水溶液中のアリファ酸カルボキシル酸の銀触媒によるデカルボキシル活性フローリネーション
Feng Yin1, Zhentao Wang, Zhaodong Li
1Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, PR China.
Journal of the American Chemical Society
|June 15, 2012
まとめ
この研究では,酸化化合物を生成するための新しい方法が紹介されています. これは,炭酸塩酸の化を触媒化するために銀酸塩を使用し,穏やかな条件下でアルキルフッ素を効率的に生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- フロアンの化学的性質
背景:
- フッ素化合物は,様々な産業において不可欠である.
- 炭素-フッ素結合の形成は,特に特定の場所では依然として困難です.
研究 の 目的:
- アルキルフッ素を合成するための効率的かつ実用的な方法を開発する.
- C(sp(3)) -F結合形成のための新しい触媒的アプローチを探求する.
主な方法:
- 銀酸ナトリート (AgNO(3) を触媒として利用する.
- SELECTFLUOR®をフッ化剤として使用しています.
- 反応を温和な条件下で水溶液で実施する.
主要な成果:
- 様々なアリファ酸カルボキシル酸の効率的なデカルボキシル法による化が達成された.
- 適切なアルキルフッ素を合成し,満足のいく収量を得ました.
- 方法の汎用性,化学選択性,機能群互換性を実証した.
結論:
- 開発されたラジカル・フッ素化方法は,フッ素化分子を合成するために非常に実用的です.
- 提案されたメカニズムは,Ag (III) 媒介による単一の電子移転とフッ素原子移転を含む.
- この触媒性フルオロデカルボキシル化が,有機合成のための貴重なツールである.
関連する概念動画
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...
01:14α-Halogenation of Carboxylic Acid Derivatives: Overview
Unlike aldehydes and ketones, carboxylic acids do not readily participate in α halogenation reactions via enols or enolate intermediates. However, α-halogenated acids are obtained through other methods. One of the approaches is the Hell–Volhard–Zelinsky (HVZ) reaction, wherein the carboxylic acid is treated with halogen in the presence of PBr3. It involves the conversion of acid to acid halide, which exists in equilibrium with its enol form. The enol attacks the electrophilic halogen to produce...
01:13Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Mechanism
Carboxylic acids react with alcohols to yield esters via an acid-catalyzed condensation reaction called Fischer esterification. This is a nucleophilic acyl substitution reaction that proceeds via a tetrahedral intermediate, where a water molecule is eliminated as the leaving group.
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...
01:19Preparation of Carboxylic Acids: Hydrolysis of Nitriles
Nitriles (R–CN) can be converted into carboxylic acids (R–COOH) upon treatment with aqueous acids, i.e., upon hydrolysis of nitriles. Under base-catalyzed conditions, carboxylate anions (R–COO−) are formed.
01:17Carboxylic Acids to Primary Alcohols: Hydride Reduction
Carboxylic acids, upon reaction with strong reducing agents such as lithium aluminum hydride followed by hydrolysis, undergo reduction to form primary alcohols.