Modern Friedel-Crafts chemistry. Part 35. New synthetic approach to substituted indolo[2,1-α][2]benzazepines and indolo[2,1-α]isoquinolines via Friedel-Crafts cyclialkylations.

Facile procedures for the construction of fused indole-containing heteropolycycles 1a-f and 2a-c have been developed. The methodology involves Friedel-Crafts cyclialkylations of heteoraryl alkanols in the presence of both Brönsted (PPA) and Lewis (AlCl3/CH3NO2) acid catalysts. The starting alkanols 6a-f and 12a-c were smoothly obtained both by reactions of the corresponding carboxylic acid esters and the corresponding ketones with Grignard reagents. Overall, this approach allows for easy and efficient access to polycyclic indoles from easily synthesized precursors. [ABSTRACT FROM AUTHOR]