Low-dimensional compounds containing cyano groups.: II.: catena-Poly[[2,2′-bipyridine-κ2N:N′)(dicyan-amido-κN)copper(II)]-μ-dicyanamido-κ2N:N′]

The crystal structure of the title compound, [Cu(C2N3)2(C10H8 N2)]n, is formed by neutral zigzag chains of the [-NC-N-CN-Cu((bpy)N(CN)2)-NC-N-CN-] type running along the c axis (bpy is 2,2′-bipyridine). The Cu atoms in the chains are pentacoordinated in the form of a distorted tetragonal pyramid, with a CuN5 chromophore. The coordination sites are occupied by two N atoms of one bpy molecule in the basal plane [Cu-N 2.018 (4) and 2.025 (2) Å] and by three terminal N atoms of two dicyanamide ligands. One of the dicyanamide ligands is coordinated in a monodentate fashion through a nitrile N atom in the basal plane [Cu-N 1.963 (4) Å]. The second acts as an end-to-end bridging ligand to a neighbouring Cu atom and is coordinated by one nitrile N atom in the basal plane [Cu-N 2.001 (2) Å], while the second nitrile N atom occupies the apical position [Cu-N 2.159 (2) Å] and originates from the bridge connecting another Cu atom. The shortest intrachain Cu⋯Cu distance is 8.212 (1) Å, as a consequence of the large bridging ligand, whereas the minimum interchain distance between Cu atoms is only 5.77 (7) Å, because of the interdigitation of the chains.