ディエンアミンのカタリシス:アルファ,ベータ不飽和アルデヒドの有機触媒的非対称ガンマアミネーション

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Updated: Jul 15, 2026

Achieving Moderate Pressures in Sealed Vessels Using Dry Ice As a Solid CO2 Source
06:26

Achieving Moderate Pressures in Sealed Vessels Using Dry Ice As a Solid CO2 Source

Published on: August 17, 2018

Søren Bertelsen1, Mauro Marigo, Sebastian Brandes

  • 1The Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark.

Journal of the American Chemical Society
|September 28, 2006
PubMed
まとめ

この研究では,不飽和アルデヒドの直接非対称的なガンマアミナ化のための新しい有機触媒法が導入されています. 二次アミンは,この反応を可能にし,様々な基板に対して高いエナントオ選択性を達成します.

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Acid-Catalyzed α-Halogenation of Aldehydes and Ketones

By replacing an α-hydrogen with a halogen, acid-catalyzed α-halogenation of aldehydes or ketones yields a monohalogenated product
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
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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 the...
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Diazonium Group Substitution: –OH and –H

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Aryldiazonium Salts to Azo Dyes: Diazo Coupling

The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
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1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism

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