Palladium-catalysed dearomative aryl/cycloimidoylation of indoles

The first example of dearomative palladium-catalysed isocyanide insertion reaction has been developed using functionalized isocyanides as the reaction partner of N-(2-bromobenzoyl)indoles. The imidoyl-palladium intermediate generated by tandem indole double bond/isocyanide insertion reactions could be trapped by intramolecular functional groups such as C(sp2)-H bond and alkenes, affording diversified indoline derivatives bearing C3 imine-containing heterocycles. The dearomative aryl/cycloimidoylation of indoles proceed smoothly in good to excellent yields with wide functional group tolerance.