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 novel three‐dimensional copper(II) coordination polymer with 1,4‐bis(1,2,4‐triazol‐1‐ylmeth­yl)benzene and thio­cyanate

In the title complex, poly[copper(II)‐di‐μ₂‐thio­cyanato‐μ₂‐1,4‐bis­(1,2,4‐triazol‐1‐ylmeth­yl)benzene], [Cu(NCS)₂(C₁₂H₁₂N₆)]_n, the Cu^II atom lies on an inversion centre in a tetra­gonally distorted octa­hedral environment. Four N atoms from thio­cyanate and 1,4‐bis­(1,2,4‐triazol‐1‐ylmeth­yl)benzene (bbtz) ligands fill the equatorial positions, and S atoms from symmetry‐related thio­cyanate ligands fill the axial positions. The benzene ring of the bbtz ligand lies about an inversion centre. Single thio­cyanate bridges link the Cu^II atoms into two‐dimensional sheets containing an unprecedented 16‐membered [Cu₄(μ‐NCS‐N:S)₄] ring. The bbtz ligands further link the two‐dimensional sheets into a three‐dimensional network.     

A novel three‐dimensional cadmium(II) coordination polymer incorporating 1,4‐bis­(1,2,4‐triazol‐1‐ylmethyl)­benzene and thio­cyanate

In the title complex, poly[cadmium(II)‐μ₂‐1,4‐bis­(1,2,4‐triazol‐1‐ylmeth­yl)benzene‐di‐μ₂‐thio­cyanato], [Cd(NCS)₂(C₁₂H₁₂N₆)]_n, the Cd^II atom lies on an inversion centre in a distorted octa­hedral environment. Four N atoms from the thio­cyanate and 1,4‐bis­(1,2,4‐triazol‐1‐ylmeth­yl)benzene (bbtz) ligands occupy the equatorial positions, and two S atoms from symmetry‐related thio­cyanate ligands occupy the axial positions. The benzene ring of the bbtz ligand lies about an inversion centre. Single thio­cyanate bridges link the Cd^II atoms into two‐dimensional sheets containing novel 16‐membered [Cd₄(μ‐NCS‐N:S)₄] rings. The bbtz ligands further link these two‐dimensional sheets into an unprecedented covalent three‐dimensional network for the cadmium–thio­cyanate system.     

A novel two‐dimensional network cadmium(II) coordination polymer containing one 1,4‐bis­(1,2,4‐triazol‐1‐yl)butane and double dicyanamide bridges

In the crystal structure of the title complex, poly[μ‐1,4‐bis­(1,2,4‐triazol‐1‐yl)butane‐di‐μ‐1,5‐dicyanamido‐cadmium(II)], [Cd(C₂N₃)₂(C₈H₁₂N₆)]_n or [Cd(dca)₂(btb)]_n, where dca is dicyanamide and btb is 1,4‐bis­(1,2,4‐triazol‐1‐yl)butane, each Cd^II atom occupies a center of symmetry and is in a six‐coordinated distorted octa­hedral environment. Four N atoms from four dca ligands fill the equatorial positions, and two N atoms from two btb ligands occupy the axial positions. The dca ligands adopt an end‐to‐end coordination mode and link the Cd^II atoms to form a 12‐membered Cd(dca)₂Cd ring, and neighboring rings extend along the b axis to form a [Cd(dca)₂]_n chain. The btb ligands, acting as bridging bidentate ligands, link the Cd^II atoms of adjacent one‐dimensional [Cd(dca)₂]_n chains, forming a rhombic two‐dimensional network.     

Magnetic investigations of a two‐dimensional coordination polymer with a three‐dimensional supramolecular framework: poly[[bis[μ2‐1,4‐bis(1,2,4‐triazol‐1‐yl)butane]bis(thiocyanato‐κN)cobalt(II)] dihydrate]

In the title mixed‐ligand metal–organic polymeric complex, {[Co(NCS)₂(C₈H₁₂N₆)₂]·2H₂O}_n, the asymmetric unit contains a divalent Co^II cation, which sits on an inversion centre, two halves of two crystallographically distinct and centrosymmetric 1,4‐bis(1,2,4‐triazol‐1‐yl)butane (BTB) ligands, one N‐bound thiocyanate ligand and one solvent water molecule. The Co^II atom possesses a distorted {CoN₆} octahedral geometry, with the equatorial positions taken up by triazole N atoms from four different BTB ligands. The axial positions are filled by thiocyanate N atoms. In the crystal, each Co^II atom is linked covalently to four others through the distal donors of the tethering BTB ligands, forming a neutral (4,4)‐topology two‐dimensional rhomboid grid layer motif, which is coincident with the (11) crystal planes. Magnetic investigations show that weak antiferromagnetic coupling exists between Co^II atoms in the complex.     

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 two‐dimensional MnII coordination polymer with 1,2‐bis­(imidazol‐1‐yl)­ethane

In the crystal structure of the title complex, poly­[[di­azido­manganese(II)]‐di‐μ‐1,2‐bis­(imidazol‐1‐yl)­ethane‐κ⁴N³:N^3′], [Mn(N₃)₂(C₈H₁₀N₄)₂]_n or [Mn(N₃)₂(bim)₂]_n, where bim is 1,2‐­bis(imidazol‐1‐yl)­ethane, each Mn^II atom is six‐coordinated in a distorted octahedral coordination environment to four N atoms from four bim ligands and two N atoms from two azide ligands. The Mn^II atoms, which lie on inversion centres, are bridged by four bim ligands to form a two‐dimensional (4,4)‐network. The azide ligands are monodentate (terminal).     

Construction of (3,8)‐connected three‐dimensional cobalt(II) and copper(II) coordination polymers with 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene and benzene‐1,3,5‐tricarboxylate ligands

Coordination polymers (CPs) have been widely studied because of their diverse and adjustable topologies and wide‐ranging applications in luminescence, chemical sensors, magnetism, photocatalysis, gas adsorption and separation. In the present work, two coordination polymers, namely poly[(μ₅‐benzene‐1,3,5‐tricarboxylato‐κ⁶O¹:O^1′:O³:O³:O⁵,O^5′){μ₃‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ³N:N′:N′′}di‐μ₃‐hydroxido‐dicobalt(II)], [Co₂(C₉H₃O₆)(OH)(C₁₂H₁₂N₆)]_n or [Co₂(btc)(OH)(mtrb)]_n, (1), and poly[[diaquabis(μ₃‐benzene‐1,3,5‐tricarboxylato‐κ³O¹:O³:O⁵)bis{μ₃‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ³N:N′:N′′}tetra‐μ₃‐hydroxido‐tetracopper(II)] monohydrate], {[Cu₄(C₉H₃O₆)₂(OH)₂(C₁₂H₁₂N₆)₂(H₂O)₂]·H₂O}_n or {[Cu₄(btc)₂(OH)₂(mtrb)₂(H₂O)₂]·H₂O}_n, (2), were synthesized by the hydrothermal method using 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene (mtrb) and benzene‐1,3,5‐tricarboxylate (btc^3?). CP (1) exhibits a (3,8)‐coordinated three‐dimensional (3D) network of the 3,8T38 topological type, with a point symbol of {4,5,6}₂{4²·5⁶·6¹⁶·7²·8²}, based on the tetranuclear hydroxide cobalt(II) cluster [Co₄(μ₃‐OH)₂]. CP (2) shows a (3,8)‐coordinated tfz‐d topology, with a point symbol of {4₃}₂{4⁶·6¹⁸·8⁴}, based on the tetranuclear hydroxide copper(II) cluster [Cu₄(μ₃‐OH)₂]. The different (3,8)‐coordinated 3D networks based on tetranuclear hydroxide–metal clusters of (1) and (2) are controlled by the different central metal ions [Co^II for (1) and Cu^II for (2)]. The thermal stabilities and solid‐state optical diffuse‐reflection spectra were measured. The energy band gaps (E_g) obtained for (1) and (2) were 2.72 and 2.29 eV, respectively. CPs (1) and (2) exhibit good photocatalytic degradation of the organic dyes methylene blue (MB) and rhodamine B (RhB) under visible‐light irradiation.     

(4,4′‐Bipyridine)dichloroman­ganese(II), a two‐dimensional ­coordination polymer

The title compound, [MnCl₂(C₁₀H₈N₂)]_n, crystallizes with a two‐dimensional network constructed from linear chains of edge‐sharing MnCl₄ square‐planar units cross‐linked by bidentate 4,4′‐bi­pyridine bridges. The Mn atom and the bipyridine moieties lie on sites with 222 crystallographic symmetry; the Cl atom lies on a twofold axis. The bi­pyridine mol­ecule is twisted about the central C—C bond by 33.5 (3)°.     

Synthesis and crystal structure of a two‐dimensional sodium coordination polymer of 4,4′‐(diazenediyl)bis(1H‐1,2,4‐triazol‐5‐one)

The crystal engineering of coordination polymers has aroused interest due to their structural versatility, unique properties and applications in different areas of science. The selection of appropriate ligands as building blocks is critical in order to afford a range of topologies. Alkali metal cations are known for their mainly ionic chemistry in aqueous media. Their coordination number varies depending on the size of the binding partners, and on the electrostatic interaction between the ligands and the metal ions. The two‐dimensional coordination polymer poly[tetra‐μ‐aqua‐[μ₄‐4,4′‐(diazenediyl)bis(5‐oxo‐1H‐1,2,4‐triazolido)]disodium(I)], [Na₂(C₄H₂N₈O₂)(H₂O)₄]_n, (I), was synthesized from 4‐amino‐1H‐1,2,4‐triazol‐5(4H)‐one (ATO) and its single‐crystal structure determined. The mid‐point of the imino N=N bond of the 4,4′‐(diazenediyl)bis(5‐oxo‐1H‐1,2,4‐triazolide) (ZTO²⁻) ligand is located on an inversion centre. The asymmetric unit consists of one Na⁺ cation, half a bridging ZTO²⁻ ligand and two bridging water ligands. Each Na⁺ cation is coordinated in a trigonal antiprismatic fashion by six O atoms, i.e. two from two ZTO²⁻ ligands and the remaining four from bridging water ligands. The Na⁺ cation is located near a glide plane, thus the two bridging O atoms from the two coordinating ZTO²⁻ ligands are on adjacent apices of the trigonal antiprism, rather than being in an anti configuration. All water and ZTO²⁻ ligands act as bridging ligands between metal centres. Each Na⁺ metal centre is bridged to a neigbouring Na⁺ cation by two water molecules to give a one‐dimensional [Na(H₂O)₂]_n chain. The organic ZTO²⁻ ligand, an O atom of which also bridges the same pair of Na⁺ cations, then crosslinks these [Na(H₂O)₂]_n chains to form two‐dimensional sheets. The two‐dimensional sheets are further connected by intermolecular hydrogen bonds, giving rise to a stabile hydrogen‐bonded network.     

A three‐dimensional cadmium coordination polymer based on 1,4‐bis(1,2,4‐triazol‐1‐yl)but‐2‐ene and benzene‐1,3,5‐tricarboxylic acid

The Cd^II three‐dimensional coordination poly[[[μ₄‐1,4‐bis(1,2,4‐triazol‐1‐yl)but‐2‐ene]bis(μ₃‐5‐carboxybenzene‐1,3‐dicarboxylato)dicadmium(II)] dihydrate], {[Cd₂(C₉H₄O₆)₂(C₈H₁₀N₆)]·2H₂O}_n , (I), has been synthesized by the hydrothermal reaction of Cd(NO₃)₂·4H₂O, benzene‐1,3,5‐tricarboxylic acid (1,3,5‐H₃BTC) and 1,4‐bis(1,2,4‐triazol‐1‐yl)but‐2‐ene (1,4‐btbe). The IR spectrum suggests the presence of protonated carboxylic acid, deprotonated carboxylate and triazolyl groups. The purity of the bulk sample was confirmed by elemental analysis and X‐ray powder diffraction. Single‐crystal X‐ray diffraction analysis reveals that the Cd^II ions adopt a five‐coordinated distorted trigonal–bipyramidal geometry, coordinated by three O atoms from three different 1,3,5‐HBTC²⁻ ligands and two N atoms from two different 1,4‐btbe ligands; the latter are situated on centres of inversion. The Cd^II centres are bridged by 1,3,5‐HBTC²⁻ and 1,4‐btbe ligands into an overall three‐dimensional framework. When the Cd^II centres and the tetradentate 1,4‐btbe ligands are regarded as nodes, the three‐dimensional topology can be simplified as a binodal 4,6‐connected network. Thermogravimetric analysis confirms the presence of lattice water in (I). Photoluminescence studies imply that the emission of (I) may be ascribed to intraligand fluorescence.     

A new three‐dimensional zinc(II) coordination polymer involving 2‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]‐1H‐benzimidazole and benzene‐1,4‐dicarboxylate ligands

Metal–organic frameworks (MOFs) based on multidentate N‐heterocyclic ligands involving imidazole, triazole, tetrazole, benzimidazole, benzotriazole or pyridine present intriguing molecular topologies and have potential applications in ion exchange, magnetism, gas sorption and storage, catalysis, optics and biomedicine. The 2‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]‐1H‐benzimidazole (tmb) ligand has four potential N‐atom donors and can act in monodentate, chelating, bridging and tridentate coordination modes in the construction of complexes, and can also act as both a hydrogen‐bond donor and acceptor. In addition, the tmb ligand can adopt different coordination conformations, resulting in complexes with helical structures due to the presence of the flexible methylene spacer. A new three‐dimensional coordination polymer, poly[[bis(μ₂‐benzene‐1,4‐dicarboxylato)‐κ⁴O¹,O^1′:O⁴,O^4′;κ²O¹:O⁴‐bis{μ₂‐2‐[(1H‐1,2,4‐triazol‐1‐yl)methyl‐κN⁴]‐1H‐benzimidazole‐κN³}dizinc(II)] trihydrate], {[Zn(C₈H₄O₄)(C₁₀H₉N₅)]·1.5H₂O}_n, has been synthesized by the reaction of ZnCl₂ with tmb and benzene‐1,4‐dicarboxylic acid (H₂bdic) under solvothermal conditions. There are two crystallographically distinct bdic²⁻ ligands [bdic²⁻(A) and bdic²⁻(B)] in the structure which adopt different coordination modes. The Zn^II ions are bridged by tmb ligands, leading to one‐dimensional helical chains with different handedness, and adjacent helices are linked by bdic²⁻(A) ligands, forming a two‐dimensional network structure. The two‐dimensional layers are further connected by bdic²⁻(B) ligands, resulting in a three‐dimensional framework with the topological notation 6⁶. The IR spectra and thermogravimetric curves are consistent with the results of the X‐ray crystal structure analysis and the title polymer exhibits good fluorescence in the solid state at room temperature.     

The two‐dimensional coordination polymer poly[[bis(3‐methyl­pyridine)­cadmium(II)]‐tetra‐μ‐cyano‐nickel(II)]

The title complex, [CdNi(CN)₄(C₆H₇N)₂]_n, adopts a slightly distorted octahedral geometry around the Cd centre. Four cyanide N atoms occupy the equatorial coordination sites around the Cd centre. The structure consists of corrugated and cyanide‐bridged polymeric networks made up of tetracyano­nickelate ions coordinated to cadmium, with the Ni ion coordinated by four cyanide ligands in a square‐planar arrangement. The Cd and Ni atoms occupy special positions of 2/m site symmetry. The 3‐methyl­pyridine group, except for two methyl H atoms, lies on a crystallographic mirror plane. The 3‐methyl­pyridine molecules, bound to cadmium in trans positions, are located on both sides of the network. The bonding in the networks occurs because of a departure of the Ni—C—N—Cd sequence of atoms from linearity at the C and N atoms.     

Synthesis,crystal structure and characterization of a three‐dimensional CdII coordination polymer constructed from 2,5‐bis(1H‐1,2,4‐triazol‐1‐yl)terephthalate

Bifunctional organic ligands are very popular for the design of coordination polymers because they allow the formation of a great diversity of structures. In the title coordination polymer, the new bifunctional inversion‐symmetric ligand 2,5‐bis(1H‐1,2,4‐triazol‐1‐yl)terephthalic acid (abbreviated as H₂bttpa) links Cd^II cations, giving rise to the three‐dimensional Cd^II coordination polymer catena‐poly[diaqua[μ₄‐2,5‐bis(1H‐1,2,4‐triazol‐1‐yl)terephthalato‐κ⁴O¹:O⁴:N⁴:N^4′]cadmium(II)], [Cd(C₁₂H₆N₆O₄)(H₂O)₂]_n or [Cd(bttpa)(H₂O)₂]_n. The asymmetric unit consists of half a Cd^II cation, half a bttpa²⁻ ligand and one coordinated water molecule. The Cd^II cation is located on a twofold axis and is hexacoordinated in a distorted octahedral environment of four O and two N atoms. Four different bttpa²⁻ ligands contribute to this coordination, with two carboxylate O atoms in trans positions and two triazole N atoms in cis positions. Two aqua ligands in cis positions complete the coordination sphere. The fully deprotonated bttpa²⁻ ligand sits about a crystallographic centre of inversion and links two Cd^II cations to form a chain in a μ₂‐terephthalato‐κ²O¹:O⁴ bridge. This chain extends in the other two directions via the triazole heterocycles, producing a three‐dimensional framework. O—H…O hydrogen bonds and weak C—H…N interactions stabilize the three‐dimensional crystal structure. The FT–IR spectrum, X‐ray powder pattern, thermogravimetric behaviour and solid‐state photoluminescence of the title polymer have been investigated. The photoluminescence is enhanced and red‐shifted with respect to the uncoordinated ligand.     

Poly[[{μ4‐3‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]benzoato}zinc(II)] hemihydrate]: a novel two‐dimensional framework formed by self‐association of zinc(II) sulfate with 3‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]benzoic acid

The title novel two‐dimensional coordination polymer, {[Zn₂(C₁₀H₈N₃O₂)₄]·H₂O}_n, features a {Zn₂L₂} bimetallic ring repeat unit {L is the 3‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]benzoate ligand}. Each Zn^II cation of the bimetallic ring is further bonded to two other L ligands, resulting in a novel infinite two‐dimensional network structure with two channels of different sizes. The crystallographically unique Zn^II atom is thus six‐coordinated in a distorted octahedral environment of four carboxylate O atoms and two triazole N atoms. Two of these networks interpenetrate in an orthogonal arrangement to form the full three‐dimensional framework, with disordered water molecules located in the channels.     

A novel two‐dimensional (4,4) network based on dinuclear cadmium secondary building units: poly[(μ5‐benzene‐1,4‐diacetato)[μ2‐1,4‐bis(1,2,4‐triazol‐1‐yl)butane]cadmium(II)]

In the title mixed‐ligand metal–organic polymeric compound, [Cd(C₁₀H₈O₄)(C₈H₁₂N₆)]_n or [Cd(PBEA)(BTB)]_n [H₂PBEA is benzene‐1,4‐diacetic acid and BTB is 1,4‐bis(1,2,4‐triazol‐1‐yl)butane], the asymmetric unit contains one Cd^II ion, one BTB molecule and one PBEA²⁻ anion. The Cd^II ion is in a slightly distorted pentagonal–bipyramidal geometry, coordinated by five carboxylate O atoms from three distinct PBEA²⁻ anions and by two BTB N atoms. There are two coordination patterns for the carboxylate groups of the PBEA²⁻ ligand, one being a μ₁‐η¹:η¹ chelating mode and the other a μ₂‐η²:η¹ bridging mode, while the BTB molecule shows a trans–trans–trans conformation. The crystal structure is constructed from the secondary building unit (SBU) [Cd₂(CO₂)₄N₂O₂], in which the two metal centres are held together by two PBEA²⁻ linkers. The SBU is connected by BTB and PBEA²⁻ bridges to form a two‐dimensional grid‐like (4,4) layer with meshes of dimensions 14.69 × 11.28 Å.     

A new two‐dimensional managnese(II) coordination polymer constructed by 2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylate)

In recent years, N‐heterocyclic carboxylate ligands have attracted much interest in the preparation of new coordination polymers since they contain N‐atom donors, as well as O‐atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. A new two‐dimensional coordination polymer, namely poly[[μ₃‐2,2′‐(1,2‐phenylene)bis(4‐carboxy‐1H‐imidazole‐5‐carboxylato)‐κ⁶O⁴,N³,N^3′,O^4′:O⁵:O^5′]manganese(II)], [Mn(C₁₆H₈N₄O₈)]_n or [Mn(H₄Phbidc)]_n, has been synthesized by the reaction of Mn(OAc)₂·4H₂O (OAc is acetate) with 2,2′‐(1,2‐phenylene)bis(1H‐imidazole‐4,5‐dicarboxylic acid) (H₆Phbidc) under solvothermal conditions. In the polymer, each Mn^II ion is six‐coordinated by two N atoms from one H₄Phbidc²⁻ ligand and by four O atoms from three H₄Phbidc²⁻ ligands, forming a significantly distorted octahedral MnN₂O₄ coordination geometry. The Mn^II ions are linked by hexadentate H₄Phbidc²⁻ ligands, leading to a two‐dimensional structure parallel to the ac plane. In the crystal, adjacent layers are further connected by N—H…O hydrogen bonds, forming a three‐dimensional structure in the solid state.     

Monomeric bis(2,4‐pentane­dionato)­cobalt(II)

The title compound, [Co(C₅H₇O₂)₂], contains isolated mol­ecules. The Co atom is located on a centre of symmetry with the bidentate ligands adopting a square‐planar geometry about the Co atom.     

A new two‐dimensional manganese(II) coordination polymer based on thiophene‐3,4‐dicarboxylic acid

A novel manganese coordination polymer, poly[(μ₅‐thiophene‐3,4‐dicarboxylato)manganese(II)], [Mn(C₆H₂O₄S)]_n, was synthesized hydrothermally using 3,4‐thiophenedicarboxylate (3,4‐tdc²⁻) as the organic linker. The asymmetric unit of the complex contains an Mn²⁺ cation and one half of a deprotonated 3,4‐tdc²⁻ anion, both residing on a twofold axis. Each Mn²⁺ centre is six‐coordinated by O atoms of bridging/chelating carboxylate groups from five 3,4‐tdc²⁻ anions, forming a slightly distorted octahedron. The Mn²⁺ centres are bridged by 3,4‐tdc²⁻ anions to give an infinite two‐dimensional layer which incorporates one‐dimensional Mn–O gridlike chains, and in which the 3,4‐tdc²⁻ anion adopts a novel hexadentate chelating and μ₅‐bridging coordination mode. The fully deprotonated 3,4‐tdc²⁻ anion exhibits unexpected efficiency as a ligand towards the Mn²⁺ centres, which it coordinates through all of its carboxylate O atoms to provide the novel coordination mode. The IR spectrum of the complex is also reported.     

A novel parallel interpenetrating two‐dimensional (4,4) network: poly[[μ2‐1,4‐bis(imidazol‐1‐ylmethyl)benzene](μ2‐naphthalene‐1,4‐dicarboxylato)zinc(II)]

In the title coordination compound, [Zn(C₁₂H₆O₄)(C₁₄H₁₄N₄)]_n, the two Zn^II centers exhibit different coordination environments. One Zn^II center is four‐coordinated in a distorted tetrahedral environment surrounded by two carboxylate O atoms from two different naphthalene‐1,4‐dicarboxylate (1,4‐ndc) anions and two N atoms from two distinct 1,4‐bis(imidazol‐1‐ylmethyl)benzene (1,4‐bix) ligands. The coordination of the second Zn^II center comprises two N atoms from two different 1,4‐bix ligands and three carboxylate O atoms from two different 1,4‐ndc ligands in a highly distorted square‐pyramidal environment. The 1,4‐bix ligand and the 1,4‐ndc anion link adjacent Zn^II centers into a two‐dimensional four‐connected (4,4) network. The two (4,4) networks are interpenetrated in a parallel mode.