インドル-2-オンのサイクル添加による (±) -コミュネシンFの総合成
Johannes Belmar1, Raymond L Funk
1Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Journal of the American Chemical Society
|September 18, 2012
まとめ
研究者らは,15ステップで (±) -communesin Fの簡潔な総合成を達成しました. 重要なサイクロアディション反応により,天然製品のテトラサイクリックコアが急速に形成され,効率的な合成戦略が示されました.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 自然製品合成 自然製品の合成
背景:
- Communesin Fは,ユニークなテトラサイクルの構造を持つ複雑な天然製品です.
- 効率的な合成経路は,そのような分子にアクセスし,研究するために不可欠です.
研究 の 目的:
- (±) -communesin F.の簡潔で効率的な総合成を開発する.
- コア構造の構築のための重要なサイクル追加ステップを確立する.
主な方法:
- 4-ブロモトリプトフォールから始まる全合成アプローチ.
- インドール-2-オンと3-(2-アジドエチル) -4-ブロモインドール間のサイクロアディション反応を利用した.
- 合成には15の線形ステップが採用されました.
主要な成果:
- (±) -communesin F.の15段階の総合合成を達成しました.
- 6.7%の総収益率を達成しました.
- サイクロアディションによる下部アミナルを含むテトラサイクリックコアの構築に成功しました.
結論:
- 開発された合成は,Fの (±) -communesinへの合理化された経路を提供します.
- 重要なサイクロアディションステップは,テトラサイクルのコアの迅速な組み立てに有効です.
- この研究は,複雑な天然製品のための合成方法論に寄与しています.
関連する概念動画
Cycloaddition Reactions: Overview
Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Robinson annulation is a base-catalyzed reaction for the synthesis of 2-cyclohexenone derivatives from 1,3-dicarbonyl donors (such as cyclic diketones, β-ketoesters, or β-diketones) and α,β-unsaturated carbonyl acceptors. Named after Sir Robert Robinson, who discovered it, this reaction yields a six-membered ring with three new C–C bonds (two σ bonds and one π bond).
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
Cycloaddition Reactions: MO Requirements for Thermal Activation
Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.
Conjugate Addition to α,β-Unsaturated Carbonyl Compounds
α,β-Unsaturated carbonyl compounds are molecules bearing a carbonyl and alkene functionality in conjugation with each other. The conjugation in the molecule leads to three resonance structures. The hybrid form exhibits two probable electrophilic sites: the carbonyl carbon and the β carbon.


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