catena-Poly[cobalt(II)-di-μ-chlorido-κ4 Cl:Cl-μ-1,5-dimethyl-1H-tetra­zole-κ2 N 3:N 4]: an X-ray powder investigation

The asymmetric unit of the title compound, [CoCl2(C3H6N4)]n, contains two Co atoms, both lying on inversion centres, two Cl atoms and one 1,5-dimethyl­tetra­zole ligand. The coordination polyhedra of both Co atoms adopt flattened octa­hedral geometry, with two N atoms from two ligands in axial positions and four Cl atoms in equatorial sites. Neighbouring Co atoms are linked together via two bridging Cl atoms and one tetra­zole ring to form polymeric chains running along the a axis

catena-Poly[[bis­[1-(2-hydroxy­ethyl)-1H-tetra­zole-κN 4]copper(II)]-di-μ-chlorido]: a powder study

The crystal structure of the title polymeric complex, [CuCl2(C3H6N4O)2]n, was obtained by the Rietveld refinement from laboratory X-ray powder diffraction data collected at room temperature. The unique CuII ion lies on an inversion center and is in a slightly distorted octa­hedral coordination environment. In the hydroxy­ethyl group, all H atoms, the O atom and its attached C atom are disordered over two positions; the site occupancy factors are ca 0.6 and 0.4. The OH group is involved in an intra­molecular O—H⋯N hydrogen bond

trans-Dichloridotetrakis­[1-(2-hydroxy­ethyl)-1H-tetrazole-κN 4]cobalt(II)

The title cobalt(II) complex, [CoCl2(C3H6N4O)4], was obtained from metallic cobalt by direct synthesis. There are two Co atoms in the asymmetric unit, each lying on an inversion centre and adopting a distorted octa­hedral coordination. Classical and non-classical hydrogen bonds are responsible for formation of a three-dimensional polymeric network in the crystal

The First Characterized Coordination Compounds of Macrocyclic Ligands Including Incorporated Tetrazole Rings

The macrocyclic binuclear tetrazole, 2,2,5,5-tetramethyl-12-oxa-1,6,7,8,16,17,18,19-octaazatricyclo­[13.2.1.16,9]­nonadeca-7,9(19),15(18),16-tetraene (<b>L</b>), reacts with copper­(II) chloride or copper­(II) tetrafluoroborate hexahydrate to give complexes [Cu₃Cl₆L₂] (<b>1</b>) or [CuL₂(H₂O)₂]­(BF₄)₂(H₂O) (<b>2</b>), respectively. According to single crystal X-ray analysis, both complexes were found to be coordination polymers. In the crystal structure of complex <b>1</b>, there are neutral linear bibridged trinuclear units Cu₃Cl₆, in which the copper atoms are linked together by double chlorine bridges. Neighboring Cu₃Cl₆ units are bonded to each other by two bridging macrocyclic ligands L due to coordination bonds Cu–N between terminal copper atoms of Cu₃Cl₆ units and the tetrazole ring nitrogen atoms of ligands L to form polymeric chains. In complex <b>2</b>, the copper atom is bonded to three ligands L via the tetrazole ring nitrogen atoms, and to two water molecules, with formation of a square-pyramidal coordination of the metal. In this complex, one of two independent ligands L shows monodentate coordination, whereas another ligand plays the role of a bridge between two neighboring copper atoms being responsible for formation of polymeric cationic chains [CuL₂(H₂O)₂]_<i>n</i>^2<i>n</i>+. A complex system of hydrogen bonds connects the chains and the anions BF₄^– into a three-dimensional network. The temperature-dependent magnetic susceptibility measurements of complex <b>1</b> revealed that the copper­(II) ions were ferromagnetically coupled showing a coupling constant <i>J</i> of 50 cm^–1