Rh(III)-Catalyzed Oxidative Domino C-H/N-H Annulation: Diarylureas as Arylamine Donors for the Assembly of Indolo[2,1-a]isoquinolines

An efficient and convenient Rh(III)-catalyzed double aryl C(sp2)-H bond and N-H activation and annulation reaction is reported for the synthesis of indolo[2,1-a]isoquinolines in the presence of the Cu(OAc)2 oxidant under heating conditions. Distinct from previous works with other arylamine donors, one molecule of 1,3-diarylurea can serve as a precursor of two molecules of arylamine in the reaction with diaryl-substituted alkynes.

Automated summary

An efficient and convenient method for the synthesis of indolo[2,1-a]isoquinolines was reported. This reaction involved the Rh(III)-catalyzed double aryl C(sp2)-H bond and N-H activation and annulation, with the presence of Cu(OAc)2 as the oxidant and under heating conditions. Notably, 1,3-diarylurea could serve as a precursor for the generation of two arylamine molecules, diverging from previous studies.