Tan Linbo, Xu Teling, Zhang Xueyan, Luo Juan, Xiao Xiaoqin, Li Lian, Huang Shanshan, Tang Qiang
College of Pharmacy, Children's Hospital, Chongqing Medical University, Chongqing 400016, People's Republic of China.
College of Pharmacy, Chongqing Medical University, Chongqing 400016, People's Republic of China.
Org Lett. 2023 Apr 21;25(15):2600-2605. doi: 10.1021/acs.orglett.3c00554. Epub 2023 Apr 5.
Reported here is an efficient Friedel-Crafts-type reaction followed by electrocyclization cascade under an air atmosphere, employing readily available building blocks as starting materials, ethanol as a solvent, and Brønsted acid as a catalyst. On the basis of the cascade strategy, 2-(2-aminophenyl)-9-carbazole has been furnished with excellent regioselectivity, exceptional functional group tolerance, and tolerated large-scale synthesis. Furthermore, one-pot syntheses of quino[3,4-]carbazoles have been accomplished, demonstrating the broad synthetic utility of this strategy in the synthesis of valuable heteroaryl-annulated []carbazoles.
本文报道了一种高效的傅克型反应，随后在空气气氛下进行电环化串联反应，使用易于获得的结构单元作为起始原料，乙醇作为溶剂，布朗斯特酸作为催化剂。基于串联策略，2-(2-氨基苯基)-9-咔唑具有优异的区域选择性、出色的官能团耐受性，并可进行大规模合成。此外，还实现了喹啉并[3,4-]咔唑的一锅法合成，证明了该策略在合成有价值的杂芳基稠合咔唑方面具有广泛的合成用途。
