Organocatalyst: No base, No solvent, No carbene

Imidazolium Salt-Catalyzed Friedel-Crafts-Type Conjugate Addition of Indoles: Analysis of Indole/Imidazolium Complex by High Level ab Initio Calculations.
Tetsuo Narumi, Seiji Tsuzuki & Hirokazu Tamamura

asian-joc

Asian J. Org. Chem., 3(4), 497-503 (2014)