Tetramethylcyclobutadiene-AlCl(3) complex reacted with bisalkynes possessing phenylene and biphenylene spacer giving rise to mono- and bis-Dewar benzenes. The rearrangement of the bis-Dewar benzene derivatives under thermal conditions (150 degrees C) yielded the corresponding linear ter- and quaterphenyl compounds possessing substituted terminal benzene rings.
A mixture of an alkynylbiphenyl and a terphenyl was also obtained by the reaction of tetramethylzirconacyclopentadiene with bisalkynylbenzene in 13% combined yield.