Crystal structure of 5,7,12,14-tetrahydro-5,14:7,12-bis([1,2]benzeno)pentacene-6,13-dione

Abstract

The lattice of 5,7,12,14-tetrahydro-5,14:7,12-bis([1,2]benzeno)pentacene-6,13-dione, C34H20O2, at 173K has triclinic (P-1) symmetry and crystallizes with four independent half-molecules in the asymmetric unit. Each molecule is generated from a C17H10O substructure through an inversion center at the centroid of the central quinone ring, generating a wide H-shaped molecule, with a dihedral angle between the mean planes of the terminal benzene rings in each of the two symmetry-related pairs over the four molecules of 68.6(1) (A), 65.5(4) (B), 62.3(9) (C), and 65.8(8)° (D), 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 p-benzoquinone followed by dehydrogenation. It has also been characterized by cyclic voltammetry and rotating disc electrode polarography, FT-IR, high resolution mass spectrometry, elemental analysis, and 1H NMR.