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Reduction Inverts the Thermodynamics of the Stone-Wales Rearrangement
Daniel Čavlović1,2, Jacklin H Smith2, Scott R Docherty2
1Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057Zurich, Switzerland.
Journal of the American Chemical Society
|July 30, 2026
Summary
Alkali-metal doping of polycyclic aromatic hydrocarbons enables efficient inverse Stone-Wales rearrangement at low temperatures. This reduction strategy unlocks new chemical pathways for functionalizing carbon nanomaterials like graphene.
Area of Science:
- Organic Chemistry
- Materials Science
- Physical Chemistry
Background:
- Polycyclic aromatic hydrocarbons (PAHs) are fundamental carbon structures.
- Understanding their rearrangements is key to functionalizing carbon nanomaterials.
- Alkali-metal doping is a potential strategy to modify PAH properties.
Purpose of the Study:
- To investigate the effect of alkali-metal doping on PAH potential energy surfaces.
- To explore low-temperature rearrangements in doped PAHs.
- To characterize reaction intermediates and pathways.
Main Methods:
- Density functional theory (DFT) calculations.
- Single-crystal X-ray diffraction.
- UV-vis spectroscopy and magnetometry.
Main Results:
- Potassium, rubidium, and cesium doping facilitate inverse Stone-Wales rearrangement at 250 °C.
- Lithium and sodium doping promote cyclodehydrogenation.
- Key anionic intermediates were isolated and characterized.
Conclusions:
- Alkali-metal reduction can unlock inaccessible rearrangements in PAHs.
- This provides a new route for functionalizing graphene, carbon nanotubes, and fullerenes.
- The findings inform the design of novel carbon-based materials.
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