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A Practical General Method for the Preparation of Long Acenes
Andrej Jancarik1,2, Gaspard Levet3, André Gourdon3
1CEMES-CNR, 29 Rue J. Marvig, 31055, Toulouse, France.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 4, 2018
Summary
Researchers developed a new method to synthesize larger acenes, which are important for organic electronics. This Diels-Alder reaction followed by decarbonylation overcomes solubility and reactivity issues, enabling scalable production of these valuable materials.
Area of Science:
- Organic Chemistry
- Materials Science
Background:
- Long acenes, a type of graphene nanoribbon, are crucial for organic electronics, spintronics, and plasmonics.
- Previous synthesis methods were limited by low solubility and high reactivity, hindering large-scale production.
Purpose of the Study:
- To develop a concise and scalable strategy for synthesizing higher acenes.
- To overcome the limitations of solubility and reactivity in acene preparation.
Main Methods:
- Utilized Diels-Alder condensation of arynes with a protected tetraene ketone.
- Employed deprotection via ketal cleavage followed by quantitative cheletropic thermal decarbonylation in the solid state.
Main Results:
- Successfully synthesized heptacene, benzo[a]hexacene, and cis- and trans-dibenzopentacene.
- Demonstrated a scalable method for producing higher acenes at moderate temperatures (155-205°C).
Conclusions:
- The developed strategy provides a valuable new route for synthesizing larger acenes.
- This method facilitates the preparation of acenes with potential for advanced electronic applications.
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