触媒的な炭素-炭素シグマ結合活性化:アシルキノリンによる分子内カーボアシレーション反応
Ashley M Dreis1, Christopher J Douglas
1Department of Chemistry, University of Minnesota-Twin Cities, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|December 25, 2008
まとめ
この研究は,炭素-炭素シグマ結合の活性化のための新しいロジウム触媒反応を導入しています. 新しいアルケンの炭酸塩酸化法では,合成化学で価値のある,複雑な全炭素四次中心を効率的に生成します.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- 合成有機化学 合成有機化学について
背景:
- 炭素-炭素シグマ結合の活性化は,現代化学における重要な課題です.
- C-C結合の機能化のための効率的な触媒的方法の開発は,複雑な有機分子を合成するために不可欠です.
研究 の 目的:
- 炭素-炭素シグマ結合の直接活性化のための新しい触媒システムを開発する.
- 全炭素四分中心の構築のための新しいアルケンの炭酸酸化反応を確立する.
主な方法:
- クイノリン誘導,ロジウム誘導のC-Cシグマ結合活性化を使用した.
- 反応範囲を実証するために,幅広い基板を使用しました.
主要な成果:
- 新しいアルケンの炭酸酸化反応を成功裏に開発した.
- 良質から優れた収穫量を持つ全炭素四次中心の建設を達成しました.
- 様々なカーボサイクリックおよびヘテロサイクリックリングシステムへのアクセスが実証されています.
結論:
- 開発されたロジウム触媒アルケンの炭酸酸化は,C-Cシグマ結合の活性化に有効な方法である.
- この反応は,複雑な分子構造,特に四次炭素中心を含む分子構造を合成するための強力なツールとなります.
関連する概念動画
01:15Nucleophilic Acyl Substitution of Carboxylic Acid Derivatives
Nucleophilic acyl substitution is an important class of substitution reactions involving a nucleophile and an acyl compound, such as carboxylic acids and their derivatives. In these reactions, the leaving group attached to the acyl group is substituted by a nucleophile. The general mechanism proceeds via two steps.
01:41Reactions of Carboxylic Acids: Introduction
Carboxylic acids possess an acidic –COOH functional group. The acidity can be attributed to the resonance stabilization of their conjugate base, wherein the negative charge is delocalized over both oxygen atoms.
01:01Acid Halides to Carboxylic Acids: Hydrolysis
Hydrolysis of acid halides is a nucleophilic acyl substitution reaction in which acid halides react with water to give carboxylic acids. The reaction occurs readily and does not require acid or a base catalyst.
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...
01:21Acid-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...
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...
01:13Preparation of Carboxylic Acids: Carboxylation of Grignard Reagents
Carboxylic acids can be prepared by the carboxylation of Grignard reagents (RMgX). This method is convenient for converting alkyl (primary, secondary or tertiary), vinyl, benzyl, and aryl halides to carboxylic acids with one additional carbon than the starting RMgX.
01:27Vicinal Diols via Reductive Coupling of Aldehydes or Ketones: Pinacol Coupling Overview
Wilhelm Rudolph Fittig discovered the pinacol coupling reaction in 1859. It is a radical dimerization reaction and involves the reductive coupling of aldehydes or ketones in the presence of hydrocarbon solvent to yield vicinal diols.