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リング閉塞・エニーネ・メタテシス:モード選択性とステレオ選択性の制御
1Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|November 19, 2004
まとめ
環が閉ざされ,メタテシスは効率的にマクロサイクルを形成する. エチレン大気は,マクロサイクルダイエンの内産物およびE/Z同位体に対する選択性を改善します.
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
- 合成化学 合成化学とは
背景:
- 環閉エニンメタテシスは,マクロサイクル合成の強力なツールです.
- マクロサイクライゼーションにおける選択性を制御することは,依然として課題です.
研究 の 目的:
- リングの閉塞による10〜15個の環を合成するための選択的方法を開発する.
- エキゾー/エンドーおよびE/Z選択性に影響を与える要因を調査する.
主な方法:
- タートレート製のリンク器を用いて,一方のサブユニットと他のサブユニットを接続した.
- エチレン大気を含む様々な条件下で,環閉エニンメタテシス反応を実行した.
- リングサイズと反応条件に基づいて分析された製品の選択性.
主要な成果:
- リングのサイズは,エクソ/エンドの選択性を決定する:より大きなリング (12-15) はエンドを好み,より小さなリング (5-11) はエクソを好む.
- エチレン大気は,マクロサイクルダイエンのexo/endo選択性とE/Z選択性を大幅に改善します.
- エチレンはクロスメタテシスを誘導し,ダイエンのメタテシスを誘導し,それは高いE選択性を持つエンド製品のみを形成します.
結論:
- 環を閉じるエニネの転移は,マクロサイクルへの有効な経路です.
- エチレン大気は,この方法によってマクロサイクライゼーションにおける高い選択性を達成するために不可欠です.
- 記述された方法は,マクロサイクリックダイエンの合成を精密に制御します.
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