A concise and facile synthesis of 2,8-disubstituted dithieno[3,2-b:6,7-b]fluorenes starting from 2,7-dihydroxyfluorenone is reported. The key step involved is the tandem annulation–reduction of a 3,6-dichloro-2,7-di(alkynyl)fluorenone using Na2S·9H2O as a sulfur surrogate and reductant. The final dithiophene-fused fluorenes are obtained in reasonable yields (23–43%).

A new efficient synthesis of indolo[3,2,1-jk]carbazoles by the palladium-catalyzed cyclization of N-(2-bromoaryl)carbazoles is described. The reaction involves intramolecular C–C bond formation, coupled with the cleavage of a C–X bond and a C–H bond on carbazole ring. Substitutions on N-aryl core with either electron-donating or electron-withdrawing groups are introduced, and different reaction factors for cyclization are evaluated.

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.

A series of 2-amino-4-aryl-6-(9,9′-spirobifluoren-2-yl)pyrimidines have been synthesized by the reaction of guanidine and chalcones under basic conditions. The physical and optical properties indicated that these compounds generally show good blue light emissions and excellent thermal stabilities. Intermolecular hydrogen bonds and interactions have strong influences on their properties.

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.