CuI-Catalyzed Trifluoromethylation/Cyclization Reaction of N -(2-Methylallyl)-2-arylindoles: Access to Trifluoromethylated Indolo[2,1- a ]isoquinoline (Benzo[4,5]imidazo[2,1- a ]isoquinoline) Derivatives

The copper(I)-catalyzed radical cascade trifluoromethylation/cyclization reaction of N-allyl-2-arylindoles and Togni reagent (II) was developed to achieve diverse CF₃-substituted indolo[2,1-a]isoquinoline (benzo[4,5]imidazo[2,1-a]isoquinoline) derivatives in this synthesis. The main features of this strategy include a wide substrate scope, good functional group tolerance, and moderate to good yields, which provide a valuable strategy for the synthesis of trifluoromethylated indolo[2,1-a]isoquinoline (benzo[4,5]imidazo[2,1-a]isoquinoline) derivatives.