移行金属ヒドリドからのH•移転による酸素安定化ラジカルの直接生成
Jonathan L Kuo1, John Hartung, Arthur Han
1Department of Chemistry, Columbia University , 3000 Broadway, New York, New York 10027, United States.
Journal of the American Chemical Society
|January 9, 2015
まとめ
移行金属ヒドリドは,エノールエーテルへのH•移転経由でα-アルコキシラジカルを効率的に生成します. これらのラジカルは,ダイアステロセレクティブ5エクソサイクリングを可能にし,代用されたテトラヒドロフーランへの直接的な経路を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 有機金属化学 有機金属化学
- ラジカル・ケミストリー (Radical Chemistry) とは
背景:
- 移行金属ヒドリドは,水素原子移転反応に参加することが知られている.
- エノールエーサーは,有機合成における多用途の基質である.
- α-アルコキシラジカルの生成と反応性は,合成アプリケーションに興味があります.
研究 の 目的:
- 移行金属ヒドリド (CpCr(CO) 3H からエノールエーテル (n-ブチルビニルエーテル) への H• 移転を調査する.
- 生成されたα-アルコキシラジカルの後の化学的性質を研究する.
- 代用テトラヒドロフーランを合成する際にこれらのラジカルの有用性を調査する.
主な方法:
- H• 移転の速度定数を決定するための運動測定.
- 反応経路と生成されたラジカルの産物の検討.
- サイクライゼーションプロセスのダイアステレオ選択性の分析.
主要な成果:
- CpCr(CO) 3H から n-ブチルビニルエーテルへの H• 移転の速度定数を測定した.
- この方法によって生成されるα-アルコキシラジカルは,5-エクソサイクリングをします.
- サイクライゼーションは,同類の全炭素ラジカルと比較して,より高いダイアステロセレクティブ性を示します.
結論:
- 移行金属ヒドリド媒介のH•移転は,α-アルコキシラジカルを生成するための効果的な方法である.
- これらのラジカルは,置換されたテトラヒドロフーランへの容易かつダイアステレオ選択的な経路を提供します.
- この方法論は,複雑なサイクルエーテルを合成するための貴重なツールを提供します.
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