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Published on: March 4, 2021
Synthesis of Chrysene-Based Nanographenes by a Successive APEX Reaction
Yuichi Nakashige1, Hidefumi Nakatsuji1, Kaho Matsushima2
1Research Institute, Taoka Chemical Co., Ltd., 4-2-11 Nishhimikuni, Yodogawa-ku, Osaka 532-0006, Japan.
Researchers synthesized novel chrysene-based nanographenes (ChrNGs) using a successive annulative π-extension reaction. This method yields ChrNGs with tunable lengths and oxidation states, offering diverse photophysical properties like multicolor emission.
Area of Science:
- Organic Chemistry
- Materials Science
- Nanotechnology
Background:
- Chrysene-based nanographenes (ChrNGs) possess low energy gaps and strong fluorescence, making them promising for applications.
- Precise synthesis and limited availability hinder the widespread use of ChrNGs.
Purpose of the Study:
- To develop a novel synthetic route for chrysene-based nanographenes (ChrNGs).
- To explore the structural and photophysical diversity of ChrNGs synthesized via successive annulative π-extension (APEX).
Main Methods:
- Utilized a palladium/o-chloranil catalytic system for successive annulative π-extension (APEX).
- Employed diphenylacetylene and benzonaphthosilole as precursors.
- Incorporated exhaustive separation and cyclodehydrogenation for structural refinement.
Main Results:
- Successfully synthesized ChrNGs with varying lengths and oxidation states.
- Achieved flatter and more rigid ChrNG structures through post-synthesis modifications.
- Observed diverse photophysical properties, including intense multicolor emission, in the synthesized ChrNGs.
Conclusions:
- The successive APEX reaction provides a versatile method for synthesizing diverse ChrNGs.
- Structural control and refinement lead to tunable photophysical characteristics.
- This work expands the accessibility and potential applications of chrysene-based nanographenes.
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