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パラジウム/ノルボネン協同触媒によるディスタルアルケニルC-H機能化

Zhao Wu¹, Nina Fatuzzo¹, Guangbin Dong¹

¹Department of Chemistry , University of Chicago , Chicago , Illinois 60637 , United States.

Journal of the American Chemical Society

|January 30, 2020

まとめ

新しいパラジアム/ノルボネン触媒反応により,オリフィンの遠隔選択C−Hアリレーションが可能になる. この方法は,優れたサイト選択性を提供し,空気下で動作し,C-H機能化のための合成の可能性を拡大します.

科学分野:

有機化学
カタリシス
合成方法論

背景:

直接的なC-H機能化は,現代の合成化学の基石です.
ディスタルC−H結合活性化のための選択的方法の開発は,依然として重要な課題である.
パラジウム触媒は,C-H機能化のための多岐にわたる経路を提供します.

研究の目的:

新しい遠隔選択性アルケニルC−Hアリレーション法を開発する.
パラジウムとノルボルネン (NBE) の協同触媒をC-H活性化のために探求する.
新しい触媒システムの範囲と限界を調査する.

主な方法:

誘導パラジウム/ノルボルネン (Pd/NBE) 協同触媒システムを使用する.
最適な反応性のために適切な指向グループとNBEコカタライストを使用します.
亜循環性および循環性シスオレフィンの一連の基質を調査する.

主要な成果:

オレフィンの極度にサイト選択的なディスタルアルケニル化が達成された.
空中での反応の操作性を示した.
予備的なメカニズムの研究は,HECK経路に対するPd/NBE触媒のC-H活性化経路を支持した.
メチルヨウ酸化物とメチルブロモアセテートを用いた遠端アルキル化における最初の成功.

結論:

報告されたPd/NBE協力触媒は,遠隔選択性アルケニルC-Hアリレーションのための効果的な戦略を提供します.
この方法は,基板の範囲が広く,優れた選択性を示しています.
この研究は,遠隔のC−H機能化戦略のさらなる開発のための基礎を築いている.

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