A Copper-Catalyzed Friedel–Crafts Alkylation/Cyclization Sequence: an Approach to Functionalized Pyrrolo[1,2‑a]indole Spirooxindoles and 9H‑Pyrrolo[1,2‑a]indoles

An efficient Cu­(OTf)2-catalyzed Friedel–Crafts alkylation/cyclizaiton sequence of 3-substituted indoles with isatin-derived oxodienes was developed, and a series of structurally complex and diverse pyrrolo­[1,2-a]­indole spirooxindoles were first obtained in up to 99% yields. This protocol proved to be quite general and was also robust for the synthesis of 9H-pyrrolo­[1,2-a]­indoles.