Adiponitrile, C6H8N2, is a key intermediate in the synthesis of the polyamide Nylon 66 and is produced industrially on a large scale. We have determined the crystal and molecular structure of adiponitrile by single-crystal X-ray analysis at 100 K, a suitable crystal (m.p. 275 K) having been grown from the melt at low temperature. The compound crystallizes in the monoclinic space group P21/c with Z = 2. In the crystal structure, the molecule adopts an exact Ci-symmetric gauche-anti-gauche conformation of the C-C-C-C skeleton about an inversion centre. The molecules are densely packed, with short intermolecular contacts between the α-H and nitrile N atoms.
Keywords: adiponitrile; crystal structure; hexanedinitrile; in situ cryocrystallography; polyamide Nylon 66; synthetic intermediate.