An ortho­rhom­bic polymorph of N (1),N (4)-diphenyl-3,6-bis­(phenyl­imino)­cyclo­hexa-1,4-diene-1,4-di­amine

A new ortho­rhom­bic polymorph of the title compound, C(30)H(24)N(4), with a density of 1.315 Mg m(−3), has been obtained. The mol­ecule is centrosymmetric with the centroid of the cyclo­hexa-1,4-diene ring located on an inversion center. The two unique benzene rings are almost perpendicular to each other [dihedral angle = 86.70 (6)°] and are oriented at dihedral angles of 30.79 (5) and 68.07 (5)° with respect to the central cyclo­hexa­diene ring. In the crystal, π–π stacking is observed between the central cyclo­hexa-1,4-diene-1,4-di­amine unit and a phenyl ring of a neighboring mol­ecule [centroid–centroid distance = 3.7043 (7) Å]. The crystal structure of the triclinic polymorph [Ohno et al. (2014 ▶). Acta Cryst. E70, o303–o304] showed chains running along the b-axis direction through weak C—H⋯π inter­actions.