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Updated: Feb 21, 2026

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
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エレクトロフィリック・アロマティック・サブスティチュエーションにおけるサブスティチュエント・エフェクトをオーバーライドする

Liangyu Guan1, Maxwell Gargiulo Holl1, Cody Ross Pitts1

  • 1Department of Chemistry, Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States.

Journal of the American Chemical Society
|October 11, 2017
PubMed
まとめ

電子欠乏の芳香輪は,新しい水素結合相互作用により,予期せぬほど,電子が豊富なものよりも速く反応する. このHO-アレンの活性化は,非活性化を克服し,電友芳香置換 (EAS) 反応における好ましい置換と強化された反応性を可能にします.

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In an electrophilic aromatic substitution reaction, an electrophile substitutes for a hydrogen of an aromatic compound.
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Simple aryl halides do not react with nucleophiles. However, nucleophilic aromatic substitutions can be forced under certain conditions, such as high temperatures or strong bases. The mechanism of substitution under such conditions involves the highly unstable and reactive benzyne intermediate. Benzyne contains equivalent carbon centers at both ends of the triple bond, each of which is equally susceptible to nucleophilic attack. This 50–50 distribution of products is...
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All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for...
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