Crystal structure of 5,7,12,14-tetra-hydro-5,14:7,12-bis-([1,2]benzeno)-penta-cene-6,13-dione.

The lattice of 5,7,12,14-tetra-hydro-5,14:7,12-bis-([1,2]benzeno)-penta-cene-6,13-dione, CHO, at 173 K has triclinic (-1) symmetry and crystallizes with four independent half-mol-ecules in the asymmetric unit. Each mol-ecule is generated from a CHO substructure through an inversion center at the centroid of the central quinone ring, generating a wide H-shaped mol-ecule, with a dihedral angle between the mean planes of the terminal benzene rings in each of the two symmetry-related pairs over the four mol-ecules of 68.6 (1) (), 65.5 (4) (), 62.3 (9) (), and 65.8 (8)° (), an average of 65.6 (1)°. This compound has applications in gas-separation membranes constructed from polymers of intrinsic microporosity (PIM). The title compound is a product of a double Diels-Alder reaction between anthracene and -benzo-quinone followed by de-hydrogenation. It has also been characterized by cyclic voltammetry and rotating disc electrode polarography, FT-IR, high resolution mass spectrometry, elemental analysis, and H NMR.