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Published on: March 4, 2021
Axially Chiral Nonbenzenoid Nanographene with Second Harmonic Generation Property
Liyuan Qin1,2, Jin Xie3, Botao Wu4
1Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Researchers developed a novel axially chiral nonbenzenoid nanographene, a unique optoelectronic material. This new compound exhibits long-wavelength circular dichroism and second harmonic generation properties, expanding the scope of chiral nanographene applications.
Area of Science:
- Organic Chemistry
- Materials Science
- Nanotechnology
Background:
- Chiral nanographenes (NGs) are promising optoelectronic materials.
- While helically chiral NGs are well-studied, axially chiral examples, especially nonbenzenoid ones, are rare.
Purpose of the Study:
- To report the first synthesis of an axially chiral nonbenzenoid nanographene.
- To investigate its chiroptical and nonlinear optical properties.
Main Methods:
- Synthesis via palladium-catalyzed aryl silane homocoupling.
- Chiral high-performance liquid chromatography (HPLC) for enantiomer separation.
- Circular dichroism (CD) and second harmonic generation (SHG) measurements.
Main Results:
- Successful synthesis of a novel axially chiral nonbenzenoid nanographene (2) with high atropisomeric stability.
- Demonstrated CD activity up to 660 nm, indicating strong chiroptical response.
- Racemic 2 forms a chiral crystal lattice exhibiting SHG, and enantiomers show SHG-CD properties.
Conclusions:
- This work introduces a new class of axially chiral nonbenzenoid nanographenes.
- The synthesized compound exhibits unique optical properties, including long-wavelength CD and SHG.
- These findings open new avenues for designing advanced chiral optoelectronic materials.
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