Structure of 4-dibenzofurancarboxaldehyde, C13H8O2.

Mr = 196.21, monoclinic, P2(1)/n, a = 6.589 (1), b = 9.784 (2), c = 14.394 (2) A, beta = 95.69 (1) degrees, V = 923.4 (3) A3, Z = 4, Dx = 1.41 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.89 cm-1, F(000) = 408, T = 296 K, R = 0.048 for 964 unique reflections having I greater than 3 sigma I. The average C-C bond length within the benzenoid rings in 4-dibenzofurancarboxaldehyde is 1.388 (9) A; the average interior angle is 120.0 (2.6) degrees. While two of the three rings of 4-dibenzofurancarboxaldehyde are planar, the benzenoid ring to which the carbonyl group is attached is slightly non-planar. The dihedral angle between the two benzenoid rings measures 1.4(1) degrees. The structure is composed of pairs of 4-dibenzofurancarboxaldehyde molecules related by inversion centers. This structure is further characterized by approaches of both the carbonyl and the furan O atoms to ring H atoms with separations which are slightly less than the sum of the relevant van der Waals radii.