光誘導銅触媒による非対称C-Oクロスカップリング

Jun Chen¹, Yu-Jie Liang², Peng-Zi Wang¹

¹CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides & Chemical Biology Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan, Hubei 430079, People's Republic of China.

Journal of the American Chemical Society

|August 11, 2021

まとめ

この研究は,オキシームエステルとダイエンを用いて炭素-酸素結合を形成するための新しい銅触媒反応を導入する. この方法は,室温で高い選択性を達成し,有機合成のための新しいツールを提供します.

科学分野:

有機化学
カタリシス
写真化学

背景:

炭素-ヘテロ原子結合の形成は有機化学において極めて重要です.
C−N結合形成の進歩は,C−O結合形成の進歩が限られている.
ラジカルを含む触媒非対称合成は活発な研究分野である.

研究の目的:

触媒による非対称C−O結合形成の方法を開発する.
簡単に手に入るオキシムエステルと1,3-ダイエンを利用する.
アリルエステルの合成において高い地域およびエナチオ選択性を達成する.

主な方法:

光誘導銅誘導クロスカップリング反応
オキシムエステルを二機能反応剤として使用する.
単一の,地球に豊富なキラル銅触媒を使用しています.
紫色発光ダイオード (LED) の照射下での室温反応
密度関数理論 (DFT) による計算研究.

主要な成果:

75以上の異なった代用性アリルエステルの合成
高い地域およびエナチオ選択性 (最大95% ee) が達成された.
フォトレドックス触媒と非対称誘導における触媒の二重作用を証明した.
ラジカル・ポラー・クロスオーバーによるπ-アリル銅中間物質を含む反応機構を提案した.

結論:

非対称なC−O結合形成のための新しく効率的な光誘導銅触媒法です
この反応は,優れた選択性を持つアリルエステルへの多用途の経路を提供します.
この発見は,触媒的非対称合成と光還元触媒の分野を前進させました.

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