Hydrothermal reaction of zinc nitrate, 4-(4-carboxyphenoxy)phthalate acid (H3cpop), and different N-donor coligands has afforded six novel supramolecular compounds, in which the nature of the neutral coligands plays a crucial structure-directing role. [Zn(Hcpop)(H2O)3]n (1) and [Zn(Hcpop)(phen)(H2O)]n (2, phen = 1,10-phenanthroline) form three-dimensional (3D) supramolecular frameworks linked by H-bonds and π–π interactions based on discrete molecules. Similarly, [Zn2(Hcpop)2(4,4′-bpy)3(H2O)2]n·4nH2O (3) possesses a 3D supramolecular structure, aggregated by interesting one-dimensional (1D) armed-polyrotaxane chains. [Zn6(cpop)4(4,4′-bpy)2(H2O)2]n (4, 4,4′-bpy = 4,4′-bipyridine) exhibits a complicated 3D framework, which can be rationalized as a (3,6,6)-connected trinodal net with a unique (4.62)2(42.69.83.10)(44.68.83) topology. [Zn3(cpop)2(bpdb)(H2O)2]n (5, bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene) is a 3D structure containing two-dimensional (2D) metal–carboxylate layers motifs, which are furt...

Assembly of Discrete One-, Two-, and Three-Dimensional Zn(II) Complexes Containing Semirigid V-Shaped Tricarboxylate Ligands

Linkage of the trigonal complex [Fe2NiO(Piv)6] (where Piv– = pivalate) by a series of polypyridine ligands, namely, tris(4-pyridyl)triazine (L2), 2,6-bis(3-pyridyl)-4-(4-pyridyl)pyridine (L3), N-(bis-2,2-(4-pyridyloxymethyl)-3-(4-pyridyloxy)propyl))pyridone-4 (L4), and 4-(N,N-diethylamino)phenyl-bis-2,6-(4-pyridyl)pyridine (L5) resulted in the formation of novel coordination polymers [Fe2NiO(Piv)6(L2)]n (2), [Fe2NiO(Piv)6(L3)]n (3), [Fe2NiO(Piv)6(L4)]n·nHPiv (4), and [{Fe2NiO(Piv)6}4{L5}6]n·3nDEF (5, where DEF is N,N-diethylformamide), which were crystallographically characterized. The topological analysis of 3, 4, and 5 disclosed the 3,3,4,4-connected 2D (3, 4) or 3,4,4-connected 1D (5) underlying networks which, upon further simplification, gave rise to the uninodal 3-connected nets with the respective fes (3, 4) or SP 1-periodic net (4,4)(0,2) (5) topologies, driven by the cluster [Fe2Ni(μ3-O)(μ-Piv)6] nodes and the polypyridine μ3-L3,4 or μ2-L5 blocks. The obtained topologies were compared with those ...

Heterometallic Coordination Polymers Assembled from Trigonal Trinuclear Fe2Ni-Pivalate Blocks and Polypyridine Spacers: Topological Diversity, Sorption, and Catalytic Properties

A dysprosium metal–organic framework, {[Dy(μ2-FcDCA)1.5(MeOH)(H2O)]·0.5H2O}n (1), where FcDCA = 1,1′-ferrocene dicarboxylic acid, was prepared by slow-diffusion technique at room temperature. The crystal structure analysis of 1 by single-crystal X-ray diffraction reveals different binding modes of FcDCA linkers coordinated with Dy(III) metal ions, which forms continuous porous two-dimensional (2D) infinite framework. The resulting 2D layers are linked by π···π interactions to build three-dimensional (3D) supramolecular framework. Observably, this thermally stable 3D architecture was topologically simplified as a three-connected uninodal net with fes topology. Furthermore, the practical applicability of 1 was investigated as a fluorescence sensor for the sensitive detection of picric acid in aqueous medium with an impressive detection limit of 0.71 μM with quenching constant (KSV) quantified to be 8.55 × 104 M–1. The distinguished selectivity in the presence of other nitroaromatics suggests the possible in...

Dy(III)-Based Metal-Organic Framework as a Fluorescent Probe for Highly Selective Detection of Picric Acid in Aqueous Medium.

Seven new mixed-ligand complexes based on L [L = 3,6-bis(imidazol-1-yl)pyridazine], namely, [Ni(L)2(SCN)2]n (1), [Cu5(L)(1,2-BDC)4(μ3-OH)2]n (2), {[Cu4(L)2(1,3-HBDC)(1,3-BDC)(μ3-OH)4]·ClO4·2.6H2O}n (3), {[Ni(L)(1,4-BDC)H2O]·0.25H2O}n (4), [Co(L)(1,3,5-H2BTC)2H2O]n (5), {[Cu2(L)(2,6-PYDC)2(H2O)2]·4.4H2O}n (6), and {[Co(L)(4,4′-OBA)]·3.725H2O}n (7) [1,2-benzenedicarboxylic acid (1,2-H2BDC), 1,3-benzenedicarboxylic acid (1,3-H2BDC), 1,4-benzenedicarboxylic acid (1,4-H2BDC), 1,3,5-benzenetricarboxylic acid (1,3,5-H3BTC), 2,6-pyridine dicarboxylic acid (2,6-H2PYDC), and 4,4′-oxydibenzoic acid (4,4′-H2OBA)], have been synthesized by solvothermal reactions. Complexes 1 and 2 possess a two-dimensional (2D) layered structure, and the 2D framework of complex 1 can be rationalized to be a four-connected {44·62} topological sql network, while 2 exhibits a similar topological network with pentanuclear [Cu5(μ3-OH)2(μ2-COO−)6]2+ secondary building units (SBUs). Complex 3 presents an 8-connected sqc3 3D framework based on a chair-shaped [Cu4(μ3-OH)4]4+ SBU with a Schlafli symbol of {424·64}. Complex 4 displays a 3D framework with diamondoid topology, which includes L/Ni(II)/L helical chains. Complex 5 features a 1D chain structure formed by L ligands. Complex 6 shows a dinuclear structure, which is arranged into a 1D supramolecular chain by hydrogen-bonding interactions. The 3D framework of 7 presents a 4-connected porous architecture with a Schlafli symbol of {66}, the same as that of complex 4. The powder X-ray diffraction spectra, IR spectra, UV-vis absorption spectra and thermal stabilities of 1–7 have been investigated. Moreover, in the complex-catalyzed homocoupling reaction of 4-substituted aryl iodides, the catalytic activities of 1–7 have also been studied and discussed.

A series of new mixed-ligand complexes based on 3,6-bis(imidazol-1-yl)pyridazine: syntheses, structures, and catalytic activities

Five new ZnII/CdII coordination polymers constructed from di(1H-imidazol-1-yl)methane (L) mixed with different auxiliary carboxylic acid ligands formulated as [Zn(L)(H2L1111)2·(H2O)0.2]n (1), {[Zn(L)(L222)]·H2O}n (2), {[Cd2(L)2(L222)2]·2H2O}n (3), {[Cd(L)(L33)]·H2O}n (4) and [Cd(L)(L44)]n (5) (H3L1111 = 1,3,5-benzenetricarboxylic acid, H2L222 = 4,4′-oxybis(benzoic acid), H2L33 = m-phthalic acid and H2L44 = p-phthalic acid) have been synthesized under hydrothermal conditions and structurally characterized. Four related auxiliary carboxylic acids were chosen to examine the influences on the construction of these coordination frameworks with distinct dimensionality and connectivity. The coordination arrays of 1–5 vary from 1D zigzag chain for 1, 2D (4,4) layer for 2–4, to 2-fold interpenetrated 3D coordination network with the α-Po topology for 5. The thermal and photoluminescence properties of complexes 1–5 in the solid state have also been investigated.

Zn(II) and Cd(II) coordination polymers assembled by di(1H-imidazol-1-yl)methane and carboxylic acid ligands

A new multifunctional semirigid acylamide ligand comprising a tetrazole ring, N-(1H-tetrazol-5-yl)benzamide (HL), has been synthesized, with which five coordination polymers of different metal ions, namely, CdL2 (1), AgL (2), MnL2 (3), CuL2 (4), PbL2 (5), have been prepared and characterized by elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. The X-ray diffraction analysis reveals that compound 1 crystallized in a chiral space group and is a 3D non-interpenetrated diamondoid framework with Cd(II) centers in tetrahedral geometry. Compound 2 is a 2D coordination polymer with a 3-connected 4·82-fes topology. Compounds 3 and 4 are isomorphous, and both of them exhibit an interesting 2D 44-sql network while compound 5 shows 1D zigzag chains. Thermal stabilities, photoluminescence and NLO properties have also been studied.

Structural variation from 1D to 3D: effect of metal centers on the construction of metal–organic coordination polymers with N-(1H-tetrazol-5-yl)benzamide ligand

The asymmetric unit of the title complex, [CdCl(2)(C(14)H(12)N(4)O(2)S)(2)](n), consists of one Cd(II) ion located on the crystallographic inversion centre, one 4-benzoyl-1-isonicotinoylthiosemicarbazide ligand and one chloride ligand The central Cd(II) ion adopts a distorted octahedral coordination geometry formed by two pyridyl N atoms of two ligands, two S atoms of two other ligands and two chloride ligands The thiosemicarbazide ligands act as bridges, linking the metal ions into a two-dimensional layered structure parallel to the bc plane Intermolecular N-HO hydrogen bonds and C-Hpi interactions exist between adjacent layers

Poly[bis(μ‐4‐benzoyl‐1‐isonicotinoylthiosemicarbazide‐κ2N:S)dichloridocadmium(II)]

Two nickel coordination compounds with m-aminophenol-N,N,O-triacetic acid (H3L), [Ni(L)·(H2O)3]2·Ni(H2O)6·4.3H2O (1), and [Ni(L)·H2O]2·Ni(H2O)6 (2), were obtained under similar reaction conditions but at different synthesis temperature. Single crystal X-ray diffraction analysis reveals that both coordination compounds exhibit discrete dimeric entity structures and contain hexaaquanickel cations acting as counter-ions. Unit cell data for (1): triclinic, space group P-1, a = 7.9977(16), b = 10.475(2), c = 12.952(3) A and α = 107.36(3), β = 99.66(3), γ = 96.15(3)°; and for (2): monoclinic, space group P21/c, a = 13.524(3), b = 8.5703(17), c = 13.820(3) A and β = 95.25(3)°. In (1), O–H⋯O hydrogen bonds link the complex anions into a dimeric unit. But in (2), the dimeric unit is generated from two Ni centers bridged by two ligands. Extensive hydrogen bond interactions exist in both coordination compounds, and connect the complex anions, hexaaquanickel cations and/or water molecules, resulting in three-dimensional supramolecular structures. The compounds also have been characterized by elemental analysis, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), FT-IR and UV–Vis spectra. More coordinated water molecules of metal ion are substituted by N and/or O donors of ligand at higher reaction temperature.

Crystal Structure of Two Nickel Complexes with m -Aminophenol- N , N , O -Triacetic Acid, the Effect of Temperature in the Synthesis

The title complex, [Cd(2)(C(2)H(2)N(3))(OH)(SO(4))](n), is a three-dimensional metal-organic framework consisting of pseudo-cubane-like tetranuclear cadmium clusters, which are formed by four Cd(II) atoms, two sulfate groups and two hydroxide groups. The tetranuclear cadmium clusters are connected into a layered substructure by Cd-O bonds and adjacent layers are linked by triazolate ligands into a three-dimensional network. A photoluminescent study revealed that the complex exhibits a strong emission in the visible region which probably originates from a π-π* transition.

Poly[μ3-hydroxido-μ6-sulfato-μ3-(1,2,4-triazolato-κ3N1:N2:N4)-dicadmium(II)]: a cadmium-triazolate coordination polymer with a pseudo-cubane-like tetranuclear cluster.

Qian Liang

Papers

Structural variation from 1D to 3D: effect of metal centers on the construction of metal–organic coordination polymers with N-(1H-tetrazol-5-yl)benzamide ligand

Poly[bis(μ‐4‐benzoyl‐1‐isonicotinoylthiosemicarbazide‐κ2N:S)dichloridocadmium(II)]

Crystal Structure of Two Nickel Complexes with m -Aminophenol- N , N , O -Triacetic Acid, the Effect of Temperature in the Synthesis

Poly[μ3-hydroxido-μ6-sulfato-μ3-(1,2,4-triazolato-κ3N1:N2:N4)-dicadmium(II)]: a cadmium-triazolate coordination polymer with a pseudo-cubane-like tetranuclear cluster.