Ndion-H, a perfluorinated sulfonic acid resin, catalyzed the intramolecular Friedel-Crafts acylation of diarylalkane-2-carboxylic acids and arylalkanoic acids in refluxing p-xylene to provide cyclic ketones. The reactions were clean, and the water that was formed as a byproduct did not deactivate the catalyst. It was also found that the intramolecular acylation of the corresponding acid chlorides ocd under much milder reaction conditions. The ...
