A new three‐dimensional cobalt(II) coordination polymer with a 4‐connected CdSO4‐like topology

The title cobalt(II) coordination polymer, poly[[diaquacobalt(II)]‐μ₄‐3,3′‐(p‐phenylene)diacrylato], [Co(C₁₂H₈O₄)(H₂O)₂]_n, was obtained by reaction of Co(NO₃)₂·6H₂O and 3,3′‐(p‐phenylene)diacrylic acid (H₂L) under hydrothermal conditions. Each Co^II cation sits on a centre of inversion and is hexacoordinated by six O‐atom donors in an octahedral geometry. The Co^II centres are connected by four centrosymmetric L²⁻ anions, resulting in a three‐dimensional framework structure. The coordinated water molecules and carboxylate O atoms form hydrogen‐bond interactions, stabilizing the structure of the three‐dimensional framework. Topologically, the framework represents a rare example of the three‐dimensional 4‐connected CdSO₄ network type. The metal cations and the organic ligand both show in‐plane coordination with respect to the extended structure.     

A novel cadmium(II) coordination polymer with a four‐connected (4,4)‐net based on a trinuclear cadmium(II) node

In the title cadmium(II) coordination polymer, poly[tri‐μ₄‐adipato‐bis(2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene‐κ²N⁷,N⁸)tricadmium(II)], [Cd₃(C₆H₈O₄)₃(C₁₉H₁₂N₄)₂]_n, one of the Cd atoms is in a distorted pentagonal bipyramidal coordination environment, surrounded by five O atoms from three adipate (adip) ligands and two N atoms from one 2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene (L) ligand. A second Cd atom occupies an inversion center and is coordinated by six O atoms from six adip ligands in a distorted octahedral geometry. The carboxylate ends of the adip ligands link Cd^II atoms to form unique trinuclear Cd^II clusters, which are further bridged by the adip linkers to produce a two‐dimensional layer structure. Topologically, each trinuclear Cd^II cluster is connected to four others through six adip ligands, thus resulting in a unique two‐dimensional four‐connected framework of (4,4)‐topology. This work may help the development of the coordination chemistry of 1,10‐phenanthroline derivatives.     

A novel cobalt(II) coordination polymer containing the fumarate anion and o‐phenanthroline

The self‐assembly of three crystallographically distinct fumar­ate ions, two unique cobalt(II) ions and two unique o‐phen­;anthroline mol­ecules results in a two‐dimensional polymeric structure with the formula [Co₂(C₄H₂O₄)₂(C₁₂H₈N₂)₂]_n, namely di‐μ‐fumatato‐bis(o‐phenanthroline)­dicobalt(II). The Co atoms are at the nodes of a two‐dimensional array linked by coordinated fumarate ligands. Each Co atom is coordinated in a distorted octahedral manner to four fumarate O atoms and two N atoms from the chelating phenanthroline ligands.     

A novel two‐dimensional zinc(II) coordination polymer with 6‐mercaptonicotinic acid

The novel title Zn^II coordination polymer, poly[bis(μ‐6‐thioxo‐1,6‐dihydropyridine‐3‐carboxylato‐κ²S:O)zinc(II)], [Zn(C₆H₄NO₂S)₂]_n, consists of two crystallographically independent zinc centers and two 6‐mercaptonicotinate (Hmna⁻) ligands. Each Zn^II atom is four‐coordinated and lies at the center of a distorted tetrahedral ZnS₂O₂ coordination polyhedron, bridged by four Hmna⁻ ligands to form a two‐dimensional (4,4)‐network. Each Hmna⁻ ion acts as a bridging bidentate ligand, coordinating to two Zn^II atoms through the S atom and a carboxyl O atom. The metal centers reside on twofold rotation axes. The coordination mode of the S atoms and N—H...O hydrogen‐bonding interactions between the protonated N atoms and the uncoordinated carboxyl O atoms give the extended structure a wavelike form.     

A novel (3,6)‐connected CdII coordination polymer based on an ether‐linked tricarboxylate ligand: synthesis,topology and luminescence sensing properties in aqueous solution

A novel three‐dimensional coordination polymer, namely, poly[[diaquabis(μ‐4,4′‐bipyridine)bis{μ₃‐5‐[(2‐carboxyphenoxy)methyl]isophthalato}tricadmium(III)] dimethylformamide monosolvate 2.5‐hydrate], {[Cd₃(C₁₆H₉O₇)₂(C₁₀H₈N₂)₂(H₂O)₂]·2C₃H₇NO·5H₂O}_n, was obtained by the reaction of ether‐linked 5‐[(2‐carboxyphenoxy)methyl]isophthalic acid (H₃L) with Cd^II salts in the presence of 4,4′‐bipyridine (bpy) under solvothermal conditions. In this complex, the Cd^II centres are connected by the carboxylate ligands to form two‐dimensional wave‐like layers, which are pillared by bpy ligands and extended into a rare three‐dimensional (3,6)‐connected sqc27 framework. The complex demonstrated good water stability and strong luminescence emissions. It not only possesses excellent luminescence sensing activities toward Fe³⁺ and Cr₂O₇^2? in aqueous solution, but can also distinguish between Cr₂O₇^2? and CrO₄^2? by luminescence. Furthermore, it could be simply and quickly regenerated at least five times. A study of the sensing mechanism indicated that luminescence quenching may be related to the energy competition between the complex and sensing analytes.     

A novel two‐dimensional cobalt(II) coordination polymer with 1,4‐bis(1,2,4‐triazol‐1‐yl­methyl)­benzene

In the crystal structure of the title complex, poly­[[di­azidocobalt(II)]‐di‐μ‐1,4‐bis(1,2,4‐triazol‐1‐yl­methyl)­benzene‐κ⁴N⁴:N^4′], [Co(N₃)₂(bbtz)₂]_n, where bbtz is 1,4‐bis(1,2,4‐triazol‐1‐yl­methyl)­benzene (C₁₂H₁₂N₆), the Co^II atom, which lies on an inversion centre, is six‐coordinated by four N atoms from four bbtz ligands and by two N atoms from two azide ligands, in a distorted octahedral coordination environment. The Co^II atoms are bridged by four bbtz ligands to form a two‐dimensional [4,4]‐network.     

A novel one‐dimensional zigzag coordination polymer of copper(II) with di­methyl­glyoxime

A novel metal‐organic based polymeric complex, namely catena‐poly­[[bis(μ₄‐di­methyl­glyoximato)­bis(μ₂‐di­methyl­gly­oxi­mato)­bis­(di­methyl­glyoxime)­tetracopper(II)] diperchlorate dihydrate], {[Cu₄(dmg)₂(Hdmg)₂(H₂dmg)₂](ClO₄)₂·2H₂O}_∞ (H₂dmg is di­methyl­glyoxime, C₂H₈N₂O₂), has been synthesized and characterized by single‐crystal X‐ray diffraction methods. The complex is a one‐dimensional zigzag chain coordination polymer, in which the tetranuclear repeat unit is a centrosymmetric Cu₄ moiety coordinated to di­methyl­glyoxime ligands only. These units are linked by double Cu—O—Cu bridges in a centrosymmetric rectangular ­junction.     

A novel cadmium(II) coordination polymer containing two kinds of independent one‐dimensional chain

The structure of the title compound, catena‐poly[[cadmium(II)‐di‐μ‐chlorido‐μ‐(1,4‐diazoniabicyclo[2.2.2]octane‐1‐carboxylato)] [[aquachloridocadmium(II)]‐di‐μ‐chlorido] dihydrate], {[Cd(C₈H₁₅N₂O₂)Cl₂][CdCl₃(H₂O)]·2H₂O}_n, contains two kinds of independent one‐dimensional chain, viz. {[Cd(C₈H₁₅N₂O₂)Cl₂]⁺}_n and {[CdCl₃(H₂O)]⁻}_n, and uncoordinated water molecules. Each Cd^II cation in the {[Cd(C₈H₁₅N₂O₂)Cl₂]⁺}_n chain is octahedrally coordinated by two pairs of bridging chloride ligands and two O atoms from different bridging carboxylate groups. Cd^II cations in the {[CdCl₃(H₂O)]⁻}_n chain are also octahedrally surrounded by four bridging chloride ligands, one terminal chloride ligand and one coordinated water molecule. Hydrogen bonds between solvent water molecules and these two independent chains generate a three‐dimensional framework containing two‐dimensional zigzag layers.<!?tpb=18pt>     

A novel cobalt(II)-molybdenum(V) phosphate organic-inorganic hybrid polymer

A new organic-inorganic hybrid cobalt(II)-molybdenum(V) phosphate polymer incorporating piperazine (pip), (H₂pip)₃[Co₃Mo₁₂O₂₄(OH)₆(PO₄)₈(H_1.5pip)₄]·5(H₂O), was prepared under hydrothermal conditions. As revealed by single-crystal X-ray diffraction studies, the material is modular, built from a secondary building block composed of two anionic hexameric polyoxomolybdophosphate [Mo₆O₁₂(OH)₃(PO₄)₄]⁹⁻ moieties, bridged by a central octahedral Co²⁺ centre. The sandwich-type {Co[Mo₆O₁₂(OH)₃(PO₄)₄]₂}¹⁶⁻ dimers are connected via tetrahedral Co²⁺ metal centres, forming an infinite one-dimensional polymer. The compound constitutes the first example of a reduced sandwich-type cobalt-molybdenum phosphate in which the organic moiety (pip) is effectively coordinated to the inorganic backbone of the polymer, in this case via the tetrahedrally coordinated Co²⁺ centres. The magnetic behaviour of this material was investigated in the temperature range 4-298 K.     

An acylamide metal–organic framework with an unprecedented four‐connecting trinodal topology and amide oxygen coordination

The three‐dimensional Zn^II coordination polymer poly[[bis(μ₂‐benzene‐1,4‐dicarboxylato){μ₄‐N¹,N³,N⁵‐tris[(pyridin‐3‐yl)methyl]benzene‐1,3,5‐tricarboxamide}dizinc(II)] monohydrate], {[Zn₂(C₈H₄O₄)₂(C₂₇H₂₄N₆O₃)]·H₂O}_n, is characterized by a rare (4,4,4)‐connected (4.6².7².8)(4.6².7³)(4².6².7²) topology. The tricarboxamide ligand adopts an unprecedented tetradentate coordination mode, with one carboxamide O atom participating in the coordination. The polymer was further characterized by thermogravimetric and solid‐state luminescence analysis.     

Two 2D cobalt(II) coordination frameworks with unusual binodal network topology: synthesis, structures, and catalytic properties

Two coordination polymers, namely {[Co₂(L1)₂(btec)]?4H₂O}_n (1) and [Co(L2)(btec)_0.5(H₂O)]_n (2) [L1 = 1,3-bis(5,6-dimethylbenzimidazole)propane, btec = 1,2,4,5-benzenetetracarboxylate, L2 = 1,2-bis(5,6-dimethylbenzimidazole-1-ylmethyl)benzene], have been synthesized and characterized by physicochemical and spectroscopic methods as well as single-crystal diffraction. The cobalt(II) atoms display different environments with a tetrahedral geometry in 1 and trigonal–bipyramidal geometry in 2. Both complexes show 2D layer structures with a rare binodal (3,4)-connected topology structure, named 3,4L13. Their catalytic activities were tested for the degradation of congo red azo dye in a Fenton-like process.     

Interaction of cobalt(II) and nickel(II) with a gamma-linked, bis-beta-diketone ligand to yield an unusual coordination motif

Discrete cobalt(II) and nickel(II) complexes of type ML (where L is a bis(2,4-pentanedionate) derivative incorporating a -SCH2CH2S- bridge between the gamma-carbons of respective beta-diketone units) have been synthesised and represent the first examples in which a gamma-substituted, thioether-containing beta-diketone ligand coordinates via a sulfur and oxygen donor in preference to the classical coordination mode involving both beta-diketonate oxygens.     

A novel nickel(II) coordination polymer incorporating 1,4‐phenylene­diacetic acid and 1,10‐phenanthroline

The title nickel(II) coordination polymer, viz. poly[[bis­(1,10‐phenanthroline)tris­(μ₃‐1,4‐phenyl­enediacetato)trinickel(II)] dihydrate], {[Ni₃(C₁₀H₈O₄)₃(C₁₂H₈N₂)₂]·2H₂O}_n, consists of linear trinuclear building blocks with two crystallographically unique Ni atoms. One Ni^II atom and the geometric centre of one 1,4‐phenyl­enediacetate ligand in the trinuclear unit both lie on inversion centres, while the other unique Ni^II atom lies near the inversion centre, together with another 1,4‐phenyl­enediacetate ligand. Each pair of adjacent trinuclear units is bridged by 1,4‐phenyl­enediacetate ligands, forming two kinds of infinite chains along the a and b axes, respectively. These two kinds of chains crosslink to yield a two‐dimensional network in the ab plane. The two‐dimensional sheets further stack along the c axis viaπ–π stacking inter­actions and hydrogen bonds, forming a three‐dimensional supramolecular structure.     

A three‐dimensional pyrazine‐2,5‐dicarboxylate CdII coordination framework with new (4,4,4)‐connected three‐nodal topology

Poly[(μ₄‐pyrazine‐2,5‐dicarboxylato)cadmium(II)], [Cd(C₆H₂N₂O₄)]_n or [Cd(pzdc)]_n (pzdc is the pyrazine‐2,5‐dicarboxylate dianion), has been synthesized hydrothermally. The asymmetric unit consists of a Cd^II atom and two independent halves of pzdc ligands that can be expanded via inversion through the centres of the ligands so that each ligand binds to four Cd^II atoms with the same binding mode using six donor atoms. The Cd^II centre is in a distorted octahedral coordination geometry with four O‐ and two N‐atom donors from four pzdc ligands. The infinite linkage of the metal atoms and ligands forms a three‐dimensional framework with a rectangular channel which is so narrow that there is no measurable void space in the overall structure. This coordination polymer represents the first example of (4,4,4)‐connected three‐nodal framework.     

Crystal structure and magnetic properties of Co(II) coordination polymer with CsCl-like topology

One Co(II) coordination polymer with 4-hydroxypyridine-2,6-dicarboxylic acid (H₃L)-[Co_1.5L(H₂O)₄]_n (1) has been fabricated under hydrothermal condition through reaction of Co(OH)₂ and H₃L with mole ratio of 1?:?1. Single-crystal X-ray diffraction analysis reveals that 1 crystallizes in triclinic space group Pī with a 1-D stair-like structure and rich hydrogen bonding interactions expand the 1-D structure to a CsCl-like 8-connected topology. Magnetic properties of 1 have been studied showing antiferromagnetic exchange interaction between Co(II) ions.     

A one‐dimensional zigzag coordination polymer of di­aqua­(pyridine‐2,3‐di­carboxyl­ato)­cobalt(II)

The asymmetric unit of the title one‐dimensional coordination polymer, catena‐poly­[[μ‐pyridine‐2,3‐di­carb­oxyl­ato‐1κO:2κ²N,O′‐bis­[di­aqua­cobalt(II)]]‐μ‐pyridine‐2,3‐di­carboxyl­ato‐1κ²N,O:2κO′:1′κO′], [Co(C₇H₃NO₄)(H₂O)₂]_n, is composed of a cobalt(II) ion, a pyridine‐2,3‐di­carboxyl­ate dianion and two water mol­ecules. The polymer has a zigzag structure consisting of a chain of edge‐fused rings, and the polymer chains are linked by O—H⃛O hydrogen bonds into a three‐dimensional framework.     

A double‐layered zinc(II) coordination polymer with the ligand 3,5‐bis(carboxylatomethoxy)benzoate

In the title compound, poly[hexaaquabis[μ₄‐3,5‐bis(carboxylatomethoxy)benzoato]trizinc(II)], [Zn₃(C₁₁H₇O₈)₂(H₂O)₆]_n, there are two crystallographically distinct Zn^II cations which are bridged by polycarboxylate ligands in a μ₄‐bridging mode. A pair of ligands bridges adjacent Zn atoms to give centrosymmetric dimetal building blocks which act as four‐connected nodes to be further interlinked into a two‐dimensional double‐layered framework with (4,4) topology. Other Zn atoms, lying on inversion centres, occupy the cavities of this topological structure. This submission shows a versatile polycarboxylate ligand with rigid and flexible functional groups, the co‐operation and complementarity of which would meet the coordination requirements of a variety of topological structures.     

A novel copper(II) coordination polymer with 2,2′‐bipyridyl‐3,3′‐di­carboxylic acid

A novel copper(II) coordination polymer, poly­[[[aqua­copper(II)]‐μ₃‐2,2′‐bipyridyl‐3,3′‐di­carboxyl­ato‐κ⁴N,N′:O:O′] dihydrate], {[Cu(C₁₂H₆N₂O₄)(H₂O)]·2H₂O}_n, was obtained by the reaction of CuCl₂·2H₂O and 2,2′‐bipyridyl‐3,3′‐di­carboxylic acid (H₂L) in water. In the mol­ecule, each Cu^II atom is five‐coordinated and lies at the centre of a square‐pyramidal basal plane, bridged by three L ligands to form a two‐dimensional (4,4)‐network. Each L moiety acts as a bridging tetradentate ligand, coordinating to three Cu^II atoms through its two aromatic N atoms and two O atoms of the two carboxyl groups. The two‐dimensional square‐grid sheets superimpose in an off‐set fashion through the inorganic water layer.     

A novel two‐dimensional nickel(II) coordination polymer with 1,4‐bis(1,2,4‐triazol‐1‐ylmethyl)benzene and azide ligands

The coordination geometry of the Ni^II atom in the title complex, poly[diazidobis[μ‐1,4‐bis(1,2,4‐triazol‐1‐ylmethyl)benzene‐κ²N⁴:N^4′]nickel(II)], [Ni(N₃)₂(C₁₂H₁₂N₆)₂]_n, is a distorted octahedron, in which the Ni^II atom lies on an inversion centre and is coordinated by four N atoms from the triazole rings of two symmetry‐related pairs of 1,4‐bis(1,2,4‐triazol‐1‐ylmethyl)benzene (bbtz) ligands and two N atoms from two symmetry‐related monodentate azide ligands. The Ni^II atoms are bridged by four bbtz ligands to form a two‐dimensional (4,4)‐network.     

A thermally stable three‐dimensional cobalt(II) coordination polymer based on the V‐shaped ligand 4‐(4‐carboxyphenoxy)isophthalate

A new cobalt(II) coordination polymer (CP), poly[[bis[μ₆‐4‐(4‐carboxylatophenoxy)benzene‐1,3‐dicarboxylato‐κ⁶O¹:O¹:O³:O^3′:O⁴:O^4′]bis(1,10‐phenanthroline‐κ²N,N′)tricobalt(II)] 0.72‐hydrate], {[Co₃(C₁₅H₇O₇)₂(C₁₂H₈N₂)₂]·0.72H₂O}_n, (I), is constructed from Co^II ions and 4‐(4‐carboxyphenoxy)isophthalate (cpoia³⁻) and 1,10‐phenanthroline (phen) ligands. Based on centrosymmetric trinuclear [Co₃(phen)₂(COO)₆] secondary building units (SBUs), the structure of (I) is a three‐dimensional CP with a (3,6)‐connected net and point symbol (4².6)₂(4⁴.6².8⁷.10²). The positions of four [Co₃(phen)₂(COO)₆] SBUs and four cpoia³⁻ ligands reproduce a Chinese‐knot‐shaped arrangement along the ab plane. (I) has been characterized by single‐crystal X‐ray diffraction, IR spectroscopy, powder X‐ray diffraction (PXRD) and thermostability analysis. It shows a good thermal stability from room temperature to 673 K. In addition, the temperature dependence of the magnetic properties was measured.