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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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Mechanical Strain-Controlled Aromaticity in Cyclo[n]Carbons
O A Stasyuk1, C Curutchet2,3, A J Stasyuk2,3,4
1Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, C/ Maria Aurèlia Capmany 69, Girona, Catalonia, 17003, Spain.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 25, 2025
Summary
Mechanical strain impacts cyclocarbon aromaticity. Radial contraction enhances electronic delocalization, transforming C18 into a highly aromatic system, offering a strategy for stable cyclocarbon design.
Area of Science:
- Computational chemistry
- Materials science
- Organic chemistry
Background:
- Cyclocarbons exhibit unique electronic and mechanical properties.
- Their high reactivity poses challenges for experimental study and application.
Purpose of the Study:
- To investigate the effect of mechanical strain on the aromaticity of C16 and C18 cyclocarbons.
- To explore strategies for enhancing cyclocarbon stability through mechanical manipulation.
Main Methods:
- Molecular modeling was employed to simulate mechanical strain.
- Aromaticity was assessed using magnetic (NICS, GIMIC) and electronic (π-EDDB, AV1245) indices.
Main Results:
- Uniaxial tension slightly decreased aromaticity in both C16 and C18.
- Radial expansion led to a significant loss of aromaticity.
- Radial contraction enhanced electronic delocalization, particularly in C18.
Conclusions:
- Radial contraction is a viable strategy to increase cyclocarbon aromaticity and stability.
- An 8% radial contraction of C18 resulted in a highly aromatic system with equalized bond lengths.
- This finding provides a pathway for designing stable, strained cyclocarbon architectures.
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