カタリティック・レジオセレクティブ・オレフィン・ヒドロアリレーション (アルケニル化)
Chen-Fei Liu1, Xiaohua Luo1,2, Hongyu Wang1
1Department of Chemistry, National University of Singapore, 4 Science Drive 2, Singapore, 117544, Republic of Singapore.
Journal of the American Chemical Society
|June 21, 2021
まとめ
この研究では,オレフィンの水酸化とアルケニル化のための新しい触媒法が導入され,複雑な分岐構造が生成されます. この新しいニッケル触媒反応は 価値ある化学化合物への高度に選択的で効率的な経路を提供する.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- アルケンの炭化水素機能化は有機合成において極めて重要です.
- 活性化されていないオレフィンとの分岐選択反応は困難です.
- 既存の二重触媒方法は,しばしば金属ヒドリド原子移転 (MHAT) を含む.
研究 の 目的:
- 非活性化および活性化オレフィンのマルコフニコフ選択的水酸化/アルケニル化のための新しい触媒システムを開発する.
- アリルとアルケニルで置換された三次および四次中心を形成する際の高収量と地域選択性を達成する.
- 反応メカニズムを明らかにし,以前のMHAT依存の経路と区別する.
主な方法:
- 触媒として二次元Ni (I) コンプレックスを使用する.
- ハイドリッドの源として外因的なアルコキシド基を使用する.
- オレフィンと反応するオーガノブロミドやトリフラート (フェノールやケトンから)
主要な成果:
- 様々なオレフィンのマルコヴニコフ選択的水酸化/アルケニル化が達成された.
- アリルおよびアルケニル置換の三次および四次中心を持つ分離された製品,最大95%の収量.
- 99:1以上の比率で優れた地域選択性を得ました.
- 機械学的研究は,炭基化に伴う非根性経路と,その後ヒドリドの移転を示した.
結論:
- アルケンの炭化水素機能化のための新しい,効率的で高度に選択的な単一触媒プロトコルが確立されています.
- この方法は,金属水素原子の移転を避け,異なる非過激なメカニズムを介して進みます.
- このプロトコルは 医学的に重要な骨組みを 合成する有用性を示しています
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