Pd-Catalyzed Direct C7 Trifluoromethylation of Indolines with Umemoto’s Reagent

• DOI: 10.1021/acs.orglett.3c04123
• Publication Date: 2024-01-30T04:12:44Z
• Authors: Qinglang Song; Lin Zhang; Bin Wang; Ziren Chen; Weiwei Jin; Yu Xia; Shaofeng Wu; Chenjiang Liu; Yonghong Zhang

An efficient palladium-catalyzed region-selective C7-trifluoromethylation of indolines using commercially available Umemoto's reagent was reported. The reaction utilizing Umemoto's reagent as CF3 radical precursor, pyrimidine as a removable directing group, Pd(II) as a catalyst, and Cu(II) as an oxidant furnished the required products with excellent regioselectivities and good yields. The present strategy has good region-selectivity, broad substrate scope, and scale-up application. Additionally, the present method was underlined by the direct C-1 trifluoromethylation of carbazoles. Furthermore, C7 trifluoromethylated indole can also be easily obtained via Pd-catalyzed direct C-7 trifluoromethylation/oxidation/deprotection sequential reactions.