PIII/PV合成サイクルにおけるラウンドトリップ酸化添加,リガンドメタテシス,還元性除去
Soohyun Lim1, Alexander T Radosevich1
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|September 10, 2020
まとめ
この研究は,新しいリン酸トライアミドを用いたアリルC−F結合置換のための合成サイクルを導入する. このサイクルには,酸化添加,リガンド転移,還元性除去が含まれ,メイングループサイトで重要なメカニズム的ステップを示しています.
科学分野:
- 有機金属化学
- メイングループ 化学
- 合成有機化学
背景:
- アリルC-F結合の活性化は,合成化学における重要な課題である.
- C−F結合の機能化のための触媒サイクルの開発は,新しいフッ素化合物へのアクセスに不可欠です.
- C-X結合置換に伴う基本的なステップを理解することは,反応機構の研究に不可欠である.
研究 の 目的:
- アリルC-F置換のための合成サイクルを報告する.
- 酸化添加,リガンド転移,そしてセンターでの還元性除去のメカニズム的経路を調査する.
- アリルC-X置換のステップの完全なトライアードのよく特徴づけられた例を提供する.
主な方法:
- Cs-シンメトリックリン三酸化物の合成と特徴付け (1).
- トライアミド (1) とパーフルオアレン (ArF-F) の反応により,C-Fの酸化作用が得られる.
- DIBAL-Hを用いたリガンド転移で,P-フッ素置換剤を水化物と交換する.
- ハイドリドフォスファランの熱分解 (1·[H][ArF) で,触媒を再生し,C-Hの還元性除去を研究する.
- 反応メカニズムの解明のための実験的および計算的研究.
主要な成果:
- アリルC-F置換のための合成サイクルが,リントリアミドを用いて確立された (1).
- C-F酸化添加は,フルオロアレンと反応して,フッ素酸化素 (1·[F][ArF) を生成した.
- DIBAL-Hで生成されたヒドリドフォスファラン (1·[H][ArF) とのリガンド転移.
- ハイドリドフォスファランを加熱すると,ArF-HのC-H還元による (1) の再生が生じる.
- 実験データと計算データにより,C−Hの還元性排除の協調的だが高度に非同期的なメカニズムが確認された.
結論:
- この研究では,アリルC-F置換のための完全な合成サイクルが,主群の部位で成功裏に実証されました.
- よく特徴づけられた中間物質と製品は,アリルC-X置換の基本的なステップに関する貴重な洞察を提供します.
- この発見は,C−F結合の活性化と機能化反応のメカニズム的理解に寄与する.
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