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Updated: Feb 25, 2026

Microscopic Visualization of Porous Nanographenes Synthesized through a Combination of Solution and On-Surface Chemistry
Published on: March 4, 2021
From Fenestrindane towards Saddle-Shaped Nanographenes Bearing a Tetracoordinate Carbon Atom
Wai-Shing Wong1, Chun-Fai Ng1, Dietmar Kuck2
1Department of Chemistry, State Key Laboratory of Synthetic Chemistry and Institute of Molecular Functional Materials, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Abstract:
Two saddle-shaped polycyclic aromatic compounds (8 a and 8 b) bearing an all-cis-[5.5.5.5]fenestrane core surrounded by an o,p,o,p,o,p,o,p-cyclooctaphenylene belt were synthesized and characterized by NMR spectroscopy and mass spectrometry. The key step of this synthesis involves the formation of four cycloheptatriene rings from the corresponding electron-rich 1,4,9,12-tetraarylfenestrindane derivatives 7 a and 7 b in Scholl-type cyclizations. The structural details of the D2d -symmetric saddle compound 8 a were determined by X-ray crystallography, and the properties of 8 a and 8 b were studied by UV/Vis and fluorescence spectroscopy and cyclic voltammetry.
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