Azadihomocorannulene as a Heptagon-Embedded Diradicaloid
Yosuke Hamamoto1, Weifan Wang1, Yongxin Li1
1School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
Angewandte Chemie (International Ed. in English)
|December 6, 2024
Summary
Researchers synthesized novel azapentabenzodihomocorannulene molecules. These compounds exhibit unique electronic properties, adopting a singlet diradical ground state with potential as functional materials.
Area of Science:
- Organic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Polycyclic aromatic diradical(oid)s are crucial for functional materials due to their electronic and magnetic properties.
- Research on diradical(oid)s with seven-membered rings is less explored compared to those with five-membered rings.
Purpose of the Study:
- To synthesize novel azapentabenzodihomocorannulene dication and diradical molecules.
- To investigate the electronic and magnetic properties of these novel compounds.
Main Methods:
- Mechanochemical C(sp2)-H/C(sp3)-H coupling reaction utilizing sodium.
- Electron spin resonance (ESR) spectroscopy.
- Experimental and theoretical investigations of electronic and optical properties.
Main Results:
- Successful synthesis of azapentabenzodihomocorannulene dication and diradical molecules.
- Neutral azapentabenzodihomocorannulene exhibits a singlet diradical (diradicaloid) ground state.
- A small singlet-triplet energy gap of 2.1 kcal/mol was determined for the diradical.
Conclusions:
- The study presents a novel synthetic route to seven-membered ring-containing polycyclic aromatic diradical(oid)s.
- The synthesized molecules possess unique electronic and optical properties, elucidating their aromatic character.
- These findings contribute to the development of new functional materials with tailored magnetic and electronic characteristics.
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