Regioselective Palladium-Catalyzed C-H Bond Trifluoroethylation of Indoles: Exploration and Mechanistic Insight

• DOI: 10.1021/acscatal.7b03220
• Publication Date: 2018-01-30T02:47:14Z
• Authors: Hao Zhang; Hao-Yang Wang; Yixin Luo; Chaohuang Chen; Yimiao Cao; Pinhong Chen; Yin-Long Guo; Yu Lan; Guosheng Liu
• Keywords: Oxidative addition; Functional group

A selective palladium-catalyzed trifluoroethylation reaction of indoles has been developed. The C-H bond activation process, using CF3CH2I as the fluoroalkyl source, can be employed to prepare a variety 2-CF3CH2 substituted indoles. Moreover, because it displays wide functional group tolerance, process synthesize CF3CH2-containing bioactive through late-stage trifluoroethylation. results preliminary mechanistic study and DFT calculations show that β-diketone, acting an ionic palladium ligand, plays important role in governing efficiency by accelerating oxidative addition step. In contrast, transfer indole N-H proton center is involved rate-determining