Phenanthrene-Extended Phenazine Dication: An Electrochromic Conformational Switch Presenting Dual Reactivity
Jacopo Dosso1, Beatrice Bartolomei1, Nicola Demitri2
1Department of Chemical and Pharmaceutical Sciences, CENMAT, Centre of Excellence for Nanostructured Materials, INSTM UdR Trieste, University of Trieste, via Licio Giorgieri 1, 34127 Trieste, Italy.
Journal of the American Chemical Society
|April 12, 2022
Summary
Researchers synthesized a novel π-extended phenazine dication, revealing a distorted aromatic structure with electrochromic properties. This discovery offers potential for molecular switches and actuators in materials science.
Area of Science:
- Organic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Phenazine dications are rare, particularly those with extended π-systems.
- Understanding their structure-property relationships is crucial for developing new functional materials.
Purpose of the Study:
- To synthesize and characterize a π-extended diamagnetic phenazine dication.
- To investigate its structural, electronic, and reactive properties.
- To explore potential applications as molecular switches and actuators.
Main Methods:
- Oxidation of a phenanthrene-based dihydrophenazine precursor.
- Isolation and full characterization of the resulting dication.
- Theoretical investigations of aromaticity.
- Reactivity studies with various nucleophiles.
Main Results:
- Successful synthesis and isolation of a π-extended phenazine dication.
- Characterization revealed a distorted aromatic structure and significant electrochromic changes.
- Theoretical studies confirmed the aromaticity of the dication.
- The dication exhibited dual reactivity, leading to ring contraction or reduction.
- Reversible conformational changes upon oxidation/reduction were observed.
Conclusions:
- The study presents a rare π-extended phenazine dication with unique structural and electronic properties.
- The findings provide insights into the reactivity of dicationic polycyclic aromatic hydrocarbons.
- The reversible nature of its conformational changes suggests potential applications in molecular switches and actuators.
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