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Updated: May 22, 2025

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
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通过peri-substituents之间的固体排斥来非电子激活芳香框架

Annisa Indah Reza1, Nagatoshi Nishiwaki1,2

  • 1School of Engineering Science, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan. Nishiwaki.nagatoshi@kochi-tech.ac.jp.

Organic & biomolecular chemistry
|March 13, 2025
PubMed
概括

从重的替代物中对硬质的排斥会扭曲平面芳香环,导致 dearomatization 和非电子激活. 这一原理应用于1,8-二甲烯,通过素舞反应产生不对称的产物.

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All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...
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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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