Catalysis of Free C-C Bond Rotation: C-F---H-X H-Bonds Find a Catalytic Role
Muyuan Wang1, Aarush Prasad1, Nathaniel G Garrison1
1Department of Chemistry, Johns Hopkins University, 3400 N. Charles St., Baltimore, Maryland 21218, United States.
Journal of the American Chemical Society
|February 10, 2025
Summary
This study demonstrates the catalysis of hindered carbon-carbon bond rotation using a novel N-H---F-C hydrogen bond. This breakthrough facilitates 360° molecular rotation, advancing organic chemistry dynamics.
Area of Science:
- Organic Chemistry
- Physical Chemistry
- Supramolecular Chemistry
Background:
- Carbon-carbon (C-C) bond rotation is fundamental to molecular structure and dynamics.
- Catalysis of hindered C-C bond rotation remains a significant challenge in organic chemistry.
- Understanding and controlling molecular rotation is crucial for designing novel materials and catalysts.
Purpose of the Study:
- To report a unique model system for the catalysis of 360° C-C bond rotation.
- To document the mechanism involving a transient N-H---F-C hydrogen bond.
- To investigate the role of secondary interactions in facilitating bond rotation.
Main Methods:
- Development of a specialized molecular model system.
- Utilizing a transient N-H---F-C hydrogen bond as a key catalytic element.
- Employing "dual" charge-induced n → π* interactions and ion pairing effects.
Main Results:
- Successful demonstration of catalyzed 360° C-C bond rotation.
- Identification of the N-H---F-C hydrogen bond as a critical linchpin for catalysis.
- Evidence for the significant contribution of secondary interactions to the catalytic process.
Conclusions:
- The developed model system provides clear documentation of C-C bond rotation catalysis.
- Transient hydrogen bonds can effectively catalyze hindered bond rotations.
- Synergistic effects of multiple non-covalent interactions can be harnessed for molecular control.
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