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Updated: Jun 29, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
10:44

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

ディアニオンとテトラベンゾ[5.7]フルバレン.ディカション 比較可能なシステムにおける芳香度よりも,より高い反芳香度

Ashley M Piekarski1, Nancy S Mills, Abraham Yousef

  • 1Department of Chemistry, Trinity University, San Antonio, Texas 78212-7200, USA.

Journal of the American Chemical Society
|October 15, 2008
PubMed
まとめ

この研究では,テトラベンゾ[5.7]フルバレン・ダイアニオンとディケーションの芳香性と反芳香性を調査しています. 結果は,アロマティック系が反アロマティック系になる連続体と,その逆の連続体を示し,電子特性の洞察を提供している.

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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.
Removing one hydrogen from the intervening CH2 group with both...
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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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