A Chemo- and Regioselective Tandem [3 + 2]Heteroannulation Strategy for Carbazole Synthesis: Combining Two Mechanistically Distinct Bond-Forming Processes
作者:Emma Campbell、Andrea Taladriz-Sender、Olivia I. Paisley、Alan R. Kennedy、Jacob T. Bush、Glenn A. Burley
DOI:10.1021/acs.joc.1c02943
日期:2022.4.1
A modular approach to prepare tri- and tetracyclic carbazoles by a sequential [3 + 2]heteroannulation is described. First, optimization of Pd-catalyzed Buchwald–Hartwig amination followed by C/N-arylation in a one-pot process is established. Second, mechanistic analyses identified the origins of chemo- and regioselective sequential control of both bond-forming steps. Finally, the substrate scope is
描述了通过顺序 [3 + 2] 异环化制备三环和四环咔唑的模块化方法。首先,建立了在一锅法中优化 Pd 催化的 Buchwald-Hartwig 胺化,然后进行 C/N-芳基化。其次,机械分析确定了化学和区域选择性顺序控制两个键形成步骤的起源。最后,通过制备一系列三环和四环咔唑来证明底物范围,包括方便地获得几种天然产物和抗癌剂。