Related Experiment Video
Updated: Jul 24, 2025
09:35
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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Overcrowded Triply Fused Carbo[7]helicene
Albert Artigas1, Florian Rigoulet1, Michel Giorgi2
1Aix Marseille Univ, CNRS, Centrale Marseille, ISM2, 13397 Marseille, France.
Journal of the American Chemical Society
|July 10, 2023
Summary
Researchers synthesized a novel triple carbo[7]helicene with unique contorted geometry. This study challenges traditional aromaticity models using magnetic and electronic analyses, offering new insights into complex polycyclic aromatic hydrocarbons.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Helicenes are polycyclic aromatic hydrocarbons with helical chirality.
- Contorted aromatic systems present unique electronic and structural properties.
- Clar's model is a foundational concept for understanding aromaticity in polycyclic systems.
Purpose of the Study:
- To synthesize a novel, highly contorted multihelicene compound.
- To investigate the aromaticity of this unique molecular architecture.
- To challenge and extend the understanding of aromaticity models.
Main Methods:
- Synthesis via [2 + 2 + 2] cycloaddition of 13,14-picyne using a Ni(0) catalyst.
- Comprehensive analysis employing magnetic and electronic criteria.
- Comparison of Ni(0) catalyst performance against conventional Pd(0) catalysts.
Main Results:
- Successful synthesis of a triple carbo[7]helicene featuring a doubly negatively curved structure.
- Ni(0) catalyst demonstrated superior efficiency in the cycloaddition reaction.
- Evaluation of aromaticity provided insights that challenge the applicability of Clar's model.
Conclusions:
- The synthesized multihelicene possesses a unique, highly contorted geometry.
- The study highlights the limitations of Clar's model for complex aromatic systems.
- This work contributes to the understanding of aromaticity in non-planar polycyclic aromatic hydrocarbons.
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