A NEW CRYSTAL-STRUCTURE OF 3,6-DIPHENYLPYRROLO(3,4-C)PYRROLE-1,4-DITHIONE

C18H12N2S2, M(r) = 320.426, monoclinic, C2/c, a = 27.008 (4), b = 6.982 (1), c = 7.935 (1) angstrom, beta = 100.64 (1)-degrees, V = 1470.6 (7) angstrom 3, Z = 4, D(x) = 1.447, D(m) = 1.436 Mg m-3, graphite-monochromatized Cu K-alpha radiation, lambda = 1.5418 angstrom, mu = 3.18 mm-1, T = 293 K, F(000) = 664, R = 0.064 for 1496 reflections. The molecule has C2 symmetry. Both phenyl rings are twisted, in opposite directions, out of the plane of the heterocyclic ring system by 30.1 (2)-degrees. The heterocyclic ring system is not quite planar, as the two five-membered rings form a dihedral angle of 5.4 (1)-degrees. Along the stacking axis, alternate molecules lie directly above each other, forming columns. The molecules in adjacent columns overlap only at the S-C(1), C(1)-N, N-C(3) and N-H bonds in one stack, and the S-C(4), C(4)-N, N-C(6) and N-H bonds in the other. The stacking arrangement can be compared to the bricks in a brick wall.