Fluoradenes viapalladium-catalyzed intramolecular arylation

Abstract

A novel approach towards 7b-aryl-indeno[1,2,3-jk]fluorene based on a nitrogen-containing core is reported. The acid-promoted Friedel–Crafts reaction of 9-(2-bromophenyl)-9-fluorenol with carbazole, triphenylamine or triindole afforded 9-(2-bromophenyl)fluorenyl-carbazole, -triphenylamine and -triindole derivatives, which were subsequently converted to 7b-aryl-fluoradenes viapalladium-catalyzed intramolecular C–H direct arylation as a key step.