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The purplish-red rod-like crystal structure of novel bimetallic metal–organic-frameworks (MOF) {CoZn[(4,4′-BDA)(Phen)]2}n has been obtained by the reaction of Co2+, Zn2+ (the molar ratio Co: Zn = 1:1), 1,10-phenanthroline (Phen) and 4, 4′-biphenyldicarboxylic acid (4,4′-H2BDA), in which Zn ions of the previously reported monometallic MOF {[Zn(4,4′-BDA)(Phen)]2·(HCON(CH3)2}n are partly substituted by Co ions. The crystal structure of {CoZn[(4,4′-BDA)(Phen)]2}n has been characterized by IR, X-ray photoelectron spectroscopy (XPS), and single-crystal X-ray diffraction analysis. Then, the precursors CoZn-MOF-B@C were obtained by adding a surfactant, activated carbon, and NaOH. Its derivative ZnO/CoO@C was used as anode material for lithium-ion batteries, which showed good lithium storage performance. The initial discharge specific capacity of ZnO/CoO@C is 1437.9 mAh g−1 at a current density of 0.2 A g−1, and after 100 cycles, the specific capacity drops to 741.8 mAh g−1. [ABSTRACT FROM AUTHOR]

The novel insecticide tetrachlorantraniliprole was synthesized utilizing 2,3,5-trichloropyridine as the starting material by a six-step route in 18% yield. The process of simultaneous oxidation and acyl chlorination was studied by in situ FTIR. The molecular structure of tetrachlorantraniliprole was identified by means of NMR, IR, MS, and X-ray diffraction analyses. The single crystal of tetrachlorantraniliprole was formed from toluene solvent, and exhibited monoclinic P21/n group with crystal parameters of a = 15.3316(16) Å, b = 16.7139(16) Å, c = 19.6687(19) Å, V = 4835.2(8) Å3, and Z = 4. Moreover, its density = 1.605 g/m³, F(000) = 2328.0, μ = 2.17 mm-1, and 26933 reflections were measured (2.992° ≼ 2θ ≼ 51.998°). [ABSTRACT FROM AUTHOR]

Two new heterometallic CuEr cluster complexes based on 3,5-dichlorobenzoic acid (HL) and 2,2′:6′,2″-terpyridine (TPY), [Cu(L)(TPY)][Er(L)4]·H2O (1) and [Cu(L)(TPY)][Er2(L)7] (2), have been hydrothermally prepared by controlling the metal–ligand ratios. Comparative study revealed that metal–ligand ratios affected the coordination modes of L− and thus generate two distinct structures. Both complexes display as ion-pair bicomponent structures. The cationic [Cu(L)(TPY)]+ components show the similar binuclear cluster structure in two complexes, while the two anionic parts are very different. In 1, two Er(III) centers are coordinated by four bridging and four chelating L− ligands to form the binuclear anionic [Er2(L)8]2− cluster. While in 2, all L− ligands show the bridging modes and connect the Er(III) centers into an extended one-dimensional (1D) chain. So the overall structures of 1 and 2 are bicomponent 0D + 0D and 0D + 1D structures, respectively. Direct current magnetic susceptibility measurements were performed for two complexes and they both showed antiferromagnetic behavior. [ABSTRACT FROM AUTHOR]

Single crystals of the polymeric title complex tetraaquadinicotinatostrontium (SPYC) were successfully grown by a simple and efficient method—the gel encapsulation technique. Sodium metasilicate was used as the gel medium for this purpose. The crystal structure of the complex indicates that it belongs to triclinic system with space group P1¯. The packing diagram of the complex shows uniformly arranged 'χ'-shaped hydrophobic channels. The thermal decomposition of the crystals have been studied by thermogravimetric analysis at four different heating rates and kinetic parameters including apparent activation energy (Ea), and pre-exponential factor (log A) were calculated by Kissinger, Ozawa and Flynn-Wall-Ozawa methods. Analytical techniques including FT-IR, CHN, powder and single-crystal X-ray diffraction were also carried out to characterize the grown crystals. The solid-state luminescent properties of free ligand and complex were also investigated at room temperature. [ABSTRACT FROM AUTHOR]

In this work, a series of new metal phosphonates were hydrothermally synthesized and structurally characterized based on m-xylylenediphosphonic acids (HL), including [M(HL)(bpy)] (M = Mn 1, Co 2), [MHL)(phen)] (M = Co 3, Cu 4), and [Cu(HL)(bpy″)] 5 (bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, bpy″ = 4,4′-dimethyl-2,2′-bipyridine). X-ray diffraction indicated that compounds 1 and 2 were isomorphic. Complexes 3 and 4 were shown to crystallize in different space groups but had similar crystallographic units. In the complexes, HL was seen to partially deprotonate to afford HL. The HL ligands in 1- 4 functioned as tetradentate ligands with each phosphonate group adopting bidentate coordination mode with two M centers to generate a 2D layer. In addition, the HL anions in 5 functioned as tridentate ligands with one phosphonate group adopting the bidentate mode and another phosphonate group adopti ng the monodentate mode, thus linking three Cu atoms to provide a 1D chain. The IR and thermal stabilities of these compounds were subsequently examined. [ABSTRACT FROM AUTHOR]

[Co2(TTBT)4(1,2-BDC)2] n  · 4nH2O (1), [Pb2(TTBT)2(1,3-BDC)2] n  · nTTBT · 2nH2O (2), [Fe(TTBT)(1,4-BDC)(H2O)] n (3), and [Zn(TTBT)(1,4-BDC)(H2O)] n (4) have been hydrothermally synthesized by self-assembly of TTBT (TTBT = 10,11,12,13-tetrahydro-4,5,9,14-tetraaza-benzo[b]triphenylene), benzene-dicarboxylic acid ligands 1,2-H2BDC, 1,3-H2BDC or 1,4-H2BDC (1,2-H2BDC = 1,2-benzenedicarboxylic acid, 1,3-H2BDC = 1,3-benzenedicarboxylic acid, 1,4-H2BDC = 1,4-benzenedicarboxylic acid), and various metal salts. Compound 1 has dinuclear cluster units, four dimeric Co2 units connected to form a 32-membered ring via weak offset π–π interactions, which are further stacked via strong π–π interactions to form a 3-D supramolecular framework. Complex 2 contains 2-D layers with rhombohedral grids, which are connected to a 3-D structure by π–π interactions. 3 and 4 feature 1-D infinite chains, which are further extended by strong π–π interactions and O–H···O hydrogen bonds resulting in 3-D supramolecular architectures. The photoluminescent properties of 2 and 4 have also been investigated. [ABSTRACT FROM AUTHOR]

Two lanthanide(III) coordination polymers, namely [Ce(pzdc)(HO)] ( 1), [Er(pzdc)(μ-OH)(HO)]· nHO ( 2) (Hpzdc = pyrazine-2,5-dicarboxylic acid), have been hydrothermally synthesized and characterized by single crystal X-ray diffraction and magnetic measurements. Polymer 1 crystallizes in triclinic space group P-1, with a = 6.2875(6), b = 6.7396(6), c = 13.3858(14) Å, α = 82.858(4), β = 83.118(4), γ = 63.452(4)°, V = 502.16(8) Å, and Z = 2. Polymer 2 crystallizes in monoclinic space group P2(1)/ c, with a = 11.706(4), b = 6.151(2), c = 14.063(5) Å, β = 92.255(3), V = 502.16(8) Å, and Z = 4. Single-crystal X-ray diffraction studies show that compound 1 possess a 3D framework structure consisted of double chains. Compound 2 features a 3D open framework structure with a dinuclear Er(III) secondary building unit. Magnetic studies for complex 1 show stronger antiferromagnetic coupling between the Ce(III) ions. Graphical Abstract: Two lanthanide(III) coordination polymers, namely [Ce(pzdc)(HO)] n ( 1), [Er(pzdc)(μ-OH)(HO)] n· nH2O ( 2), have been hydrothermally synthesized and characterized. Compound 1 possess a 3D framework structure consisted of double chains. Compound 2 features a 3D open framework structure with a dinuclear Er(III) secondary building unit. Magnetic studies for complex 1 show stronger antiferromagnetic coupling between the Ce(III) ions.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In the present study we report the synthesis, crystal structure, spectroscopic and thermal analysis of mixed alkali A(NH)(HCO)(HCO)(HO) with A = K, Rb. Single crystal refinements showed that the two compounds Rb(NH)(HCO)(HCO)(HO) and K(NH)(HCO)(HCO)(HO) adopt P − 1 space group. The nine fold coordination cationic sites are randomly occupied by Rb/NH and K/NH respectively for rubidium and potassium compounds. The structure consists of a three-dimensional network formed by the succession along (c) axis of corrugated sheets formed by alkali polyhedra layers in the packing of four-membered rings [A(HCO)(HCO)] linked and bridged by oxalate groups that behave as bi and tetradentate ligand under three different coordination modes. The stability of the crystal lattice is ensured by interesting hydrogen bonding contacts: N-H···O and O-H···O. The thermal behavior under air reveals two anomalies at 368 and 402 K attributed respectively to a structural phase transition probably due to the reorientation of ammonium tetrahedral and to the release of crystalline water. IR spectroscopy further confirms that this material loses crystallization water gradually in the temperature range 400-460 K. Graphical Abstract: Crystal structures of Rb(NH)(HCO)(HCO)(HO) and K(NH)(HCO)(HCO)(HO) adopt isotypic three dimensional frameworks formed by the succession along (c) axis of corrugated sheets. Structure of A(NH)(HCO)(HCO)(HO).[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Synthesis, characterization, crystal structure, and biological studies of two complexes with glycolic acid are described. The solid complexes were formulated as K2[VO(C2H2O3)(C2H3O3)2] · H2O (1) and K2[{VO2(C2H2O3)}2] (2) and characterized by X-ray studies, Fourier transform infrared spectroscopy (FTIR), Electron paramagnetic resonance (EPR), and magnetic susceptibility. Conversion of 1 to 2 was studied in aqueous solution by UV-Vis spectroscopy and in the solid state by diffuse reflectance spectroscopy. Complex 2 contains dinuclear [{VO2(C2H2O3)}2]2- anions in which glycolate(2-) is a five-membered chelating ring formed by carboxylate and α-hydroxy groups. The geometry around the vanadium in 2 was interpreted as intermediate between a trigonal bipyramid and a square pyramid. Vanadium(IV) is pentacoordinate in 1 as a distorted square pyramid. Complex 1 contains a vanadyl group (V=O) surrounded by two oxygens from deprotonated carboxylate and hydroxy groups forming a five-membered ring. Two oxygens from different glycolates(1-) are bonded to the (V=O) also. Biological analysis for potential cytotoxic effects of 1 was performed using Human Cervix Adenocarcinoma (HeLa) cells, a human cervix adenocarcinoma-derived cell line. After incubation for 48 h, 1 causes 90 and 95% of HeLa cells death at 20 and 200 μmol L-1, respectively. [ABSTRACT FROM AUTHOR]