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Updated: May 10, 2026

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
07:30

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

酸化窒素とN-ヘテロサイクルカルベンの誘導体:合成,構造,反応性

Alexander G Tskhovrebov1, Basile Vuichoud, Euro Solari

  • 1Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.

Journal of the American Chemical Society
|June 14, 2013
PubMed
まとめ

N-ヘテロサイクリックカルベン (NHCs) は,室温で酸化窒素 (N2O) と添加物を容易に形成します. これらのアダクトは,異なる熱安定性と反応性を示し,N2Oの活性化と協調化学の洞察を提供します.

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meta-Directing Deactivators: –NO2, –CN, –CHO, –⁠CO2R, –COR, –CO2H

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 the...
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ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3

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One of the common methods to prepare nitriles is the dehydration of amides. This method requires strong dehydrating agents like phosphorous pentoxide or boiling acetic anhydride for converting amides to nitriles. Another reagent namely, thionyl chloride also accomplishes the dehydration of amides, where amide acts as a nucleophile. The first step of the mechanism involves the nucleophilic attack by the amide on the thionyl chloride to form an intermediate. In the next step, the electron pairs...
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Electrophilic Aromatic Substitution: Nitration of Benzene

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