サイクリックラセミクスタートマテリアルによるCu触媒による非対称性アリルアルキル化に関するメカニズム研究
Emeline Rideau1, Hengzhi You1, Mireia Sidera1
1Department of Chemistry, Chemistry Research Laboratory, University of Oxford , 12 Mansfield Road, Oxford, OX1 3TA, U.K.
Journal of the American Chemical Society
|April 1, 2017
まとめ
銅の触媒は,複雑なオリゴメリック種を形成することによって,アリルハリドの非対称な添加を容易にする. これらの触媒は,出発材料をラセミズし,ダイナミックな運動非対称変換のために選択的に1つのエナチオメールを生成します.
科学分野:
- 有機金属化学
- 非対称な触媒
背景:
- 銅で触媒化された非対称反応は,キラル分子を合成するために不可欠です.
- これらの反応のメカニズム,特に動的運動非対称変換を理解することは,新しい触媒システムの開発の鍵です.
研究 の 目的:
- ラセミアルリック電ophilesにCu-触媒化非対称添加のメカニズムを明らかにする.
- カタリシスにおけるオリゴメリック銅-リガンド複合体とカウンターイオンの役割を調査する.
- 新しい反応条件とリガンドを開発し,エナチオ選択性と基板の範囲を改善する.
主な方法:
- 同位体ラベリング,NMRスペクトロスコーピー (運動およびダイナミック),運動モデリングを含むメカニズム研究.
- 構造-活性関係分析と新しいフォスフォラミド酸リガンドの開発.
- アリルヨーデットとアリル塩化物の中間物質の調査
主要な成果:
- オリゴメリックCu-リガンド複合体は反応中に進化し,速度とエナチオ選択性を高めます.
- Cu- counterionsは,アルリルヨウ素中介物質を通じて経路の選択とラセミゼーションに影響を与えます.
- 新しいリガンドDは,ラセミックアリルリン酸塩酸と7連鎖環アリル塩化物への高度なエナンチオセレクティブ添加を可能にします.
結論:
- 提案されたメカニズムは,基質をラセミズし,高いエナチオ選択性を達成する複雑なオリゴメリック触媒を含む.
- この研究は,より広範なダイナミック運動非対称変換の開発の洞察を提供します.
- この発見は,銅触媒による非対称反応の拡張を容易にする見込みである.
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