Cu-Catalyzed [4 + 1] Annulation toward Indolo[2,1-a]isoquinolines via Oxidative C(sp3)/C(sp2)-H Bond Bifunctionalization

Tian-Shu Zhang, Qi Zhao, Wen-Juan Hao, Shu-Jiang Tu,* Bo Jiang*

A new Cu-catalyzed [4 + 1] annulation of N-aryl-1,2,3,4-tetrahydroisoquinolines (N-aryl THIQs) with α-diazoketones has been established under oxidative conditions, leading to the construction of a series of indolo[2,1-a]isoquinolines with generally good yields. The reaction enables dediazotized dicarbonylation of α-diazoketones, making direct C(sp³)/C(sp²)-H bond bifunctionalization to access tetracyclic aza-heterocyclic skeletons.

Chem. Asian. J. 2019, 14, 1042-1049