Copper-catalyzed synthesis of trifluoromethylated bis(indolyl)arylmethanes from 2-arylindoles and 2,2,2-trifluoroacetohydrazide

One-pot synthesis of trifluoromethylated bis(indolyl)arylmethanes through copper-catalyzed reaction of 2-arylindoles with 2,2,2-trifluoroacetohydrazide is described. This viable transformation provides a variety of 3,3 '-bis(indolyl)methanes with a CF3-containing tertiary carbon center in moderate to good yields. Preliminary mechanistic studies revealed that the reaction involves the in situ generation of a trifluoroacetyl radical and trapping with 2-arylindoles.