サイクロメタラ化鉄の識別と反応性 (II) トリアゾール誘導鉄触媒C-H活性化における中間物質
Theresa E Boddie1, Stephanie H Carpenter1, Tessa M Baker1
1Department of Chemistry , University of Rochester , Rochester , New York 14627 , United States.
Journal of the American Chemical Society
|July 16, 2019
まとめ
研究者らはトリアゾール補助C-H活性化において活性鉄種を定義した. この低スピンの鉄 (II) 複合体は,C−Hアリレーションのためのサイクロメタラート中間物質の形成に不可欠であり,有機合成を促進する.
科学分野:
- 有機金属化学
- カタリシス
- 合成有機化学
背景:
- 鉄の触媒は 有機変異の強力なツールです
- 反応性鉄種を理解することは,C-H活性化反応の開発に不可欠である.
研究 の 目的:
- トライアゾールによる鉄触媒化C-H活性化における主要なサイクル金属化鉄種を定義する.
- 鉄触媒を用いたC−Hアリレーションのメカニズムを解明する.
主な方法:
- フリーズトラップモッズバウアー光学
- シングルクリスタルX線結晶学
- 反応性研究
主要な成果:
- 活性介質は,低スピン鉄 (((dppbz) ((THF) Fe2(μ-MgX2) 複合体として識別された.
- サイクロメタラ化鉄 (II) -アリル種の形成は,ダイアリル亜鉛との反応によって起こる.
- この種の酸化により,C−Hアリレイテッド製品が得られる.
結論:
- この研究は,鉄触媒によるC−H活性化における活性化中間物の最初の直接的な実験的定義を提供する.
- 変金属化が速度決定のステップであり,C−H活性化が容易である.
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