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Reaction of isonicotinic acid N-oxide (HINO) with AgClO4or AgBF4under similar conditions unexpectedly generates two distinct crystalline products {[Ag3(INO)2(HINO)2]·(ClO4)}n(1) and {[Ag(INO)]·(H2O)}n(2). Complex 1consists of a 3-D cationic net with mixed-connected topology and the included perchlorate counterions, whereas 2has a 3-D neutral open framework (4-connected crbtopology) with the accommodation of lattice water. The anion exchange/competition and guest desorption/adsorption behavior have also been thoroughly explored. [ABSTRACT FROM AUTHOR]

This work presents a series of coordination polymers with a dipyridyl-type building block bis[3,5-dimethyl-4-(4′-pyridyl)pyrazol-1-yl]methane (pypz) and different anionic co-ligands. The elongated and flexible backbone of the pypz ligand facilitates the formation of diverse entangled coordination networks, which are well regulated by the auxiliary anionic components. Generally, the anions of nitrate, chloride, and pseudohalide (such as dicyanamide, thiocyanate, and azide) display a monodentate binding mode in this system and serve as terminal pendants of the metal–pypz coordination layers. As a result, 2D → 3D polythreading architectures are mostly observed, except in the case of small chloride anion that leads to twofold parallel interpenetration of the layers. On the other hand, the aromatic dicarboxylates such as terephthalate and biphenyl-4,4′-dicarboxylate behave as rod-like linkers for the construction of diversiform 2D or 3D interpenetrated coordination networks with the aid of pypz. Besides, these crystalline materials may also be significantly affected by other assembled elements such as metal ion, solvent, and metal-to-ligand ratio. [ABSTRACT FROM AUTHOR]

A series of nine mixed-ligand metal-organic frameworks (MOFs) have been prepared by the combination of a bent dipyridyl linker 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole (bpt) and three benzenedicarboxylate isomers (pa = phthalate, ip = isophthalate, and tp = terephthalate), respectively, with different metal ions such as CoII, NiII, CuII, ZnII, and CoII. The framework structures of these neutral polymeric complexes have been determined by the X-ray single- crystal diffraction technique. Structural analysis reveals that the benzenedicarboxylate isomers display versatile coordination modes to manage the metal ions to form 1-D chain or ribbon arrays, which are further extended via the exo-bidentate bpt connectors to give rise to a variety of coordination networks, such as a simple (4,4) layer, 2-D double layer with decorated (4,4) topology, 2-D layer with decorated (3,6) topology, 2-D bilayer with 8².10 topology (2-fold interpenetration), 3-D polythreaded architecture (1-D + 2-D), and 2-fold interpenetrating porous lattice of (4,4) layers. The accessorial secondary interactions such as hydrogen bonding and/or aromatic stacking are also helpful for the extension and stabilization of the final supramolecular aggregates. This work evidently indicates that the isomeric effect of the anionic benzenedicarboxylate is significant in the construction of these network structures, which are also well regulated by the metal centers. The ZnII and CdII MOFs exhibit strong solid-state luminescence emissions at room temperature, which originate differently from intraligand transition or ligand-to-metal charge transfer. Thermal stability of these crystalline materials has been explored by thermogravimetric analysis of mass loss. The 3-D host frameworks of MOFs 8 and 9 show similar porous cavities, and their desorption/ adsorption behaviors of guest solvents have also been investigated. [ABSTRACT FROM AUTHOR]

Four novel ZnII and CdII metal-organic coordination polymers with a versatile building block 5-(4-pyridyl)-1,3,4-oxadiazole-2-thiol (Hpyt) have been prepared under different conditions. (Zn3(pyt)4(OH)2]n (1) and [Cd(pyt)(HCOO)]n (3) were obtained through a solvothermal method, whereas {[Zn(pyt)2(H2O)2]•(DMF)2}n (2) and {[Cd(pyt)2]CHCl3}n (4) were isolated under general conditions. X-ray single-crystal diffraction indicates that the anionic ligand pyt adopts a thioamide isomer in 1, 2, and 4, but a thiolate form in 3. Four types of binding modes involving monodentate (η-Noxa), bidentate (μ-Npy,Noxa, or μ-NpyS,S) and tridentate (μ-Npy,Noxa,S) are observed. The discrepancy of the synthetic routes and metal-coordination preferences facilitates the production of the final crystalline materials with distinct network structures, including a 1D zigzag array of 1 with dangling arms, a common 2D (4,4) coordination layer of 2, a decorated 3D α-Po network of 3, and an unprecedented (3,6)-connected 3D framework of 4 with a (4².6)2(4².6².87.10²) topology. Notably, the hydrolysis of DMF solvates leads to the formation of formate ions, being a component in the structure of 3. Complexes 2 and 4 show 1D channels in which the solvates are accommodated, and even after the exclusion of these guests, the porous host frameworks are still retained. Thermal stability and gas adsorption properties have also been studied. [ABSTRACT FROM AUTHOR]

The reaction of copper(II) nitrate, oxamide, and an angular bridging ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) under hydrothermal conditions affords a 3D pillared-layer coordination framework {[Cu2(4-bpo)(ox)2](H2O)4}n (1) (ox = oxalate), featuring the unique zeolite-type NiP2 network and interesting properties. [ABSTRACT FROM AUTHOR]

Abstract: Self-penetrating coordination networks have recently been demonstrated as an important family of coordination polymers with new topologies and properties. However, the design and control of self-penetrating systems is still an enthralling challenge. In this review, we present the topological types of self-penetrating coordination networks, mainly with single-connectivity, and summarize their designing and constructing strategy. [Copyright &y& Elsevier]

The title coordination polymer, poly­[[tetrakis( N, N′-di­methyl­form­amide)­pentacopper(I,II)]-tetra-μ2-cyano-di-μ3-cyano], [Cu5(CN)6(C3H7NO)4] n, whose structure [Peng & Liaw (1986). Inorg. Chim. Acta, 113, L11–L12] has been redetermined using CCD data, contains four crystallographically independent copper centres, including three CuI ions with tetrahedral or linear geometries and one CuII ion in an octahedral environment. These copper centres are connected by bidentate and tridentate cyanide bridges to form a unique self-penetrating network with 446108 topology, which has been analyzed in detail. Three of the Cu atoms have site symmetries of , 2 and 2. [ABSTRACT FROM AUTHOR]

In the centrosymmetric dinuclear title complex, [Cu2(CH3O)2(C4H8N3O2)2], the two CuII ions are linked by a pair of methoxide bridges, with a non-bonding Cu⋯Cu distance of 3.048 (1) Å. Each CuII center adopts a CuO2N2 square-planar geometry, coordinated by the bidentate bis­(methoxy­carbimido)aminate and two methoxide ligands. [ABSTRACT FROM AUTHOR]

The spontaneous self-assembly reactions of 2,3,5,6-tetrafluorobenzenedicarboxylic acid (H2BDC-F4) with Ca(NO3)2·4H2O in different solvents resulted in the generation of hydrophilic 3D chiral and achiral Ca(II)-organic frameworks {[Ca4(BDC-F4)4(H2O)4]·4H2O}n (1) and [Ca(BDC-F4)(MeOH)2]n (2), respectively. Complex 1 exhibits higher water solubility compared to 2, and further dissolution of 1 in water results in a new achiral crystal, [Ca(BDC-F4)(H2O)4]n (3). All complexes have been characterized by elemental analysis, IR spectroscopy, and single-crystal and powder X-ray diffraction techniques. Complex 1 crystallizes in the tetragonal P41212 chiral space group and features a rare binodal 5-connected network, directed by a unique 3D chiral (10,3)-a water aggregation consisting of two distinct helical arrays. Complex 2 crystallizes in the space group C2/c and has a binodal 4-connected pts net. Complex 3 crystallizes in the space group P21/m and presents a 2D layer framework containing the unprecedented polymeric [CaII-H2O]n chain based on triple μ2-O aqua bridges. The structural discrepancies illustrate the solvent-induced effect on the construction and structural transformation of chiral and achiral coordination frameworks. Moreover, gas (N2 and CO2) adsorption studies show that the dehydrated framework 1a exhibits excellent selective CO2 gas uptake at 195 K. [ABSTRACT FROM AUTHOR]

A series of CdII, CoII, NiII, and PbIImixed-ligand coordination complexes 1−8based on 5-sulfoisophthalic acid (H3sip) and the bent dipyridyl ligand 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) or its 4-pyridyl N-donor analogue (4-bpo) have been synthesized and fully characterized by IR spectra, microanalyses, and single crystal and powder X-ray diffraction techniques. The significant pH effect on assembly of the CdIIcomplexes 1−4has been demonstrated, which leads to the formation of distinct crystalline products, whereas the CoII, NiII, and PbIIsystems 5−8are independent to pH condition of the synthetic reaction. Complexes 1−8display various coordination motifs with different existing forms, conformations, and coordination modes of the organic ligands. Further, extended supramolecular networks are constructed via secondary interactions such as hydrogen-bonding and aromatic stacking. Solid-state properties of thermal stability and fluorescence for these crystalline materials are also presented. [ABSTRACT FROM AUTHOR]

A unique self-penetrating coordination framework with (424.64) network topology is constructed from cage-shaped [Pb6(μ4-O)2(O2C)8] clusters as eight-connected nodes and long V-shaped dicarboxylate backbones as spacers, which interestingly can be regarded as the cross-linking of two interpenetrating six-connected pcunetworks. [ABSTRACT FROM AUTHOR]

The title complex, [CdCl(NCS)(C10H8N2)] n, represents an unusual CdII coordination polymer constructed by two types of anionic bridges and 2,2′-bipyridyl (bipy) terminal ligands. These two types of bridges are arranged around inversion centers. The distorted octahedral coordination of the CdII center is provided by two chloride ions, one N- and one S-donor atom from two thiocyanate ions, and a pair of N atoms from the chelating bipy ligand. Interestingly, adjacent CdII ions are interconnected alternately by paired chloride [Cd...Cd = 3.916 (1) Å] and thiocyanate bridges [Cd...Cd = 5.936 (1) Å] to generate an infinite one-dimensional coordination chain. Furthermore, weak interchain C—H...S interactions between the bipy components and thiocyanate ions lead to the formation of a layered supramolecular structure. [ABSTRACT FROM AUTHOR]

Two related CoII5-aminoisophthalate coordination frameworks [Co5(μ3−OH)2(5-NH2-bdc)4(H2O)2]·7.5H2O (1, 5-NH2-bdc = 5-aminoisophthalate) and [Co5(μ3−OH)2(5-NH2-bdc)4(bpy)0.5(H2O)]·3H2O (2, bpy = 4,4′-bipyridine) based on [Co5(μ3−OH)2] clusters have been synthesized by hydrothermal reaction, structurally described, as well as properties characterized, that have unusual 3D networks with high connectivity (3,12) and (3,13)-connected, respectively. Notably, the unique (3,13)-connected framework is constructed from the (3,12)-connected network analogue and 4,4′-bipyridyl spacer. Magnetic studies show that a dominant antiferromagnetic coupling between Co(II) ions, and the generation of relatively effective noncompensated moments at very low temperature, mainly arises from the cooperative magnetic effect of the intercluster arrangement in the Td−SP-3Ohmixed-geometry-based pentamer. [ABSTRACT FROM AUTHOR]

Five new Mn(II) metal–organic coordination polymers, [Mn(tbip)(bipy)]n(1), {[Mn(tbip)(dpe)]·1.5H2O}n(2), [Mn(tbip)(bpa)]n(3), [Mn(mip)(bpa)]n(4) and {[Mn3(mip)2(Hmip)2(bpp)2(H2O)2]·2H2O}n(5), were prepared through hydrothermal reactions of Mn(II) acetate with H2tbip (H2tbip = 5-tert-butyl isophthalic acid) or H2mip (H2mip = 5-methylisophthalic acid) in the presence of different dipyridyl co-ligands (bipy = 4,4′-bipyridine, dpe = 1,2-bi(4-pyridyl)ethene, bpa = 1,2-bi(4-pyridyl)ethane and bpp = 1,3-di(4-pyridyl)propane). All these compounds were characterized by elemental analysis, IR spectroscopy and X-ray single-crystal diffraction. The structures of 1and 2are constructed of [Mn2(tbip)2]nlayers, which consist of alternate left- and right-handed helical chains, and further pillared by bipy or dpe ligands into a 3D porous framework. Interestingly, there are two different sizes of pores in 1and 2. From the topology point of view, both complexes 1and 2exhibit the rare rob network based on the dimeric [Mn(COO)]2subunits as the 6-connected nodes. The ribbon-like chains having 8- and 16-membered rings in 3and 4result from dimeric Mn(II) units bridged by H2tbip or H2mip ligands, which are connected by the flexible dpa into 2D open layers. Complex 5contains rare isophthalato-bridged trimanganese clusters as building units, which are further linked by mip anions to form a one-dimensional ladder-like chain with less common unidentate coordinated bpp decorated as pendants. The thermal stabilities and X-ray powder diffraction studies indicate that the microporous framework of 2can keep stable even after the loss of guest water molecules. In addition, dominant antiferromagnetic coupling was observed in compounds 1–3and 5. [ABSTRACT FROM AUTHOR]