トリフローロメチラレンのC (sp3) -F結合をBis (NHC) ニッケル (0) 複合体を使って割る
Hiroaki Iwamoto1, Hiroto Imiya1, Masato Ohashi2
1Department of Applied Chemistry, Osaka University, Suita, Osaka 565-0871, Japan.
Journal of the American Chemical Society
|October 28, 2020
まとめ
この研究では,ニッケル ((0) コンプレックスがC ((sp3) -F結合をトリフローロメチラレンで初めて分裂することを実証した. この反応性により,これらの複雑な化合物に対する新しい触媒性水酸化法が可能になります.
科学分野:
- 有機金属化学
- フッ素化学
- カタリシス
背景:
- トリフローロメチラレンは重要な合成中間物質である.
- 強い炭素-フッ素結合の活性化は化学において重要な課題である.
- ニッケル触媒はC-Fボンドの機能化に有望な道を提供している.
研究 の 目的:
- トリフローロメチラレンのC ((sp3) -F結合がニッケル ((0) コンプレックスに初めて酸化されたことを報告する.
- トリフローロメチラレンを触媒的に水素化させる.
- C ((sp3) -F結合の裂解のメカニズムを解明する.
主な方法:
- トリフローロメチラレンとニッケル (((0) コンプレックスによるN-ヘテロサイクルカルベン (NHC) リガンドの反応.
- ニッケル (II) フッ化物の分離と特徴付け
- 水素シランを用いた触媒性水素化プロトコルの開発.
- 反応メカニズムを調査するための計算研究.
主要な成果:
- ステリカルに要求されるNHCリガンドを持つニッケル ((0)) 複合体は,トリフローロメチラレンのC ((sp3) -F結合を成功裏に割った.
- トランス- ディフローロベンジルニッケル (II) フッ化物複合体の形成が観察された.
- 水素シランを用いてトリフローロメチラレンを触媒的に水素化した.
- 計算分析により,C ((sp3) -F結合分裂のシン-SN2'メカニズムが示唆された.
結論:
- この研究は,ニッケル触媒を用いたトリフローロメチラレンにおけるC ((sp3) -F結合の活性化のための新しい方法を示している.
- 開発された水素化反応は,有価な化化合物へのアクセスのための新しい合成経路を提供します.
- この発見は,ニッケル媒介C−F結合の活性化に関するメカニズム的な洞察を提供します.
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