Crystal structure of a mixed-ligand dinuclear Ba-Zn complex with 2-meth-oxy-ethanol having tri-phenyl-acetate and chloride bridges.

The dinuclear barium-zinc complex, µ-chlorido-1:2κ(2) Cl:Cl-chlorido-2κCl-bis-(2-meth-oxy-ethanol-1κO)bis-(2-meth-oxy-ethanol-1κ(2) O,O')bis-(µ-tri-phenyl-acetato-1:2κ(2) O:O')bariumzinc, [BaZn(C20H15O2)2Cl2(C3H8O2)4], has been synthesized by the reaction of barium tri-phenyl-acetate, anhydrous zinc chloride and 2-meth-oxy-ethanol in the presence of toluene. The barium and zinc metal cations in the dinuclear complex are linked via one chloride anion and carboxyl-ate O atoms of the tri-phenyl-acetate ligands, giving a Ba⋯Zn separation of 3.9335 (11) Å. The irregular nine-coordinate BaO8Cl coordination centres comprise eight O-atom donors, six of them from 2-meth-oxy-ethanol ligands (four from two bidentate O,O'-chelate inter-actions and two from monodentate inter-actions), two from bridging tri-phenyl-acetate ligands and one from a bridging Cl donor. The distorted tetra-hedral coordination sphere of zinc comprises two O-atom donors from the tri-phenyl-acetate ligands and two Cl donors (one bridging and one terminal). In the crystal, O-H⋯Cl, O-H⋯O and C-H⋯Cl inter-molecular inter-actions form a layered structure, lying parallel to (001).

Supramolecular stores of acetic acid--an alternative for metal-organic frameworks.

A series of new complexes: [M(quin-2-c)(2)(H(2)O)(2)]x 4CH(3)COOH (M=Mn(2+), Co(2+) or Ni(2+), quin-2-c is quinoline-2-carboxylate ion) have been synthesized and characterized by X-ray single crystal study. The crystals of the complexes reveal very interesting 1D structures comprising acetic acid molecules. The processes of re- and desolvation of acetic acid by the manganese complex in mild conditions have been studied. The de- and resolvated materials were characterized by elemental analysis, IR spectroscopy and XRD study. The results show that binding of acetic acid is reversible and stoichiometric.

trans-Bis(methanol-κO)bis-(quinoline-2-carboxyl-ato-κN,O)manganese(II).

The title compound, [Mn(C(10)H(6)NO(2))(2)(CH(4)O)(2)], was obtained unintentionally as the product of an attempt to synthesize a polynuclear carboxyl-ate bridged manganese(III/IV) complex, using methanol to reduce the permanganate ion. The mol-ecule is centrosymmetric; the pairs of equivalent ligands coordinate trans to each other in a distorted octa-hedral geometry. Intra-molecular C-H⋯O bonds lying in the equatorial plane stabilize the mol-ecule. In the crystal, mol-ecules are linked by O-H⋯O and C-H⋯O hydrogen bonds, creating a three-dimensional supra-molecular structure. π-π and C-H⋯π inter-actions are also observed. The dihedral angle and centroid-to-centroid distance between the pyridine ring (A) and the benzene ring (B(i)) of a symmetrically related mol-ecule [symmetry code: (i) -1 - x, -y, -z] are 1.27 (11)° and 3.974 (2) Å, respectively. For the C-H⋯π inter-actions, the relevant distances and angles are: C⋯Cg[A(ii)] = 3.643 (2) Å, H⋯Cg[A(ii)] = 2.750 (2) Šand C-H⋯Cg[A(ii)] = 155 (1)° [symmetry code: (ii) x, -1 + y, z].

Structural, spectroscopic, and magnetic study of bis(9,10-dihydro-9-oxo-10-acridineacetate)bis(imidazole)bis(methanol) nickel(II).

The mixed ligand complex [Ni(CMA)2(im)2(MeOH)2] (where CMA = 9,10-dihydro-9-oxo-10-acridineacetate ion, im = imidazole) was prepared, and its crystal and molecular structure were determined. The nickel ions are hexa-coordinated by four oxygen atoms of the carboxylate and hydroxyl groups and by two imidazole nitrogen atoms, to form a distorted octahedral arrangement. The structure consists of a one-dimensional network of the complex molecules connected by strong intermolecular hydrogen bonds. The weak intermolecular C-H...X hydrogen bonds and stacking interactions make up the 2-D structure. Very strong intramolecular hydrogen bonds significantly affect the geometry and vibrational characteristics of the carboxylate group. The UV-vis-NIR electronic spectrum was deconvoluted into Gaussian components. Electronic bands of the Ni(II) ion were assigned to suitable spin-allowed transitions in the D4h symmetry environment. The single ion zero-field splitting (ZFS) parameters for the S = 1 state of Ni(II), as well as the g components, have been determined by high-field and high-frequency EPR (HF-HFEPR) spectroscopy over the frequency range of 52-432 GHz and with the magnetic fields up to 14.5 T: D = 5.77(1) cm-1, E = 1.636(2) cm-1, gx = 2.29(1), gy = 2.18(1), and gz = 2.13(1). These values allowed us to simulate the powder magnetic susceptibility and field-dependent magnetization of the complex.

Adenine ribbon with Watson-crick and Hoogsteen motifs as the "double-sided adhesive tape" in the supramolecular structure of adenine and metal carboxylate.

The cocrystals of adenine and metal (II) quinoline-2-carboxylates (M = Mn2+, Fe2+, Co2+) have been obtained by self-assembly. The complexes are composed of adenine ribbons with the AA22 pairing pattern involving both Watson-Crick and Hoogsteen faces in hydrogen bonding and the neutral molecules of carboxylate positioned in inorganic layers. The very compact supramolecular structure is made by the extensive system of hydrogen bonds and face-to-face pi-pi interactions.