Discrete systems and two-dimensional coordination polymers containing potentially multidentate and bridging inorganic anions: Observation of a new type of two-dimensional topology

A novel tetrazolate- and cyanide-bridged three-dimensional heterometallic coordination polymer: crystal structure, thermal stability and magnetic properties

By using environmentally friendly K3[Co(CN)6] as a cyanide source, the solvothermal reaction of CuCl2 and tetrazole (Htta) led to a novel tetrazolate- and cyanide-bridged three-dimensional heterometallic CuII–CoIII complex, namely poly[[hexa-μ2-cyanido-κ12 C:N-pentakis(μ3-tetrazolato-κ3 N 1:N 2:N 4)cobalt(III)tetracopper(II)] monohydrate], {[CoIIICuII 4(CHN4)5(CN)6]·H2O} n , (I). The crystal structure analysis reveals that it is the first example of a (6,8,8)-connected three-dimensional framework with a unique topology, constructed from anionic [Co(CN)6]3− and cationic [(Cu1)2(tta)2]2+ and [(Cu2Cu3)(tta)3]+ units through μ2-cyanide and μ3-tetrazolate linkers. The compound was further characterized by thermal analysis, vibrational spectroscopy (FT–IR), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM–EDS) and magnetic measurements. The magnetic investigation indicates that the complex exhibits antiferromagnetic coupling between adjacent CuII cations.

Synthesis, crystal structure and magnetic properties of a two-dimensional cyanide-based heterometallic coordination polymer with cationic piperazinium ligands: poly[aquatetra-μ2-cyanido-κ(8)C:N-dicyanido-κ(2)C-(piperazinium-κN(4))cobalt(III)copper(II)]

Cyanide as a bridge can be used to construct homo- and heterometallic complexes with intriguing structures and interesting magnetic properties. These ligands can generate diverse structures, including clusters, one-dimensional chains, two-dimensional layers and three-dimensional frameworks. The title cyanide-bridged Cu(II)-Co(III) heterometallic compound, [Cu(II)Co(III)(CN)6(C4H11N2)(H2O)]n, has been synthesized and characterized by single-crystal X-ray diffraction analysis, magnetic measurement, thermal study, vibrational spectroscopy (FT-IR) and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM-EDS). The crystal structure analysis revealed that it has a two-dimensional grid-like structure built up of [Cu(Hpip)(H2O)](3+) cations (Hpip is piperazinium) and [Co(CN)6](3-) anions that are linked through bridging cyanide ligands. The overall three-dimensional supramolecular network is expanded by a combination of interlayer O-H...N and N-H...O hydrogen bonds involving the coordinated water molecules and the N atoms of the nonbridging cyanide groups and monodentate cationic piperazinium ligands. A magnetic investigation shows that antiferromagnetic interactions exist in the title compound.

Crystal structure of a two-dimensional grid-type iron(II) coordination polymer: poly[[di-aqua-tetra-μ-cyanido-diargentate(I)iron(II)] trans-1,2-bis(pyridin-2-yl)ethyl-ene disolvate]

In the title compound, {[Ag2Fe(CN)4(H2O)2]·2C12H10N2} n , the asymmetric unit contains one Fe(II) cation, two water mol-ecules, two di-cyanido-argentate(I) anions and two uncoordinating 1,2-bis-(pyridin-2-yl)ethyl-ene (2,2'-bpe) mol-ecules. Each Fe(II) atom is six-coordinated in a nearly regular octa-hedral geometry by four N atoms from di-cyanido-argentate(I) bridges and two coordinating water mol-ecules. The Fe(II) atoms are bridged by di-cyanido-argentate(I) units to give a two-dimensional layer with square-grid spaces. The inter-grid spaces with inter-layer distance of 6.550 (2) Å are occupied by 2,2'-bpe guest mol-ecules which form O-H⋯N hydrogen bonds to the host layers. This leads to an extended three-dimensional supra-molecular architecture. The structure of the title compound is compared with some related compounds containing di-cyanido-argentate(I) ligands and N-donor organic co-ligands.