アルケノールとオレフィン/アルキンからの機能化されたテトラヒドロフーランは,エアロビック酸化-ラジカル添加カスケード経由で発生する
Patrick Fries1, Daniel Halter, Alexander Kleinschek
1Fachbereich Chemie, Organische Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Strasse, D-67663 Kaiserslautern, Germany.
Journal of the American Chemical Society
|February 26, 2011
まとめ
ビショモアリルアルコールのコバルト触媒による有酸素酸化は,循環するラジカルを生成します. これらのラジカルは,様々な不飽和化合物によって捕らえられ,ステレオ選択的酸化添加カスケードを通じて代用テトラヒドロフーランを生成する.
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
- 合成方法論 合成方法論
背景:
- ビショモアリルアルコールは,有機合成における汎用的な前駆体である.
- 代替テトラヒドロフーランを合成するための効率的な方法の開発は極めて重要です.
- ラジカルサイクライゼーション反応は,サイクリック化合物への強力な経路を提供します.
研究 の 目的:
- テトラヒドロフラン合成のための新しい有酸素酸化添加カスケードを開発する.
- 置換テトラヒドロフーランのステレオ選択的形成を調査する.
- 開発された方法論の範囲と限界を調査する.
主な方法:
- コバルト (II) 触媒を用いたアルキルおよびフェニル置換4-ペンテノールのエアロビック酸化.
- γ-テルピネンやサイクロヘキサ-1,4-ディエネのような酸化物質の存在下でコバルト複合体によって媒介される過激なサイクル化.
- 様々なオレフィンやアルキンでサイクリストラジカルを捕まえる.
主要な成果:
- テトラヒドロフーリルメチル基のステレオ選択的形成.
- 多様なミカエル受容体とアルキンでラジカルを成功裏に捕まえる.
- 定義されたステレオ化学 (2,3-トランス,2,4-シス,2,5-トランス) を有する二および三置換テトラヒドロフーランの合成.
- 多段階のカスケードによるダイアステロエーマー的に純粋なビステラヒドロフランの調製.
結論:
- 開発された有酸素酸化添加カスケードは,ステレオ定義のテトラヒドロフーランへの効率的な経路を提供します.
- この方法は,様々な基板に適用でき,その汎用性を実証しています.
- このアプローチは,複雑なヘテロサイクリック・スキャファードを構築するための貴重なツールです.
関連する概念動画
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