α,β-不飽和カルボニル化合物の鉄触媒によるエナチオセレクティブ・ラジカル・カルボアジデーションとディアジデーション
Contact us if these videos are not relevant.
Contact us if these videos are not relevant.
PubMedで要約を見る
まとめ
この要約は機械生成です。この研究は,キラルなN,N′-二酸化物/Fe (OTf) 2触媒を用いたアルケンのエナンチオセレクティブ・ラジカルアジデーションの新しい方法を示している. このアプローチは,さらなる用途のために価値あるキラルα-アジドカルボニル化合物を効率的に合成します.
科学分野
- 有機化学
- キャタリシス
- 合成方法論
背景
- 有機アジドは有機合成の重要な構成要素である.
- エナチオセレクティブのラジカルアジデーションは,ラジカル不安定性とユニークな構造のために困難です.
研究 の 目的
- α,β-不飽和ケトンとアミドの効率的なエナンチオセレクティブ・ラジカルカルボアジデーションとダイアジデーションを開発する.
- この変換のための触媒として,キラルなN,N′-二酸化物/Fe ((OTf)) 2複合体を利用する.
主な方法
- 触媒エナチオセレクティブ・ラジカル・カーボアジデーションとディアジデーション
- キラルなN,N′-二酸化物/Fe (OTf) 2複合体を用いること.
- α,β 不飽和ケトンとアミドによる基質の範囲調査
主要な成果
- 様々なアルケンのα-アジドカルボニル誘導体の効率的な合成.
- トランスフォーメーションで良いから優れたエナチオセレクティビティを達成しました.
- チラルα-アミノケトン,ヴィチナルアミノアルコール,およびヴィチナルダイアミンの製造における製品の有用性を実証した.
結論
- 開発された方法は,エナンチオセレクティブアジデーションのための堅固な経路を提供します.
- 機構学的研究とDFT計算は,分子内移行状態を含む根本的な経路を支持する.
- この研究は,キラル窒素を含む化合物を合成するためのツールボックスを拡張します.
関連する概念動画
The method to achieve α-brominated carboxylic acids using a mixture of phosphorus tribromide and bromine is known as the Hell–Volhard–Zelinski reaction. The reaction is catalyzed by phosphorus tribromide, which can be used directly or produced in situ from red phosphorus and bromine. The mechanism comprises PBr3 catalyzed conversion of acid to acid bromide and hydrogen bromide. The acid bromide enolizes to its enol form in the presence of HBr. The nucleophilic enol attacks the...
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...
The addition of hydrogen bromide to alkenes in the presence of hydroperoxides or peroxides proceeds via an anti-Markovnikov pathway and yields alkyl bromides.
The observed regioselectivity can be explained based on the radical stability and steric effect. From the radical stability perspective, adding hydrogen bromide in the presence of peroxide directs the bromine radical at the less substituted carbon via a more stable tertiary radical intermediate. Similarly, in the steric framework, the...
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).
The ring-forming reaction occurs in two stages: Michael addition and the subsequent...
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...
Carboxylic acids react with diazomethane in an ether solvent via alkylation at the carboxylate oxygen atom to give methyl esters of the corresponding acid with excellent yields.
Diazomethane is a yellow gas having a boiling point of −23 °C. It is conveniently prepared by the action of a base on N-methyl-N-nitrosourea or N-methyl-N-nitrosotoluenesulphonamide.
The esterification mechanism involves the protonation of diazomethane by the carboxylic acid to yield a carboxylate salt and...