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Updated: Jun 14, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
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在表面合成和表征抗芳香循环[12]碳和循环[20]碳的化合物

Luye Sun1, Wei Zheng1, Faming Kang1

  • 1Interdisciplinary Materials Research Center, School of Materials Science and Engineering, Tongji University, Shanghai, 201804, People's Republic of China.

Nature communications
|September 2, 2024
PubMed
概括

研究人员通过表面反应合成了C12和C20反芳香环碳化合物. 他们的多基结构得到证实,C20是C20.

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The inscribed polygon method is consistent with Hückel’s 4n + 2 rule and helps to learn whether the given cyclic compound is aromatic or not. The compound is stable and aromatic if every bonding molecular orbital (MO) is completely filled with a pair of electrons. However, if the non-bonding or antibonding orbitals are filled with electrons, the compound is unstable and not aromatic. Consider the Frost circle diagrams for cycloalkenes containing 4 to 8 carbons.
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Cycloalkanes are saturated cyclic hydrocarbons with carbon atoms arranged in the form of rings. They have two fewer hydrogen atoms than the corresponding acyclic alkane; therefore, their general formula is CnH2n. The structural formulas of cycloalkanes are simplified using the line-angle representation. The regular polygons are used to represent the cycloalkane rings, with each side representing a carbon-carbon bond.
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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
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