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Electrochromic Polycationic Organoboronium Macrocycles with Multiple Redox States
Daisuke Shimoyama1, Nurcan Baser-Kirazli1, Roger A Lalancette1
1Department of Chemistry, Rutgers University-Newark, 73 Warren Street, Newark, NJ, 07102, USA.
Angewandte Chemie (International Ed. in English)
|June 10, 2021
Summary
Researchers developed novel polycationic macrocycles featuring organoboronium units. These advanced boron-based macrocycles exhibit remarkable multi-step redox processes and switchable electrochromic properties.
Area of Science:
- Supramolecular Chemistry
- Organometallic Chemistry
- Materials Science
Background:
- Polycationic macrocycles are known for molecular switching capabilities due to redox properties.
- Existing macrocycles are limited in boron-based systems, particularly cationic boron structures.
Purpose of the Study:
- To develop novel polycationic macrocycles incorporating organoboronium moieties.
- To explore the electrochemical and electrochromic properties of these new boron-based macrocycles.
Main Methods:
- Synthesis of conjugated organoboron macrocyclic frameworks with bipyridylboronium units.
- Electrochemical studies (cyclic voltammetry) to analyze redox behavior.
- Spectroelectrochemical studies and Density Functional Theory (DFT) calculations to understand electronic transitions and color changes.
Main Results:
- Successful synthesis of novel polycationic macrocycles containing four bipyridylboronium units linked by fluorene and aryl moieties.
- Demonstration of reversible multi-step redox processes involving up to 10 electron transfers.
- Observation of switchable electrochromic behavior, with color changes correlated to computed electronic transitions.
Conclusions:
- The developed organoboronium macrocycles represent a new class of boron-based polycationic systems.
- These macrocycles exhibit significant redox activity and tunable electrochromic properties.
- The findings open avenues for designing advanced functional materials based on cationic boron chemistry.
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