アルケニラーゼアレンとケトンとのエナチオセレクティブ銅触媒還元結合
Aakarsh Saxena1, Bonnie Choi, Hon Wai Lam
1EaStCHEM, School of Chemistry, University of Edinburgh, United Kingdom.
Journal of the American Chemical Society
|May 9, 2012
まとめ
この研究は,キラルアザアレン化合物を生成するための新しい触媒方法を示しています. アルケニラザレネとケトンのエナチオセレクティブ・リダクティブ・カップリングにより,高い選択性を持つ有価なアロマティック・ヘテロサイクルが得られます.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- アシンメトリック・シンセシス
背景:
- チラルアザレンの化合物は,医薬品化学と材料科学における重要な構成要素である.
- これらの化合物の効率的なエナチオセレクティブ合成方法を開発することは,依然として大きな課題です.
研究 の 目的:
- キラルアザレンを含む化合物の合成のための新しい触媒エナンチオセレクティブ法を開発する.
- 銅ヒドリド触媒を用いたアルケニラザレンのケトンとの還元結合を調査する.
主な方法:
- エナチオセレクティブ・リダクティブ・カップリング反応を促進するために,銅水化物触媒を用いた.
- 隣接するアルケンを活性化するために,CNを含むアザアレンを使用し,核愛性添加を行う.
- 様々なアザアレンとケトンに対する反応の耐性を調査した.
主要な成果:
- アルケニラゼアレンとケトンのエナチオセレクティブ・リダクティブ・カップリングを成功裏に開発した.
- この方法により,アロマティックヘテロサイクルは,三次アルコールを含有するサイドチェーンを得られる.
- 製品において高いレベルのダイアステレオ選択性とエナチオ選択性を達成した.
結論:
- 開発された触媒的方法は,キラルアザレンを含む化合物への貴重な経路を提供します.
- このプロセスは,幅広い基板範囲と優れたステレオ制御を示しています.
- このアプローチは,複雑なヘテロサイクリック分子の非対称合成のためのツールキットを拡張します.
関連する概念動画
01:19α-Hydroxy Ketones via Reductive Coupling of Esters: Acyloin Condensation Overview
The pinacol and McMurry reactions involve the reductive coupling of ketones or aldehydes. Similarly, the bimolecular reductive coupling of two ester molecules in the presence of sodium metal in an aprotic solvent yields an α-hydroxy ketone product. The α-hydroxy ketone is also called acyloin, so the reaction is referred to as ‘acyloin condensation.’
01:10α-Alkylation of Ketones via Enolate Ions
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01:22Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
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01:14Acid Halides to Ketones: Gilman Reagent
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As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen double...
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen double...
01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
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.