钯催化N-磺酰基吲哚衍生物碳-氢键芳基化反应

Pd-catalyzed C-H arylation of N-sulfonyl indole derivatives

摘要:

以碘代芳烃为芳基化试剂, 论文详细探讨了N-对甲苯磺酰基吲哚通过磺酰基团导向的钯催化碳-氢键选择性芳基化反应过程. 研究结果表明, 以醋酸钯为催化剂、三苯基膦为配体、碳酸钠为碱和碳酸银为添加剂，N-对甲苯磺酰基吲哚在1,4-二氧六环为溶剂中于120 ℃下反应24小时可获得2位和7位芳基化的产物，反应总收率可达到93%。在此标准条件下, 通过改变底物和碘代芳烃结构，研究了该合成方法的适用范围与局限性, 制备得到的28种芳基化吲哚衍生物，总产率变化范围在22%~93%之间，经1H NMR、13C NMR 和 HRMS 表征确定了其化学结构。关键词：钯催化；吲哚骨架；C-H官能化；芳基化；导向基团中图分类号：TQ426；O641.4 文献标识码： A 文章编号：

Abstract:

Using iodoarenes as arylation reagents, Pd-catalyzed sulfonyl group-directed selectively C-Harylation of indoles was investigated in detail. The results showed N-tosyl indole can be converted into 2- and 7-arylated products with an overall yield of 93% in 1, 4-dioxaneat 120 ℃for 24 h with Pd(OAc)2/PPh3 as the catalyst, Na2CO3 as the base and Ag2CO3 as the additive. Under these optimized conditions, the scope and limitation of the synthetic method were examined by using different aryl iodides to obtain 28 indole-based compounds in 22%~93% total yields, and the structure of corresponding indole products were elucidated by 1H NMR, 13C NMR and HRMS spectra.