Elecrophilic Substitution of Indoles: Part XI. Lewis Acid Induced Reaction of Skatole with Bezil

The electrophilic substitution of 3-methylindole with benzil in the presence of BF 3 .Et 2 O resulted in a novel heterocyclic system incorporating a stable boron difluoride chelate. The structure was established from spectral analysis ( 1 H-, 13 C-, 11 B-, 19 F-nmr) and X-ray crystallographic analysis