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Updated: Jul 6, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
08:12

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

Published on: August 16, 2018

アレン酸エステルとケトンの有機触媒的非対称結合添加

Petteri Elsner1, Luca Bernardi, Giorgio Dela Salla

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

Journal of the American Chemical Society
|March 18, 2008
PubMed
まとめ

本研究では,キラル四分位アンモニアム塩を用いた有機触媒的エナンチオセレクティブ結合添加反応を導入しています. これらの反応は,サイクルベータケトエスターとグリシンイミンからキラルベータ,ガンマ不飽和カルボニル化合物,アルファアミノ酸誘導体を効率的に生成します.

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Conjugate Addition to α,β-Unsaturated Carbonyl Compounds

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Conjugate Addition of Enolates: Michael Addition

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α-Alkylation of Ketones via Enolate Ions

Ketones with α protons are deprotonated by strong bases like lithium diisopropylamide (LDA) to form enolate ions. The anion is stabilized by resonance, and its hybrid structure exhibits negative charges on the carbonyl oxygen and the α carbon. This ambident nucleophile can attack an electrophile via two possible sites: the carbonyl oxygen, known as O-attack, or the α carbon, known as C-attack. The nucleophilic attack via the carbanionic site is preferred. This is due to the strong interaction...
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Acid-Catalyzed Aldol Addition Reaction

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Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

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Base-Catalyzed Aldol Addition Reaction

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