The novel polysubstituted 1,1′-phenylene-bipyrrole compounds were synthesized by the double [3+2] cycloaddition-extrusion reactions of N,N′-phenylene-bimünchnones and dimethyl acetylenedicarboxylate in dry toluene at 80 °C for 24 h. Bimünchnones were prepared successfully by cyclodehydration reactions of N,N′-biacyl-N,N′-(1,4-phenylene)-bis(2-arylglycine) with N,N′-diisopropylcarbodiimide in dry toluene at 0–5 °C for 1.5 h. The structures of the products were characterized on the basis of spectral data.

The reaction of tetraarylbutatrienes (tetraaryl[3]cumulenes) with tetracyanoethene (TCNE), a strong electron-accepting molecule, at room temperature yielded novel four-membered ring compounds (head-to-tail unsymmetrically substituted diarylallene dimers) by [2 + 2] cycloaddition of the central CC bond of the butatrienes. This reaction proceeded through a head-to-head symmetrically substituted diarylallene dimer intermediate. Unsymmetrical butatriene also formed a small amount of another head-to-tail dimer. Although the allene dimer is stable in nonpolar solvents, it converts to other bicyclic and tricyclic compounds in MeOH or CH3CN at room temperature.

Tetraphenyl[5]cumulene (tetraphenylhexapentaene) underwent cyclotrimerization in refluxing toluene for 10–15 min to give a tricyclodecadiene derivative in 68% yield.

The reaction of tetraarylbutatrienes (tetraaryl[3]cumulenes) with tetracyanoethene (TCNE), a strong electron-accepting molecule, at room temperature yielded novel four-membered ring compounds (head-to-tail unsymmetrically substituted diarylallene dimers) by [2 + 2] cycloaddition of the central CC bond of the butatrienes. This reaction proceeded through a head-to-head symmetrically substituted diarylallene dimer intermediate. Unsymmetrical butatriene also formed a small amount of another head-to-tail dimer. Although the allene dimer is stable in nonpolar solvents, it converts to other bicyclic and tricyclic compounds in MeOH or CH3CN at room temperature.

Tetraphenyl[5]cumulene (tetraphenylhexapentaene) underwent cyclotrimerization in refluxing toluene for 10–15 min to give a tricyclodecadiene derivative in 68% yield.