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Updated: Nov 8, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Published on: September 18, 2016

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曲線型パラフェニレン単位に埋め込まれた1,3-ディラジカル:シングレット対トリプルレット状態と平面内アロマティック性

Yuki Miyazawa1, Zhe Wang1, Misaki Matsumoto1

  • 1Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.

Journal of the American Chemical Society
|April 26, 2021
PubMed
まとめ

曲線サイクロパフェニレン (CPP) の大きさは,埋め込まれた1,3ディラジカル (DR) の基本状態を決定する. 大きいDR-CPPはトリプレート状態を示し,小さいものはシングレット状態を示し,サイズに依存するスピン多重性制御を明らかにします.

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Radicals: Electronic Structure and Geometry

This lesson delves into the geometry of a radical, which is influenced by the electronic structure of the molecule. The principle is similar to that of a lone pair, where the unpaired electron influences the geometry at the radical center.
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Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
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