Catalyst-free direct C H trifluoromethylation of indoles with Togni’s reagent

In the present study, we report the catalyst-free direct CH trifluoromethylation of electron-rich indoles in MeOH at 50 °C using Togni's reagent II as a trifluoromethylation reagent, affording the desired trifluoromethylated compounds in good yields. Furthermore, this new method is demonstrated to be useful for the trifluoromethylation of bioactive molecules melatonin and zolmitriptan, indicating its application in late-stage trifluoromethylation.