H• 移転によって開始される根性イソメリゼーションとサイクロイソメリゼーション

Gang Li¹, Jonathan L Kuo¹, Arthur Han¹

¹Department of Chemistry, Columbia University , 3000 Broadway, New York, New York 10027, United States.

Journal of the American Chemical Society

|May 12, 2016

まとめ

水素圧下でのコバルト触媒はオレフィンをイソメライズしたり,サイクルされた製品を形成したりできます. 低コバルト H•ドナー濃度は,高ドナー濃度の他の触媒と異なり,異体化とサイクル化を促進します.

科学分野:

有機金属化学
カタリシス
有機合成

背景:

コバルト複合体は様々な有機変異の触媒として研究されている.
水素原子 (H•) 移転メカニズムは,触媒サイクルにおいて極めて重要です.
H•ドナー濃度の制御は反応経路に影響する.

研究の目的:

コバルト (II) ビス (II) ディフローロボリル) ディメチルグリオキシム複合物の触媒活性を調べる.
オレフィン変換における H•ドナー濃度の役割を明らかにする.
イソメリゼーションとサイクル化の経路を区別する.

主な方法:

Co ((II) ((dmgBF2) 2L2 (L = H2O,THF) がH2と反応する
コバルト複合体からオレフィンへの H 移転の研究
イソメリズドとサイクルされたオレフィンを含む反応製品の分析.

主要な成果:

コバルト H•ドナーの低濃度は,オレフィン異体化と循環化を促す.
ラジカル中間物質は,H•を金属に戻すか,分子内添加をすることができる.
他の触媒との高濃度のH•ドナーは,水素化と循環水素化を促進する.

結論:

コバルト H• ドナーの濃度は,オレフィン反応経路の指向における重要な要因である.
この研究は,機械的制御による選択的触媒の洞察を提供します.
コバルト複合体は,オレフィン機能化のための調整可能な反応性を提供します.

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