RESUMO
Zinc(II) carboxylates with O-, S- and N-donor ligands are interesting for their structural features, as well as for their antibacterial and antifungal activities. The one-dimensional zinc(II) coordination complex catena-poly[[bis(2,4-dichlorobenzoato-κO)zinc(II)]-µ-isonicotinamide-κ(2)N(1):O], [Zn(C7H3Cl2O2)2(C6H6N2O)]n, has been prepared and characterized by IR spectroscopy, single-crystal X-ray analysis and thermal analysis. The tetrahedral ZnO3N coordination about the Zn(II) cation is built up by the N atom of the pyridine ring, an O atom of the carbonyl group of the isonicotinamide ligand and two O atoms of two dichlorobenzoate ligands. Isonicotinamide serves as a bridge between tetrahedra, with a Zn···Zn distance of 8.8161â (7)â Å. Additionally, π-π interactions between the planar benzene rings contribute to the stabilization of the extended structure. The structure is also stabilized by intermolecular hydrogen bonds between the amino and carboxylate groups of the ligands, forming a two-dimensional network. During thermal decomposition of the complex, isonicotinamide, dichlorobenzene and carbon dioxide were evolved. The final solid product of the thermal decomposition heated up to 1173â K was metallic zinc.
Assuntos
Complexos de Coordenação/química , Zinco/química , Cristalografia por Raios X , Ligação de Hidrogênio , Ligantes , Estrutura Molecular , Condutividade TérmicaRESUMO
A novel tetranuclear manganese(II/III) complex with anions of pyridine-2,6-dicarboxylic acid (dipicolinic acid) has been synthesised and magneto-structurally characterised. The crystal structure of [Mn(II)2Mn(III)2(dipic)6(H2O)4]·2CH3OH·4H2O has been determined by single-crystal X-ray diffraction. The tetranuclear complex molecule [Mn(II)2Mn(III)2(dipic)6(H2O)4] is centrosymmetric and two manganese(II) and two manganese(III) atoms are bridged by four dipicolinate ligands. The complex molecules and uncoordinated water and methanol molecules are connected through hydrogen bonds and they form a 3D supramolecular hydrogen-bonding network.
Assuntos
Manganês/química , Compostos Organometálicos/química , Ácidos Picolínicos/química , Campos Magnéticos , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese químicaRESUMO
The asymmetric unit of the title compound, [Co(C(8)H(6)NO(2))(2)(H(2)O)(4)], contains one half-mol-ecule. The Co(II) atom lies on an inversion centre and is coordinated by two N atoms of the pyridine rings of 3-(3-pyrid-yl)acrylate anions and four O atoms of water mol-ecules in a distorted octa-hedral coordination geometry. In the crystal structure, inter-molecular O-Hâ¯O hydrogen bonds link the mol-ecules, forming a three-dimensional network.
RESUMO
In the crystal structure of the title compound, [Cd(C(15)H(14)NO(2))(2)(C(6)H(7)NO)(2)](n), the Cd atom displays a distorted octa-hedral geometry, including two pyridine N atoms and two hydroxyl O from four symmetry-related 3-pyridylmethanol (3-pyme) ligands and two carboxylate O atoms from mefenamate [2-(2,3-dimethyl-anilino)benzoate] anions. The Cd atoms are connected via the bridging 3-pyme ligands into chains, that extend in the a-axis direction. The Cd atom is located on a center of inversion, whereas the 3-pyme ligands and the mefenamate anions occupy general positions.
RESUMO
The dinuclear mol-ecule of the title compound, [Cd(2)(C(6)H(4)NO(2))(4)(C(2)H(8)N(2))(2)(H(2)O)(2)]·2H(2)O, lies on an inversion centre and forms 12-membered (CdNC(3)O)(2) metallacycles with the two Cd(2+) ions bridged by two nicotinate ligands. Both Cd(2+) ions display coordination polyhedra with a distorted octa-hedral geometry that includes two pyridine N atoms from bridging and terminal nicotinate anions, two amine N atoms from chelating ethylene-diamine ligands, carboxylate O atoms from bridging nicotinate anions and water O atoms. Inter-molecular O-Hâ¯O and N-Hâ¯O hydrogen bonds result in the formation of a three-dimensional network, and π-π stacking inter-actions are observed between symmetry-related pyridine rings of bridging as well as terminal nicotinate anions (the centroid-centroid distances are 3.59 and 3.69â Å, respectively, and the distances between parallel planes of the stacked pyridine rings are 3.53 and 3.43â Å, respectively). The two methylene groups of the ethylene-diamine ligand are disordered over two positions; the site occupancy factors are ca 0.8 and 0.2.
RESUMO
The crystal structure of the title compound, [Co(C(7)H(6)NO(2)S)(2)(H(2)O)(4)], is a polymorph of the structure first reported by Du, Zhao & Wang [(2004). Dalton Trans, pp. 2065-2072]. The asymmetric unit of the title compound contains one half-mol-ecule; the Co(II) atom lies on an inversion centre in a distorted octa-hedral geometry coordinated by two N atoms of the pyridine rings of the 4-pyridylthio-acetate anions and four O atoms of water mol-ecules. In the crystal structure, inter-molecular O-Hâ¯O hydrogen bonds link the mol-ecules, forming a three-dimensional network.
RESUMO
The title compound, [Cu(3)(C(3)H(5)O(2))(6)(C(6)H(7)NO)(4)](n), is composed of polymeric chains formed by alternating centrosymmetric Cu(2)(mu-CH(3)CH(2)CO(2))(4) and Cu(C(3)H(5)O(2))(2)(C(6)H(7)NO)(2) units. These elemental units are linked by two bridging 3-pyridylmethanol (3PM) ligands. The Cu(2)(mu-CH(3)CH(2)CO(2))(4) group presents a centrosymmetric tetrabridged structure with four syn-syn bridging propionate ligands to which two 3PM molecules are bonded (through N), occupying the apical positions of each square-pyramidal polyhedron around the Cu(II) ions. The remaining mononuclear group is centred around a third Cu(II) ion, which lies on a symmetry centre and is bound to two monodentate propionate groups (through O), two monodentate 3PM molecules (through N) and two bridging 3PM molecules (through O), thus completing a square-bipyramidal CuO(2)N(2)O(2) coordination.
