Li Longji, Li Yao, Fu Niankai, Zhang Long, Luo Sanzhong
Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Angew Chem Int Ed Engl. 2020 Aug 17;59(34):14347-14351. doi: 10.1002/anie.202006016. Epub 2020 Jul 8.
Asymmetric catalysis with benzyne remains elusive because of the highly fleeting and nonpolar nature of benzyne intermediates. Reported herein is an electrochemical approach for the oxidative generation of benzynes (cyclohexyne) and its successful merging with chiral primary aminocatalysis, formulating the first catalytic asymmetric enamine-benzyne (cyclohexyne) coupling reaction. Cobalt acetate was identified to stabilize the in situ generated arynes and facilitate its coupling with an enamine. This catalytic enamine-benzyne protocol provides a concise method for the construction of diverse α-aryl (α-cyclohexenyl) quaternary carbon stereogenic centers with good stereoselectivities.
由于苯炔中间体具有高度瞬态和非极性的性质，苯炔的不对称催化仍然难以实现。本文报道了一种电化学方法，用于氧化生成苯炔（环己炔），并成功地将其与手性伯胺催化相结合，构建了首例催化不对称烯胺-苯炔（环己炔）偶联反应。已确定醋酸钴可稳定原位生成的芳炔，并促进其与烯胺的偶联。这种催化烯胺-苯炔反应方法为构建具有良好立体选择性的各种α-芳基（α-环己烯基）季碳立体中心提供了一种简洁的方法。
