Xu Guo-Qiang, Xu Ji-Tao, Feng Zhi-Tao, Liang Hui, Wang Zhu-Yin, Qin Yong, Xu Peng-Fei
State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China.
Institute of Nanoscience and Nanotechnology, School of Physical Science and Technology, Lanzhou University, Lanzhou, 730000, P. R. China.
Angew Chem Int Ed Engl. 2018 Apr 23;57(18):5110-5114. doi: 10.1002/anie.201710523. Epub 2018 Mar 23.
Herein we describe a mild method for the dual C(sp )-H bond functionalization of saturated nitrogen-containing heterocycles through a sequential visible-light photocatalyzed dehydrogenation/[2+2] cycloaddition procedure. As a complementary approach to the well-established use of iminium ion and α-amino radical intermediates, the elusive cyclic enamine intermediates were effectively generated by photoredox catalysis under mild conditions and efficiently captured by acetylene esters to form a wide array of bicyclic amino acid derivatives, thus enabling the simultaneous functionalization of two vicinal C(sp )-H bonds.
在此，我们描述了一种温和的方法，通过顺序可见光光催化脱氢/[2+2]环加成过程，实现饱和含氮杂环的双C(sp³)-H键官能团化。作为对已成熟的亚胺离子和α-氨基自由基中间体使用方法的补充，难以捉摸的环状烯胺中间体在温和条件下通过光氧化还原催化有效生成，并被乙炔酯有效捕获，形成了一系列双环氨基酸衍生物，从而实现了两个相邻C(sp³)-H键的同时官能团化。
