balance using cyclooctatetraene (COT) shows the folded 1,6-dibenzyl COT isomer is favored over the unfolded 1,4-isomer. This preference is driven by London dispersion interactions between aromatic groups in solution.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
- Computational Chemistry
Background:
- Benzene dimer interactions are crucial in understanding non-covalent forces in organic systems.
- Cyclooctatetraene (COT) derivatives offer unique conformational flexibility for studying such interactions.
Purpose of the Study:
- To model and quantify benzene dimer interactions in solution using a dibenzyl-substituted COT molecular balance.
- To investigate the conformational equilibrium between 1,4- and 1,6-dibenzyl COT isomers.
Main Methods:
- Utilized a combination of experimental Nuclear Magnetic Resonance (NMR) spectroscopy and computational studies.
- Analyzed the equilibrium between unfolded (1,4-) and folded (1,6-) dibenzyl COT isomers in various organic solvents.
Main Results:
- The folded 1,6-dibenzyl COT isomer was consistently favored over the 1,4-isomer by approximately 0.3 kcal mol⁻¹.
- This energetic preference was observed irrespective of the solvent used in the study.
- Computational analysis identified London dispersion (LD) interactions as the primary stabilizing force in the 1,6-COT isomer.
Conclusions:
- London dispersion forces play a significant role in stabilizing folded aromatic systems in solution.
- The dibenzyl-substituted COT serves as an effective molecular model for probing non-covalent aromatic interactions.
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