Poly[[tetraaquabis(μ₂-2-nitroterephthalato-κ³O¹:O⁴,O^4′)(μ₂-piperazine-κ³N:N′)dicadmium(II)] dihydrate]

Abstract

In the title complex, {[Cd(2)(C(8)H(3)NO(6))(2)(C(4)H(10)N(2))(H(2)O)(4)] x 2 H(2)O}(n), the Cd(II) atoms show distorted octahedral coordination. The two carboxylate groups of the dianionic 2-nitroterephthalate ligand adopt monodentate and 1,2-bridging modes. The piperazine molecule is in a chair conformation and lies on a crystallographic inversion centre. The Cd(II) atoms are connected via three O atoms from two carboxylate groups and two N atoms from piperazine molecules to form a two-dimensional macro-ring layer structure. These layers are further aggregated to form a three-dimensional structure via rich intra- and interlayer hydrogen-bonding networks. This study illustrates that, by using the labile Cd(II) salt and a combination of 2-nitroterephthalate and piperazine as ligands, it is possible to generate interesting metal-organic frameworks with rich intra- and interlayer O-H...O hydrogen-bonding networks.