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Two new isostructural lanthanide(III) coordination polymers based on an unreported zwitterionic ligand, namely, [Ln(ox)(L)]n (ox = oxalate, HL = N,N' -dipropionic acid imidazolium, Ln = Eu or La), are synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, infrared spectroscopy, powder X-ray diffraction, and thermogravimetric analysis. The fluorescence properties of the europium coordination polymer are investigated. In addition, the europium-based coordination polymer is utilized for specific sensing of UO22+ ions, showing high selectivity, a fast response time (8 min) and high sensitivity with noticeable quenching (K sv = 6.19 × 104 M−1) and limit of detection of 1.95 µM. [ABSTRACT FROM AUTHOR]

C23H14IN4O7La, triclinic, P 1 ‾ (no. 2), a = 8.2438(3) Å, b = 12.3786(5) Å, c = 12.6230(5) Å, α = 111.802(1)°, β = 91.144(1)°, γ = 100.6470(10)°, V = 1169.86(8) Å3, Z = 2, Rgt(F) = 0.0313, wRref(F2) = 0.1051, T = 296 K. [ABSTRACT FROM AUTHOR]

Three new metal-organic coordination polymers, namely {[Cu(4,4'-bipy)(5-Hoipa)2](H2O)2}n (I, 5-H2oipa = 5-Hydroxyisophthalicacid, 4,4'-bipy = 4,4'-bipyridine), {[Cu2(4,4'-bipy)(tzb)2](DMF)3} (II, H2tzb = 4-(1H-Tetrazol-5-yl)benzoic acid), and {[Cu(cpdba)(2,2′—bpy)]}n (III, H2cpdba = 4-(4-carboxyphenylamino)-3,5-dinitrobenzoic acid, 2,2'-bipy = 2,2'-bipyridine), have been successfully prepared by using two similar pyridine ligands with different co-ligands under different reaction conditions (slow volatilization for II, solvothermal for I and III). Their structures have been unambiguously determined by both single-crystal X-ray study and elemental analysis. Additionally, the newly synthesized compounds were evaluated to identify the molecular characteristics contributing to their cytotoxicity. They were tested against three human gastric cancer cells (MGC-803, SGC-790 and MKN45) with the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. [ABSTRACT FROM AUTHOR]

C12H21Cl2N3O2, monoclinic, P21/c (no. 14), a = 7.2704(7) Å, b = 11.4750(12) Å, c = 18.7004(19) Å, β = 95.475(2)°, V = 1553.0(3) Å3, Z = 4, Rgt(F) = 0.0372, wRref(F2) = 0.1022, T = 296(2) K. [ABSTRACT FROM AUTHOR]

Reaction of 3-(2-pyridyl)pyrazole-5-carboxylic acid (H 2 L) with Zn(II) or Cu(II) perchlorate yielded [ZnL] n ( 1 ) and [CuL] n ( 2 ) with similar composition. The ligand L 2 − adopts the same μ 3 κ 5 coordination mode. The Zn(II) and Cu(II) atom takes square pyramid coordination polyhedron with some discrepancy. Bigger difference in the dimeric secondary building blocks leads to distinct two-dimensional metal–organic frameworks. The Zn(II) complex fluoresces stronger than the free ligand. The Cu(II) polymer displays strong antiferromagnetic intra-dimer exchange and ferromagnetic inter-dimer exchange. [ABSTRACT FROM AUTHOR]

Four new hexa-nickel(II)-substituted Keggin-type tungstophosphates [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·6HO ( 1, oeen = N-(2-hydroxyethyl)enediamine), [Ni(μ-OH)(oeen)(HO)(B-α-PWO)]·13HO ( 2), [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·3HO ( 3, tran = 1,4,7-triazonane) and [Ni(μ-OH)(oeen)(tran)(HO)(B-α-PWO)]·6HO ( 4) have hydrothermally made by controlling their reaction temperatures. 1- 4 have been characterized by elemental analyses, IR spectra, powder X-ray diffraction, thermogravimetric analyses and single-crystal X-ray diffraction, respectively. Structural analyses reveal that they consist of {Ni(μ-OH)(HO)} cores and B-α-PWO (PW) units, and further are stabilized by organic neutral oeen/tran molecules. 1- 3 are isolated clusters while 4 is the 1D chain structure. It should be noted that the tran molecules in 3 and 4 are derived from the oeen molecules in the starting materials. [ABSTRACT FROM AUTHOR]

Abstract: This paper studied the coordination behavior of azaarylpyrazole carboxylic acids for the first time. Hydrothermal reaction of 5-(pyridine-3-yl)pyrazole-3-carboxylic acid (H2L1) or 5-(pyrazine-2-yl)pyrazole-3-carboxylic acid (H2L2) with CdI2 afforded crystalline {[CdI(HL1)]} n (1) or {[CdI(HL2)(H2O)]·H2O} n (2), respectively. The X-ray diffraction analyses reveal that the different properties of the pyrazolecarboxylate, the iodide, and the cadmium atoms give rise to different crystal structures. The two complexes show covalently bonded two-dimensional metal-organic frameworks with different topology. The two-dimensional layers are further linked to form three-dimensional supramolecular networks through I⋯π halogen bonds or hydrogen bonds. Both complexes show luminescence enhancement compared to the corresponding ligands. [Copyright &y& Elsevier]

C8H8ClNO9, monoclinic, P21/n (no. 14), a = 7.1284(3) Å, b = 8.5538(5) Å, c = 18.7089(10) Å, β = 99.760(2)°, V = 1124.26(10) Å3, Z = 4, Rgt(F) = 0.0381, wRref(F2) = 0.1031, T = 150 K. [ABSTRACT FROM AUTHOR]

Two metal coordination polymers, namely {[Co(MIBA)2]·2H2O}n (SNUT-3) and {[Cu(MIBA)2]·2H2O}n (SNUT-4), where HMIBA = 4-(1H-2-methylimidazol-1-yl)benzoic acid, were prepared by hydrothermal methods. Single-crystal X-ray analysis revealed that the structure of SNUT-3 exhibits a 3D→3D fourfold interpenetrating structure with diamondoid frameworks, while SNUT-4 shows a 2D + 2D → 3D inclined polycatenation structure. The gas adsorption property of SNUT-3 and photocatalytic activity of SNUT-4 for the degradation of Rhodamine B has been explored. [ABSTRACT FROM AUTHOR]

Compound 3-amino-N-[4-chloro-3-(trifluoromethyl)phenyl]-4-morpholino-1H-indazole-1-carboxamide has been synthesised by condensation of 1-chloro-4-isocyanato-2-(trifluoromethyl)benzene with 4-morpholino-1H-indazol-3-amine, which was prepared from 2,6-difluorobenzonitrile by amination with morpholine and then cyclisation with hydrazine hydrate. The crystal structure of the title compound was determined. In addition, the compound possesses a distinct inhibitory capacity against proliferation of the A549 and BGC-823 cancer cell lines. [ABSTRACT FROM AUTHOR]

A new heteroleptic nickel-bis-1,2-dithiolene ion-pair complex, (4-ClBz-1-APy)[Ni(dmit)(mnt)] ( 1 ) (where 4-ClBz-1-APy + = p-chloro-benzyliden-1-aminopyridinium; dmit 2− = 2-thioxo-1, 3-dithiole-4, 5-dithiolate; mnt 2− = maleonitriledithiolate) was synthesized and characterized structurally. The IR spectra, thermal analysis, magnetic and near-IR absorption properties have been investigated for 1 . Complex 1 crystallized in monoclinic system with space group P 2 1 . The anions and cations form the mixed stacked columns separated by the cation columns. The anion stacks are irregular, in which two neighboring heteroleptic [Ni(dmit)(mnt)] − anions are separated by one 4-ClBz-1-APy + cation. The neighboring anions are connected via lateral-to-lateral S…S contacts of dmit 2− ligands and short H…N, H…S and C…S contacts are observed between the cations and the anions. Magnetic susceptibility measurement shows that the magnetic data follows the S = 1 / 2 Heisenberg alternating linear-chain model in the temperature range 40–300 K and Curie-Weiss law below 40 K for 1 . Salts 1 exhibits a intense near-IR absorption in the region of 900–1400 nm, and this near-IR absorption feature makes it to be a promising optical material. [ABSTRACT FROM AUTHOR]

Abstract: Fe(II) and Ni(II) complexes of 4-p-tolyl-2,6-di(2-pyrazinyl)pyridine (tdpzpy) have been synthesized and characterized. The N⋯π interaction involving the uncoordinated pyrazinyl N atom, which is stronger than the corresponding C–H⋯π hydrogen bonding in a similar 4-p-tolyl-2,2′:6′,2″-terpyridine complex, was distinguished as a supramolecular motif. It acts as an edge-to-face force in assembling cations of [Fe(tdpzpy)2]2+ or [Ni(tdpzpy)2]2+ into chains via embrace interlocking. C–H⋯π hydrogen bonds further link the chains into higher dimension net. The electronic absorption and emission properties of [Fe(tdpzpy)2]2+ and [Ni(tdpzpy)2]2+ are largely ligand-centered. [Fe(tdpzpy)2]2+ displays an MLCT absorption at 567nm. The fluorescence of [Ni(tdpzpy)2]2+ is different markedly in methanol and acetonitrile. The ligand-based fluorescence is quenched to some extent by coordination to the d-orbital unfulfilled Fe(II) or Ni(II) atom. [Copyright &y& Elsevier]

C8H7NO4, orthorhombic, Pccn (no. 56), a = 14.1361(10) Å, b = 15.8923(12) Å, c = 6.6410(6) Å, V = 1491.9(2) Å3, Z = 8, Rgt(F) = 0.0406, wRref(F2) = 0.1155, T = 150(2) K. [ABSTRACT FROM AUTHOR]

Although the four complexes were constructed by the same 4-(1 H -2-methyli midazol-1-yl)benzoic acid ligand, their structures are quite different. They exhibit fascinating 0D, 1D, 2D+2D→ 3D, and 3D → 3D structures, respectively. • Four new metal(II) ions complexes were synthesized. • X-ray crystal structure determination. • The fluorescent properties and molecular simulation of the complex 4 was investigated. By modulating the synthetic strategy based on changing metal salt used in the synthesis, four new metal(II) complexes, [Cu(MIBA) 2 (H 2 O) 3 ]·2H 2 O (C 22 H 28 CuN 4 O 9) (1), [Ni 2 (MIBA) 4 (H 2 O) 6 ] n (C 44 H 48 Ni 2 N 8 O 14) (2), [Co(MIBA) 2 ] n (C 22 H 18 CoN 4 O 4) (3) and [Zn(MIBA) 2 ] n (C 22 H 18 ZnN 4 O 4) (4) constructed by 4-(1H-2-methylimidazol-1-yl)benzoic acid (HMIBA) were synthesized under hydrothermal/solvothermal conditions and characterized by single crystal X-ray diffraction, powder XRD, FT-IR, TGA and elemental analysis techniques. Although the four complexes were constructed by the same semi-rigid imidazolium carboxylate ligand, their structures are quite different. The structural analyses revealed that complex 1 is a discrete mononuclear unit, which are extended to form 3 D supramolecular architectures by hydrogen bonds. Complex 2 features a 1D antenna-like chain, complex 3 exhibit a 2D + 2D → 3D structure, and complex 4 exhibits a 3D → 3D fourfold interpenetrating framework. Furthermore, the fluorescent properties and molecular simulation of the complex 4 was also investigated in the solid state at room temperature. [ABSTRACT FROM AUTHOR]