Synthesis of 9,9‐Disubstituted 9 H ‐Pyrrolo[1,2‐ a ]indoles by Hydriodic Acid‐Catalyzed Cyclization of 1‐[2‐(1‐Aryl(or methyl)ethenyl)phenyl]‐1 H ‐pyrroles

A novel method is reported for the synthesis of 9,9‐disubstituted 9 H ‐pyrrolo[1,2‐ a ]indoles. Cyclization of 1‐[2‐(1‐aryl(or methyl)ethenyl)phenyl]‐1 H ‐pyrroles, which can be easily prepared from 2‐(1‐aryl(or methyl)ethenyl)anilines, proceeds smoothly, in general, at 0° in the presence of a catalytic (or an equimolar) amount of HI in MeCN to provide the desired products.