ルテニウム触媒による他のサイクロアイソメリゼーション. アリルシリルエーテルの地域選択性への影響
Barry M Trost1, Jean-Philippe Surivet, F Dean Toste
1Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|November 26, 2004
まとめ
ルテニウム触媒はエナインを効率的にサイクリングして,定義されたエノルシランを持つ5つまたは6つある新しいリングに変換します. この反応は,高いステレオコントロールを持つ多様なキラルおよびアキラル化合物へのアクセスを提供します.
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
- 合成方法論 合成方法論
背景:
- エニネは有機合成における多用途の基質である.
- ルテニウム触媒は,サイクライゼーション反応にユニークな反応性を提供します.
- エノルシランは,貴重な合成中間物質である.
研究 の 目的:
- 機能化されたエニンの新しいルテニウム触媒サイクロアイソメリゼーションの開発.
- エノールシルランを含む前例のない5つ,6つの環を合成する.
- ステレオ選択性とダイアステレオ制御に影響を与える要因を調査する.
主な方法:
- 1,6-および1,7-エニンの合成で,テルト-ブチルジメチルシリルエーテル置換剤を用いる.
- ルテニウム触媒によるサイクロアイソメリゼーションは,室温でアセトンで中性条件下で行われます.
- アルキンの置換,アルケンの幾何学,および触媒のタイプを含む反応パラメータの分析.
主要な成果:
- 効率的な形成は,幾何学的に定義されたエノールシラネスを持つ5つまたは6つ構成のリングです.
- アキラル・エニンとキラル・エニンの合成が成功しました.
- ステレオインダクションの実証により,高度に置換されたカーボ・ヘテロサイクルとヘテロサイクルが生じる.
- エノルシルランの幾何学と反応選択性に影響を与える主要なパラメータの特定.
結論:
- ルテニウム触媒によるサイクロアイソメリゼーションは,複雑なサイクル構造を構築するための効果的な方法です.
- この反応は,エノールシランの幾何学と高いダイアステレオ選択性に対する制御を提供します.
- この方法論は,価値ある合成ビルディングブロックへの簡単な経路を提供します.
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