In continuing our program's2 of developing catalytic methods for the synthesis of heterocycles it was decided to investigate the method reported for indole in a recent patent by Gresham and Br~ ner.~ They reported the dehydrocyclization of o-ethylaniline to indole by means of a titania gel catalyst at temperatures of 550 to 750'. These investigators make no mention of attempts to extend this unique synthesis to other indoles. Although previous ...
