The two‐dimensional coordination polymer poly[diaqua(μ2‐1H‐imidazo[4,5‐f][1,10]phenanthroline)‐μ4‐sulfato‐μ3‐sulfato‐dicadmium(II)]

In the title coordination polymer, [Cd₂(SO₄)₂(C₁₃H₈N₄)(H₂O)₂]_n, there are two crystallographically independent Cd^II centres with different coordination geometries. The first Cd^II centre is hexacoordinated by four O atoms of four sulfate ligands, one water O atom and one N atom of a 1H‐imidazo[4,5‐f][1,10]phenanthroline (IP) ligand, giving a distorted octahedral coordination environment. The second Cd^II centre is heptacoordinated by four O atoms of three sulfate ligands, one water O atom and two N atoms of one chelating IP ligand, resulting in a distorted monocapped anti‐trigonal prismatic geometry. The symmetry‐independent Cd^II ions are bridged in an alternating fashion by sulfate ligands, forming one‐dimensional ladder‐like chains which are connected through the IP ligands to form two‐dimensional layers. These two‐dimensional layers are linked by interlayer hydrogen bonds, leading to the formation of a three‐dimensional supramolecular network.     

Two different one‐dimensional CdII halide coordination polymers constructed through bridging carboxylate ligands

Two cadmium halide complexes, catena‐poly[[chloridocadmium(II)]‐di‐μ‐chlorido‐[chloridocadmium(II)]‐bis[μ₂‐4‐(dimethylamino)pyridin‐1‐ium‐1‐acetate]‐κ³O:O,O′;κ³O,O′:O], [CdCl₂(C₉H₁₂N₂O₂)]_n, (I), and catena‐poly[1‐cyanomethyl‐1,4‐diazoniabicyclo[2.2.2]octane [[dichloridocadmium(II)]‐μ‐oxalato‐κ⁴O¹,O²:O^1′,O^2′] monohydrate], {(C₈H₁₅N₃)[CdCl₂(C₂O₄)]·H₂O}_n, (II), were synthesized in aqueous solution. In (I), the Cd^II cation is octahedrally coordinated by three O atoms from two carboxylate groups and by one terminal and two bridging chloride ligands. Neighbouring Cd^II cations are linked together by chloride anions and bridging O atoms to form a one‐dimensional zigzag chain. Hydrogen‐bond interactions are involved in the formation of the two‐dimensional network. In (II), each Cd^II cation is octahedrally coordinated by four O atoms from two oxalic acid ligands and two terminal Cl⁻ ligands. Neighbouring Cd^II cations are linked together by oxalate groups to form a one‐dimensional anionic chain, and the water molecules and organic cations are connected to this one‐dimensional zigzag chain through hydrogen‐bond interactions.     

Bis{tris[(1H‐benzimidazol‐3‐ium‐2‐yl)methyl]amine} tetraaquaocta‐μ2‐chlorido‐octachloridopentacadmate(II) monohydrate

The title compound, (C₂₄H₂₄N₇)₂[Cd₅Cl₁₆(H₂O)₄]·H₂O, contains a [Cd₅Cl₁₆(H₂O)₄]⁶⁻ anion, two triply protonated tris[(1H‐benzimidazol‐3‐ium‐2‐yl)methyl]amine cations and one solvent water molecule. The structure of the anion is a novel chloride‐bridged pentanuclear cluster. The five unique Cd^II centres have quite different coordination environments. Two of the central hexacoordinated Cd^II cations have a CdOCl₅ chromophore, in which each Cd^II cation is ligated by four bridging chloride ligands, one terminal chloride ligand and one water molecule, adopting a distorted octahedral environment. The third central Cd^II cation is octahedrally coordinated by four bridging chloride ligands and two water molecules. Finally, the two terminal Cd^II cations are pentacoordinated by two bridging and three terminal chloride ligands and adopt a trigonal–bipyramidal geometry. A three‐dimensional supramolecular network is formed through intra‐ and intermolecular O—H...O, O—H...Cl, N—H...Cl and N—H...O hydrogen bonds and π–π interactions between the cations and anions.<!?tpb=20.6pt>     

A one‐dimensional CdII coordination polymer constructed from 4‐(dimethylamino)pyridinium‐1‐acetate ligands and thiocyanate coordination bridges

A new cadmium–thiocyanate complex, namely catena‐poly[1‐carboxymethyl‐4‐(dimethylamino)pyridinium [cadmium(II)‐tri‐μ‐thiocyanato‐κ⁴N:S;κ²S:N] [[[4‐(dimethylamino)pyridinium‐1‐acetate‐κ²O,O′]cadmium(II)]‐di‐μ‐thiocyanato‐κ²N:S;κ²S:N]], {(C₉H₁₃N₂O₂)[Cd(NCS)₃][Cd(NCS)₂(C₉H₁₂N₂O₂)]}_n, was synthesized by the reaction of 4‐(dimethylamino)pyridinium‐1‐acetate, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, two types of Cd^II atoms are observed in distorted octahedral coordination environments. One type of Cd^II atom is coordinated by two O atoms from the carboxylate group of the 4‐(dimethylamino)pyridinium‐1‐acetate ligand and by two N atoms and two S atoms from four different thiocyanate ligands, while the second type of Cd^II atom is coordinated by three N atoms and three S atoms from six different thiocyanate ligands. Neighbouring Cd^II atoms are linked by thiocyanate bridges to form a one‐dimensional zigzag chain and a one‐dimensional coordination polymer. Hydrogen‐bond interactions are involved in the formation of the supramolecular network.     

A new three‐dimensional CdII supramolecular framework constructed from the 1‐[(1H‐tetrazol‐5‐yl)methyl]‐1,4‐diazoniabicyclo[2.2.2]octane ligand

A new tetrazole–metal supramolecular compound, di‐μ‐chlorido‐bis(trichlorido{1‐[(1H‐tetrazol‐5‐yl‐κN²)methyl]‐1,4‐diazoniabicyclo[2.2.2]octane}cadmium(II)), [Cd₂(C₈H₁₆N₆)₂Cl₈], has been synthesized and structurally characterized by single‐crystal X‐ray diffraction. In the structure, each Cd^II cation is coordinated by five Cl atoms (two bridging and three terminal) and by one N atom from the 1‐[(1H‐tetrazol‐5‐yl)methyl]‐1,4‐diazoniabicyclo[2.2.2]octane ligand, adopting a slightly distorted octahedral coordination geometry. The bridging bicyclo[2.2.2]octane and chloride ligands link the Cd^II cations into one‐dimensional ribbon‐like N—H...Cl hydrogen‐bonded chains along the b axis. An extensive hydrogen‐bonding network formed by N—H...Cl and C—H...Cl hydrogen bonds, and interchain π–π stacking interactions between adjacent tetrazole rings, consolidate the crystal packing, linking the poymeric chains into a three‐dimensional supramolecular network.     

A new two‐dimensional anionic cadmium(II) polymer constructed through thiocyanate coordination bridges

A new cadmium–thiocyanate complex, poly[4‐(dimethylamino)pyridin‐1‐ium [di‐μ‐thiocyanato‐κ²N:S;κ²S:N‐thiocyanato‐κN‐cadmium(II)]], {(C₇H₁₁N₂)[Cd(NCS)₃]}_n, was synthesized by the reaction of cadmium thiocyanate and 4‐(dimethylamino)pyridine hydrochloride in aqueous solution. In the crystal structure, each Cd^II ion is square‐pyramidally coordinated by three N and two S atoms from five different thiocyanate ligands, four of which are bridging. The thiocyanate ligands play different roles in the build up of the structure; one role results in the formation of [Cd₂(NCS)₂] building blocks, while the other links the building blocks and cations via N—H...S hydrogen bonds. The N—H...S hydrogen bonds and weak π–π stacking interactions are involved in the formation of both a two‐dimensional network structure and the supramolecular network.     

A three‐dimensional cadmium(II) coordination polymer: poly[[[μ‐4,4′‐(propane‐1,3‐diyl)dipyridine‐κ2N:N](μ‐3,3′‐thiodipropionato‐κ3O,O′:O)cadmium(II)] monohydrate]

In the title coordination polymer, {[Cd(C₆H₈O₄S)(C₁₃H₁₄N₂)]·H₂O}_n, the Cd^II atom displays a distorted octahedral coordination, formed by three carboxylate O atoms and one S atom from three different 3,3′‐thiodipropionate ligands, and two N atoms from two different 4,4′‐(propane‐1,3‐diyl)dipyridine ligands. The Cd^II centres are bridged through carboxylate O atoms of 3,3′‐thiodipropionate ligands and through N atoms of 4,4′‐(propane‐1,3‐diyl)dipyridine ligands to form two different one‐dimensional chains, which intersect to form a two‐dimensional layer. These two‐dimensional layers are linked by S atoms of 3,3′‐thiodipropionate ligands from adjacent layers to form a three‐dimensional network.     

An unusual chain cadmium(II) coordination polymer: catena‐poly[[(2,2′‐bipyridyl‐κ2N,N′)cadmium(II)]‐di‐μ‐chlorido‐[(2,2′‐bipyridyl‐κ2N,N′)cadmium(II)]‐di‐μ‐thiocyanato‐κ2N:S;κ2S:N]

The title complex, [CdCl(NCS)(C₁₀H₈N₂)]_n, represents an unusual Cd^II 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 Cd^II 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 Cd^II 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.     

A novel two‐dimensional framework based on unprecedented cadmium(II) chains

The bent ligand 4‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]benzoic acid (HL) has been used to create the novel two‐dimensional coordination polymer poly[μ₂‐aqua‐μ₂‐chlorido‐{μ₂‐4‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]benzoato}cadmium(II)], [Cd(C₁₀H₈N₃O₂)Cl(H₂O)]_n, under hydrothermal reaction of HL with cadmium chloride. The crystallographically unique Cd atom is seven‐coordinated in an approximately pentagonal–bipyramidal environment of two carboxylate O atoms, two water O atoms, two Cl atoms and one triazole N atom. A notable feature is the presence of zigzag ...Cd...Cd... inorganic chains, in which neighboring Cd^II ions are doubly bridged by pairs of μ₂‐Cl atoms and μ₂‐H₂O ligands in an alternating fashion. To the authors' knowledge, this is the first example containing this bridging mode in a cadmium(II) framework. The chains are connected to one another through the bridging L⁻ ligand into a two‐dimensional undulating network. All of the two‐dimensional nets stack exactly together in an …AA… stacking sequence along the crystallographic b axis. Neighboring layers are further linked into a three‐dimensional framework via interlayer hydrogen‐bonding interactions.     

A two‐dimensional CdII coordination polymer with 2,2′‐(disulfanediyl)dibenzoate and 1,10‐phenanthroline ligands

In poly[[μ₃‐2,2′‐(disulfanediyl)dibenzoato‐κ⁵O:O,O′:O′′,O′′′](1,10‐phenanthroline‐κ²N,N′)cadmium(II)], [Cd(C₁₄H₈O₄S₂)(C₁₂H₈N₂)]_n, the asymmetric unit contains one Cd^II cation, one 2,2′‐(disulfanediyl)dibenzoate anion (denoted dtdb²⁻) and one 1,10‐phenanthroline ligand (denoted phen). Each Cd^II centre is seven‐coordinated by five O atoms of bridging/chelating carboxylate groups from three dtdb²⁻ ligands and by two N atoms from one phen ligand, forming a distorted pentagonal–bipyramidal geometry. The Cd^II cations are bridged by dtdb²⁻ anions to give a two‐dimensional (4,4) layer. The layers are stacked to generate a three‐dimensional supramolecular architecture via a combination of aromatic C—H...π and π–π interactions. The thermogravimetric and luminescence properties of this compound were also investigated.     

Bis(5‐aminotetrazole‐1‐acetato‐κO)tetraaquacobalt(II) and catena‐poly[[cadmium(II)]‐bis(μ‐5‐aminotetrazole‐1‐acetato‐κ3N4:O,O′)]

The Co^II atom in bis(5‐aminotetrazole‐1‐acetato)tetraaquacobalt(II), [Co(C₃H₄N₅O₂)₂(H₂O)₄], (I), is octahedrally coordinated by six O atoms from two 5‐aminotetrazole‐1‐acetate (atza) ligands and four water molecules. The molecule has a crystallographic centre of symmetry located at the Co^II atom. The molecules of (I) are interlinked by hydrogen‐bond interactions, forming a two‐dimensional supramolecular network structure in the ac plane. The Cd^II atom in catena‐poly[[cadmium(II)]‐bis(μ‐5‐aminotetrazole‐1‐acetato], [Cd(C₃H₄N₅O₂)₂]_n, (II), lies on a twofold axis and is coordinated by two N atoms and four O atoms from four atza ligands to form a distorted octahedral coordination environment. The Cd^II centres are connected through tridentate atza bridging ligands to form a two‐dimensional layered structure extending along the ab plane, which is further linked into a three‐dimensional structure through hydrogen‐bond interactions.     

A two‐dimensional cadmium(II) coordination polymer based on 1‐cyanomethyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane and thiocyanate ligands

A cadmium–thiocyanate complex, poly[(1‐cyanomethyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane‐κ⁴N)octakis‐μ₂‐thiocyanato‐κ⁸N:S;κ⁸S:N‐tricadmium(II)], [Cd₃(C₈H₁₄N₃)₂(NCS)₈]_n, was synthesized by the reaction of 1‐cyanomethyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane chloride, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, there are two independent types of Cd^II cation (one on a centre of inversion and one in a general position) and both are in distorted octahedral coordination environments, coordinated by N and S atoms from different ligands. Neighbouring Cd^II cations are linked together by thiocyanate bridges to form a two‐dimensional network. Hydrogen‐bonding interactions are involved in the formation of a three‐dimensional supramolecular network.     

A one‐dimensional CdII coordination polymer: catena‐poly[cadmium(II)‐bis(μ‐6‐methylpicolinato)]

In the title compound, [Cd(C₇H₆NO₂)₂]_n, the Cd^II ion has a distorted octahedral geometry. The 6‐methylpyridine‐2‐carboxylate anions are perpendicular to one another and act as bidentate and bridging ligands. Two carboxylate O atoms bridge the Cd^II ions, forming centrosymmetric dinuclear units. These units are further connected via carboxylate O atoms into a one‐dimensional polymeric chain which extends in the [100] direction.     

3‐(Pyridin‐4‐yl)acetylacetone: CdII and HgII compete for nitrogen coordination

3‐(Pyridin‐4‐yl)acetylacetone (HacacPy) acts as a pyridine‐type ligand towards Cd^II and Hg^II halides. With CdBr₂, the one‐dimensional polymer [Cd(μ‐Br)₂(HacacPy)Cd(μ‐Br)₂(HacacPy)₂]_∞ is obtained in which five‐ and six‐coordinated Cd^II cations alternate in the chain direction. Reaction of HacacPy with HgBr₂ results in [Hg(μ‐Br)Br(HacacPy)]_∞, a polymer in which each Hg^II centre is tetracoordinated. In both compounds, each metal(II) cation is N‐coordinated by at least one HacacPy ligand. Equimolar reaction between these Cd^II and Hg^II derivatives, either conducted in ethanol as solvent or via grinding in the solid state, leads to ligand redistribution and the formation of the well‐ordered bimetallic polymer catena‐poly[[bromidomercury(II)]‐μ‐bromido‐[aquabis[4‐hydroxy‐3‐(pyridin‐4‐yl)pent‐3‐en‐2‐one]cadmium(II)]‐di‐μ‐bromido], [CdHgBr₄(C₁₀H₁₁NO₂)₂(H₂O)]_n or [{HgBr}(μ‐Br){(HacacPy)₂Cd(H₂O)}(μ‐Br)₂]_∞. Hg^II and Cd^II cations alternate in the [100] direction. The HacacPy ligands do not bind to the Hg^II cations, which are tetracoordinated by three bridging and one terminal bromide ligand. The Cd^II centres adopt an only slightly distorted octahedral coordination. Three bromide ligands link them in a (2 + 1) pattern to neighbouring Hg^II atoms; two HacacPy ligands in a cis configuration, acting as N‐atom donors, and a terminal aqua ligand complete the coordination sphere. Classical O—H…Br hydrogen bonds stabilize the polymeric chain. O—H…O hydrogen bonds between aqua H atoms and the uncoordinated carbonyl group of an HacacPy ligand in a neighbouring strand in the c direction link the chains into layers in the (010) plane.     

A rare `mesh of trees' (mot) net: poly[aquahemi[μ4‐1,6‐bis(1,2,4‐triazol‐1‐yl)hexane](μ2‐5‐nitroisophthalato)cadmium(II)]

In the title coordination compound, [Cd(C₈H₃NO₆)(C₅H₈N₃)_0.5(H₂O)]_n, each Cd^II atom is six‐coordinated in a distorted octahedral environment surrounded by three carboxylate O atoms from two different 5‐nitroisophthalate (5‐NIP²⁻) ligands, two N atoms from two distinct 1,6‐bis(1,2,4‐triazol‐1‐yl)hexane (bth) ligands and one water molecule. The Cd^II centres are bridged by the bth ligands, which lie across centres of inversion, to give a honeycomb‐like two‐dimensional layer structure; the layers are further connected by the bridging 5‐NIP²⁻ ligands with a κ²;κ¹‐μ₂ coordination mode to generate the final three‐dimensional structure. Topologically, taking the the Cd^II atoms and the bth ligands as different four‐connected nodes and the 5‐NIP²⁻ ligands as linkers, the three‐dimensional structure can be simplified to a rare `mesh of trees' (mot) net with the Schäfli symbol (6⁶)(6⁴.8²)₂.     

catena‐Poly­[[chloro(1,10‐phenanthroline‐κ2N,N′)copper(II)]‐μ‐imidazolato‐κ2N:N′]

In the polymeric title compound, [Cu(im)Cl(phen)]_n, where im is the imidazolate anion (C₃H₃N₂) and phen is 1,10‐phenanthroline (C₁₂H₈N₂), each Cu^II ion is five‐coordinated by four basal N atoms (two from two different im anions and two from one phen ligand) and one axial Cl atom, in a distorted square‐pyramidal coordination geometry. Moreover, each im anion bridges two identical {CuCl(phen)}⁺ cations through its two N atoms, resulting in a one‐dimensional zigzag chain along the crystallographic a axis. In addition, pairs of adjacent chains are staggered by π–π interactions, generating a two‐dimensional layer, and neighbouring layers are further linked by two different kinds of C—H⋯Cl interactions, producing a three‐dimensional network.     

Poly[(μ5‐3‐carboxybenzene‐1,2‐dicarboxylato)lead(II)]: a helical lead(II) coordination polymer

In the title polymer, [Pb(C₉H₄O₆)]_n, the asymmetric unit contains a monomer of a Pb^II cation with a doubly deprotonated 3‐carboxybenzene‐1,2‐dicarboxylate dianion (1,2,3‐Hbtc²⁻). Each Pb^II centre is seven‐coordinated by seven O atoms of bridging carboxy/carboxylate groups from five 1,2,3‐Hbtc²⁻ ligands, forming a distorted pentagonal bipyramid. The Pb^II cations are bridged by 1,2,3‐Hbtc²⁻ anions, yielding two‐dimensional chiral layers. The layers are stacked above each other to generate a three‐dimensional supramolecular architecture via a combination of C—H...O interactions. The thermogravimetric and optical properties are also reported.     

A novel CdII coordination polymer with 1,1′‐(1,4‐butanediyl)diimidazole

The novel title Cd^II coordination polymer, poly­[[di­chlorocad­mium(II)]‐di‐μ‐1,1′‐(1,4‐butane­diyl)­di­imidazole], [CdCl₂(C₁₀H₁₄N₄)₂]_n, (I), was obtained by reaction of CdCl₂·2.5H₂O and 1,1′‐(1,4‐butane­diyl)diimidazole (hereafter L). In (I), each L molecule coordinates to two Cd^II cations through its two aromatic N atoms, thus acting as a bridging bidentate ligand. The Cd^II cations, which lie on the inversion centre, are bridged by four L molecules to form a two‐dimensional (4,4)‐network. The two‐dimensional square‐grid sheets are superimposed in an offset fashion.     

catena‐Poly[bis[1‐chloromethyl‐1,4‐diazoniabicyclo[2.2.2]octane] [cadmium(II)‐tri‐μ‐chlorido‐[chloridocadmium(II)]‐di‐μ‐chlorido‐[chloridocadmium(II)]‐tri‐μ‐chlorido] tetrahydrate]

The title compound, {(C₇H₁₅N₂Cl)₂[Cd₃Cl₁₀]·4H₂O}_n, consists of 1‐chloromethyl‐1,4‐diazoniabicyclo[2.2.2]octane dications, one‐dimensional inorganic chains of {[Cd₃Cl₁₀]⁴⁻} anions and uncoordinated water molecules. Each of the two independent Cd^II ions, one with site symmetry 2/m and the other with site symmetry m, is octahedrally coordinated by chloride ions (two with site symmetry m and one with site symmetry 2), giving rise to novel polymeric zigzag chains of corner‐sharing Cd‐centred octahedra parallel to the c axis. The organic cations, bisected by mirror planes that contain the two N atoms, three methylene C atoms and the Cl atom, are ordered. Hydrogen bonds (O—H...Cl and O—H...O) between the water molecules (both with O atoms in a mirror plane) and the chloride anions of neighbouring chloridocadmate chains form a three‐dimensional supramolecular network.     

A two‐dimensional cadmium(II) polymer based on nicotinic acid and thiocyanate ligands

A cadmium–thiocyanate complex, poly[[bis(nicotinic acid‐κN)di‐μ‐thiocyanato‐κ²N:S;κ²S:N‐cadmium(II)] monohydrate], {[Cd(NCS)₂(C₆H₅NO₂)₂]·H₂O}_n, was synthesized by the reaction of nicotinic acid, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, each Cd^II cation is in a distorted octahedral coordination environment, coordinated by the N and S atoms of nicotinic acid and thiocyanate ligands. Neighbouring Cd^II cations are linked together by thiocyanate bridges to form a two‐dimensional network. Hydrogen‐bond interactions between the uncoordinated solvent water molecules and the organic ligands result in the formation of the three‐dimensional supramolecular network.