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銀触媒による線形アルカンのカルベン制御地域選択的機能化

María Álvarez¹, Francisco Molina¹, Pedro J Pérez¹

¹Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, CIQSO-Centro de Investigación en Química Sostenible and Departamento de Química, Universidad de Huelva, 21007 Huelva, Spain.

Journal of the American Chemical Society

|December 13, 2022

まとめ

研究者らはアルケンのC−H結合を機能化するための新しい銀触媒方法を開発した. このアプローチでは,特定の銀複合体とダイアゾ反応剤を使用して,地域選択性を制御し,主または二次部位の選択的修正を可能にします.

科学分野:

有機化学
カタリシス
C-H 機能化

背景:

アルケンのC-H機能化の制御は,典型的には触媒に依存し,しばしば特定のダイアゾ反応剤を伴うロジウム触媒を使用する.
既存の方法は主に反応の結果を決定する触媒に依存している.

研究の目的:

線形アルカンの地域選択的C−H機能化のための代替戦略を提示する.
ダイアゾ反応剤によって制御される,触媒独立の地域制御を実証する.

主な方法:

トリスピラゾリルボレートリガンドを触媒として使った銀複合体.
ドナー-受容体アリルディアゾアセテートと受容体エチルディアゾアセテートを含む様々なダイアゾ反応剤を使用した.
ヘクサンやペンタンのような線形アルカンの機能化を調べた

主要な成果:

達成された地域選択は主に触媒ではなくダイアゾ反応剤によって制御される.
ドナー-受容体アリルディアゾアセテートは,選択的に二次C-H結合を機能させた.
エチルディアゾアセテート受容体は,前例のないC−H結合の機能化を達成した.

結論:

ダイアゾ化合物によるC-H機能化のための新しい銀触媒システムを開発した.
触媒ではなくダイアゾ反応剤がアルカン機能化における地域選択性を決定することが示された.
主要または二次的なサイトで機能化を制御することによって,選択的なアルカンの改変のための新しい道を開きました.

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