The structure-directing influence of α,ω-alkanediammonium ions on the formation of cyanocuprates(I)

The alkane-1,n-diammonium-hexacyanotetracuprates(I) (n = 2 - 4) [NH3(CH2)(2)NH3](infinity)(2)[Cu-4(CN)(6)].2H(2)O (1), [NH3(CH2)(3)NH3](infinity)(2)[Cu-4(CN)(6)].H2O (2) and [NH3(CH2)(4)NH3](infinity)(2)[Cu-4(CN)(6)].2H(2)O (3) and the pentane-1,5-diammonium-tetradecacyanooctacuprate(I) [NH3(CH2)(5)NH3](3infinity)(3)[Cu-8(CN)(14)].3H(2)O (4) were obtained by hydrothermal reaction of ethane-1,2-diamine, propane-1,3-diamine, butane-1,4-diamine and pentane-1,5-diamine with CuCN, NaCN and formic acid. In the crystal structures of compounds 1 - 3 anionic layers of connected (CuCN)(6)-rings which vary in conformation are piled up containing rigid all-anti alpha,omega-alkanediammonium ions as spacers. The dications and water molecules are linked to chains by hydrogen bridges, penetrating the anionic layers in a needle-like fashion. In contrast the deformable dications [NH3(CH2)(5)NH3](2+) in 4 are integrated in cavities of a three-dimensional cyanocuprate(I). Crystal structure data: 1, monoclinic, P2(1)/c, a = 6.982(3) Angstrom, b = 8.579(4) Angstrom, c = 13.054(6) Angstrom, beta = 92.806(10)degrees, V = 780.9(6) Angstrom(3), Z = 2, d(c) = 2.145 gcm(-1), R-1 = 0.094; 2, orthorhombic, C222(1), a = 8.715(2) Angstrom, b = 14.764(3) Angstrom, c = 12.411(2) Angstrom, V = 1596.7(5) Angstrom(3), Z = 4, d(c) = 2.098 gcm(-1), R-1 = 0.026; 3, orthorhombic, Pnn2, a = 7.276(2), Angstrom, b = 8.612(2) Angstrom, c = 14.731(3) Angstrom, V = 923.1(3) Angstrom(3), Z = 2, d(c) = 1.916 gcm(-1), R-1 = 0.036; 4, triclinic, P1, a = 8.113(5) Angstrom, b = 11.068(5) Angstrom, c = 13.689(5) Angstrom, a = 91.270(5)degrees, beta = 99.718(5)degrees, gamma = 103.994(5)degrees, V = 1173.1(10) Angstrom(3), Z = 1, d(c) = 1.746 gcm(-1), R-1 = 0.057.