A three‐dimensional framework of bis­[tris­(ethyl­enediamine)zinc] tetra­iodo­cadmate diiodide assisted by N—H⋯I hydrogen bonds

The title salt, [Zn(C₂N₂H₈)₃]₂[CdI₄]I₂, conventionally abbreviated [Zn(en)₃]₂[CdI₄]I₂, where en is ethyl­enediamine, contains discrete [Zn(en)₃]²⁺ cations and [CdI₄]²⁻ anions with distorted octa­hedral and nearly tetra­hedral geometries, respectively, as well as uncoordinated I⁻ ions. The cation and the free I⁻ anion lie on twofold rotation axes and the [CdI₄]²⁻ anion lies on a axis in the space group I2d. The structure exhibits numerous weak inter‐ionic hydrogen bonds of two types, viz. N—H⋯I⁻(free ion) and N—H⋯I([CdI₄]²⁻), which support the resulting three‐dimensional framework.     

Cadmium(II) iodide molecular coordination compounds with 4-methylpyridine and 4-methylquinoline

The coordination compounds [CdI₂(4-MePy)₂] (I) and [CdI₂(4-MeQuin)₂] (II) where Quin is quinoline have been synthesized, and their structure has been solved. Crystals of complex I are monoclinic, space group C2/c, a = 13.353(1) Å, b = 16.653(1) Å, c = 14.380 (1) Å, β = 103.17(1)°, V = 3113.5(4) ų, ρ_calcd = 2.425 g/cm³, Z = 8. Crystals of complex II are monoclinic, space group P2₁/c, a = 10.647(1) Å, b = 25.264(1) Å, c = 8.610(1) Å, β = 113.73(1)°, V = 2120.1(3) ų, ρ_calcd = 2.044 g/cm³, Z = 4. Polymer [CdI₂(4-MePy)₂]_∞ chains running in the direction [001] are formed in the structure of complex I. Each of the two crystallographically nonequivalent Cd(1) and Cd(2) atoms are octahedrally surrounded by the four iodine and two nitrogen atoms of the 4-MePy ligand. The Cd(1)?Cd(2) distance in a chain is 4.33 Å. The structure of complex II is built of [CdI₂(4-MeQuin)₂] discrete neutral clusters. The two iodine and two nitrogen atoms of the 4-MeQuin ligand participate in the coordination of the Cd²⁺ ion. The cadmium coordination polyhedron is a distorted tetrahedron (Cd-I_avg, 2.72 Å; Cd-N_avg, 2.30 Å; angles N(I)CdN(I), 98.3–121.8°). The minimum and maximum values correspond to the ICdI angle and NCdN angle, respectively. Complex I is photoluminescent in the solid state at room temperature.     

A complex of cadmium(II) iodide with 4-cyanopyridine: Synthesis,crystal structure,and luminescent properties

The complex [CdI₂(4-CNPy)₂] (I) was obtained by a reaction of CdI₂ with 4-cyanopyridine (4-CNPy, C₆H₄N₂) and structurally characterized (CIF file CCDC no. 983377). The crystals of complex I are monoclinic, space group C2, a = 24.698(5) Å, b = 4.127(1) Å, c = 7.597(2) Å, β = 96.05(1)°, V = 770.0(3) ų, ρ_calcd = 2.477 g/cm³, Z = 2. In structure I, iodine atoms serve to unite complex molecules into the polymer chains [CdI₂(4-CNPy)₂]_∞ along the direction [010]. The Cd(1) atom lying on a twofold axis has a slightly distorted octahedral environment made up of four bridging iodine atoms and two nitrogen atoms of two ligands 4-CNPy (Cd-I_av, 2.947(2) and Cd-N(1), 2.410(6) Å). Within each chain, cadmium atoms are spaced apart at 4.13 Å. Complex I exhibits photoluminescence.     

Confirming the Molecular Basis of the Solvent Extraction of Cadmium(II) Using 2-Pyridyl Oximes through a Synthetic Inorganic Chemistry Approach and a Proposal for More Efficient Extractants

The present work describes the reactions of CdI₂ with 2-pyridyl aldoxime (2paoH), 3-pyridyl aldoxime (3paoH), 4-pyridyl aldoxime (4paoH), 2-6-diacetylpyridine dioxime (dapdoH₂) and 2,6-pyridyl diamidoxime (LH₄). The primary goal was to contribute to understanding the molecular basis of the very good liquid extraction ability of 2-pyridyl ketoximes with long aliphatic chains towards toxic Cd(II) and the inability of their 4-pyridyl isomers for this extraction. Our systematic investigation provided access to coordination complexes [CdI₂(2paoH)₂] (1), {[CdI₂(3paoH)₂]}_n (2), {[CdI₂(4paoH)₂]}_n (3) and [CdI₂(dapdoH₂)] (4). The reaction of CdI₂ and LH₄ in EtOH resulted in a Cd(II)-involving reaction of the bis(amidoxime) and isolation of [CdI₂(L’H₂)] (5), where L’H₂ is the new ligand 2,6-bis(ethoxy)pyridine diimine. A mechanism of this transformation has been proposed. The structures of 1, 2, 3, 4·2EtOH and 5 were determined by single-crystal X-ray crystallography. The complexes have been characterized by FT-IR and FT-Raman spectra in the solid state and the data are discussed in terms of structural features. The stability of the complexes in DMSO was investigated by ¹H NMR spectroscopy. Our studies confirm that the excellent extraction ability of 2-pyridyl ketoximes is due to the chelating nature of the extractants leading to thermodynamically stable Cd(II) complexes. The monodentate coordination of 4-pyridyl ketoximes (as confirmed in our model complexes with 4paoH and 3paoH) seems to be responsible for their poor performance as extractants.     

Revealing the structural chemistry of the group 12 halide coordination compounds with 2,2′-bipyridine and 1,10-phenanthroline

The coordination compounds of group 12 halides with 2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen), 2[CdF₂(bpy)₂]·7H₂O (1), [ZnI(bpy)₂]⁺·I₃^? (2), [CdI₂(bpy)₂] (3), [Cd(SiF₆)H₂O(phen)₂]·[Cd(H₂O)₂(phen)₂]²⁺·F^–·0.5(SiF₆)^2–·9H₂O (4), [Hg(phen)₃]²⁺·(SiF₆)^2–·5H₂O (5), [ZnBr₂(phen)₂] (6), 6[Zn(phen)₃]²⁺·12Br^–·26H₂O (7) and [ZnI(phen)₂]⁺·I^– (8), have been synthesized and characterized by X-ray crystallography, IR spectroscopy, elemental and thermal analysis. Structural investigations revealed that metal?:?ligand stoichiometry in the inner coordination sphere is 1?:?2 or 1?:?3. A diversity of intra- and intermolecular interactions exists in structures of 1–8, including the rare halogen?halogen and halogen?π interactions. The thermal and spectroscopic properties were correlated with the molecular structures of 1–8. Structural review of all currently known coordination compounds of group 12 halides with bpy and phen is presented.     

Ruthenium(II/III)‐Based Compounds with Encouraging Antiproliferative Activity against Non‐small‐Cell Lung Cancer

Hereby we present the synthesis of several ruthenium(II) and ruthenium(III) dithiocarbamato complexes. Proceeding from the Na[trans‐Ru^III(dmso)₂Cl₄] ( 2 ) and cis‐[Ru^II(dmso)₄Cl₂] ( 3 ) precursors, the diamagnetic, mixed‐ligand [Ru^IIL₂(dmso)₂] complexes 4 and 5 , the paramagnetic, neutral [Ru^IIIL₃] monomers 6 and 7 , the antiferromagnetically coupled ionic α‐[Ru^III₂L₅]Cl complexes 8 and 9 as well as the β‐[Ru^III₂L₅]Cl dinuclear species 10 and 11 (L=dimethyl‐ (DMDT) and pyrrolidinedithiocarbamate (PDT)) were obtained. All the compounds were fully characterised by elemental analysis as well as ¹H NMR and FTIR spectroscopy. Moreover, for the first time the crystal structures of the dinuclear β‐[Ru^III₂(dmdt)₅]BF₄ ? CHCl₃ ? CH₃CN and of the novel [Ru^IIL₂(dmso)₂] complexes were also determined and discussed. For both the mono‐ and dinuclear Ru^II and Ru^III complexes the central metal atoms assume a distorted octahedral geometry. Furthermore, in vitro cytotoxicity of the complexes has been evaluated on non‐small‐cell lung cancer (NSCLC) NCI‐H1975 cells. All the mono‐ and dinuclear Ru^III dithiocarbamato compounds (i.e., complexes 6 – 10 ) show interesting cytotoxic activity, up to one order of magnitude higher with respect to cisplatin. Otherwise, no significant antiproliferative effect for either the precursors 2 and 3 or the Ru^II complexes 4 and 5 has been observed.     

Coordination molecular compounds of cadmium(II) iodide with dimethylpyridines

The reactions of CdI₂ with dimethylpyridines (Me₂Py is C₇H₉N) afford complexes CdI₂(2,3-Me₂Py)₂] (I), [CdI₂(2,6-Me₂Py) (II), and CdI₂(3,5-Me₂Py)₂ (III). The structures of compounds I and II are determined. The crystals of complex I are orthorhombic, space group Pbca, a = 7.930(1) Å, b = 15.537(1) Å, c = 29.943(1) Å, V = 3689.1(5) ų, ρ_calcd = 2.090 g/cm³, Z = 8. The crystals of complex II are monoclinic, space group C2/c, a = 14.784(1), b = 11.991(1), c = 17.711(1) Å, β = 90.39(1)°, V = 1081.1(2) ų, ρ_calcd = 2.908 g/cm³, Z = 4. The structure of compound I is built of discrete neutral complexes [CdI₂(2,3-Me₂Py)₂]. The Cd polyhedron is a distorted tetrahedron (Cd-I 2.289–2.295, Cd-N 2.708–2.734 Å, angles N(I)CdN(I) 103.1°-114.8°). Polymer chains [CdI₂(2,6-Me₂Py)]_∞ extended along the direction [100] are observed due to the bridging iodine atoms in structure II. The Cd polyhedron is a trigonal bipyramid containing iodine atoms at the axial vertices (Cd-I_aks 3.040 Å) and two iodine atoms and the nitrogen atom of the Me₂Py ligand in the equatorial plane Me₂Py (Cd-I_eq 2.840 Å, Cd-N 2.309 Å). The compounds in the solid state are photoluminescent.     

New cadmium(II) halides modified by N-heterocyclic molecules

Under the solvothermal condition, the reaction of CdI₂, bpp and KI at pH = 8 afforded compound [CdI₂(bpp)] (bpp = 1,2-bis(4-pyridyl)propane) 1, while at the ambient conditions, the reactions of CdX₂, dabco and KX at pH = 4–5 produced compounds [H₂(dabco)][CdBr₄]·H₂O (dabco = 1,4-diazabicyclo[2,2,2]octane) 2 and [(Hdabco)CdI₃] 3. X-ray single-crystal diffraction analysis reveals that (i) compound 1 possesses a one-dimensional (1-D) zigzag chain structure. The large volume bpp molecule controls the Cd²⁺ ion to adopt a tetrahedral geometric configuration; (ii) both compounds 2 and 3 are mononuclear. Interestingly, in the same pH environments, dabco was in situ diprotonated in compound 2, while dabco was in situ monoprotonated in compound 3. The templating effect as well as the X⁻ ion maybe plays a key role in the protonated degree for dabco in an acidic environment. The photoluminescence analysis indicates that compound 1 emits the strong green light, which should be attributed to a combination of two types of charge transfers: the charge transfer between Cd²⁺ and I⁻; the charge transfer between Cd²⁺ and bpp.     

Solubility of <Emphasis Type="Italic">d</Emphasis>-Element Salts in Organic and Aqueous–Organic Solvents: VI.<Superscript>1</Superscript> Structure and Thermal Stability of Cadmium Iodide and Bromide Solvates with Dimethylacetamide and Dimethylformamide

Five solvates, [CdBr₂(DMF)] _n , [CdBr₂(DMA)] _n , [CdI²(DMF)] ⁿ , [Cd(DMF)₆][Cd₂I₆], and {[Cd(DMA)₆][Cd₅I₁₂] _n } _m , were isolated from the ternary systems CdX₂–L–H₂O (X = Br, I; L = N,N-dimethylacetamide, N,N-dimethylformamide) and characterized by the X-ray single crystal analysis. The structures of the first three solvates is similar to each other in structures and represent a one-dimensional polymer chain, the fourth solvate has the discrete structure containing [Cd(DMF)₆]²⁺ and [Cd₂I₆]^2– ions, and the fifth solvate contains discrete [Cd(DMA)₆]²⁺ cations and the polymer anionic fragment [Cd₅I₁₂] _n ^2n–.     

Coordination geometries and crystal structures of cadmium(II) complexes with a new amino alcohol (NN′O) ligand

The new ligand 2-(2-(2-hydroxyethylamino)ethylamino)cyclohexanol, (HEAC), was prepared under microwave conditions through ring opening of cyclohexene oxide with 2-(2-amino-ethylamino)ethanol. Its cadmium(II) complexes [Cd₂(HEAC)₂(μ-Cl)₂Cl₂] (1) and [Cd(HEAC)₂][CdI₄] (2) were identified by elemental analysis, FT-IR, Raman, ¹H NMR spectroscopies, and single-crystal X-ray diffraction. HEAC formed 1?:?1 M?:?L complexes with cadmium chloride and cadmium iodide. Complex 1 crystallized as a dimer with two asymmetrically bound bridging Cl^? and a terminally coordinated Cl^? on each metal. The geometry around the cadmiums in 1 with four five-membered chelate rings and four Cl^? ligands is distorted octahedral for each Cd(II). The cyclohexanol OH of each ligand forms intramolecular hydrogen bonds. In 2, the coordination numbers for cadmium in [Cd(HEAC)₂]²⁺ and [CdI₄]^2? moieties are six and four, respectively. In [Cd(HEAC)₂]²⁺ each ligand coordinates through two N- and one O-donors, leading to a distorted octahedral geometry. The geometry of [CdI₄]^2? in 2 is slightly distorted tetrahedral. The protonation equilibrium constants of the two secondary amino groups in HEAC, determined by pH-potentiometry, were 6.26 and 9.26, respectively, at 25°C. Stability constants for this ligand with Ni(II), Cu(II), and Zn(II) (1?:?1 M?:?L), determined by glass-electrode potentiometry, were 7.13, 10.50, and 5.42, respectively.     

Synthetic procedures and structural features of new di- and tri-nuclear chelate compounds of Cd(II) with sulfur and nitrogen donor ligands

Cd(dmpymt)₂ reacts with CdCl₂, CdBr₂·4H₂O, CdI₂, 2,2′-bipyridine and 1,10-phenanthroline to give the dimeric chelates [Cd(dmpymt)(bpy)Cl]₂ and [Cd(dmpymt)(phen)Cl]₂, as well as the tri-nuclear complexes [Cd₃(dmpymt)₄(bpy)₂Br₂] and [Cd₃(dmpymt)₄(bpy)₂I₂] (dmpymtH = 4,6-dimethylpyrimidine-2-thione; bpy = 2,2′-bipyridine; phen = 1,10-phenantroline). In all complexes the Cd(II) centers present the coordination number six. The new compounds are examples of the managing of the final aggregation state of thiolate metal complexes by introducing co-ligands to block specific coordination sites of the metal center.     

The Tetrachloridoaurates(III) of Zinc(II) and Cadmium(II)

The first salt‐like compounds of dications with [AuCl₄]^– anions are reported. The compounds Zn[AuCl₄]₂ · (AuCl₃)_1.115 ( 1 ) and Cd[AuCl₄]₂ ( 2 ) are obtained from reactions of MCl₂ (M = Zn, Cd) and elemental gold in liquid chlorine at ambient temperature under autogenous pressure and subsequent annealing at 230 °C. The structure of 1 represents an incommensurately modulated composite [superspace group C2/c(α0γ)0s] built of two subsystems. The first subsystem contains chains of zinc(II) tetrachloridoaurate(III), which feature a slightly distorted octahedral coordination of Zn and can be described by the Niggli formula ¹_∞{Zn[AuCl₄]_1/1[AuCl₄]_2/2}. The second subsystem consists of Au₂Cl₆ molecules, which are located in channels built up by the first subsystem. The structural parameters of the hosted Au₂Cl₆ molecules show only small deviations from neat AuCl₃. The crystal structure of Cd[AuCl₄]₂ ( 2 ) consists of chains built of Cd²⁺ ions coordinated by bridging [AuCl₄]^– anions and alternating Cd‐Au sequence. Cd has a distorted octahedral coordination environment.     

Assembly of two new polyoxometalate-templated supramolecular compounds by utilizing flexible 1,4-bis(pyrazol-1-ylmethyl)benzene ligand

Two new polyoxometalate-templated supramolecular compounds, [Cu^I₄(bpmb)₄][PMo^VI₁₁Mo^VO₄₀] (1) and [Cu^I₄(bpmb)₄SiW₁₂O₄₀] (2) (bpmb = 1,4-bis(pyrazol-1-ylmethyl)benzene), have been synthesized under hydrothermal conditions and characterized by routine methods. Structural analysis shows that in 1, there exist crown-like [Cu^I₄(bpmb)₄] coordination macrocycles, and the Keggin polyanions [PMo ^VI₁₁Mo^VO₄₀]^4? (abbr. as PMo₁₂), which direct the crown-like macrocycle to form a 3-D supramolecular framework. In 2, there exist unusual meso-helix chains, and these chains are mutually interlaced in a wave–trough pattern, but without intersection resulting in a multi-cavity layer, in which the [SiW₁₂O₄₀]^4? (abbr. as SiW₁₂) clusters as guest molecules occupy the cavities of the layers. The distinct structural features of the two compounds suggest that Keggin polyanions should play a significant role in the process of assembly. Electrocatalytic properties of 1 and 2 were investigated.     

A Series of Iodoargentates Directed by Solvated Metal Cations Featuring Uptake and Photocatalytic Degradation of Organic Dye Pollutants

By using solvated metal cations as structure‐directing agents, three new iodoargentates, namely, [Fe(DMSO)₆][Ag₆I₉]?DMSO ( 1 ), [Fe(H₂O)₆][Ag₁₅I₁₈] ( 2 ) and [Cd(DMSO)₆][Ag₈I₁₀] ( 3 ) (DMSO=dimethyl sulfoxide) have been solvothermally prepared and structurally characterized. The structures of compounds 1 and 2 can be described as 1D chains constructed from the linkage of [Ag₆I₉] and [Ag₅I₁₁] building units, respectively. For compound 3 , the [Ag₁₀I₂₂] building blocks are directly interconnected to form a 2D [Ag₈I₁₀] layer, which are further interconnected via intermolecular forces to generate a 3D supramolecular framework with 1D large channels occupied by [Cd(DMSO)₆]²⁺ cations. Interestingly, compounds 1 – 3 exhibit an ion‐exchange behavior for the adsorption of a specific dye (methylene blue, MB). Moreover, photocatalytic experiments indicate that these iodoargentates can be considered as promising photocatalysts for the degradation of organic dye pollutants.     

Syntheses,structures, and properties of two binuclear cadmium(II) iodides containing a bis(tridentate) Schiff base/tetradentate tripodal amine: control of coordination numbers by varying ligand matrices

Two binuclear cadmium(II) iodide compounds of the types [Cd₂(L1)(I)₄] (1) and [(L2)Cd(μ-I)CdI₃] (2) [L1 = N,N′-(bis(pyridine-2-yl)formylidene)triethylenetetramine and L2 = tris(2-aminoethyl)amine] are synthesized and characterized. X-ray structural study shows that each cadmium(II) in 1 has a distorted square pyramidal geometry with a CdN₃I₂ chromophore and that L1 behaves as a binucleating bis(tridentate) ligand bridging the metal centers with iodides remaining as terminals. In 2, one cadmium(II) adopts a distorted tetrahedral geometry with a CdI₄ chromophore surrounded by four iodides, while the other has a distorted trigonal bipyramidal environment with CdN₄I chromophore bound by four N atoms of L2 and one bridging iodide. Weak C–H···π interactions in 1 result in an infinite 1D chain; however, such weak non-covalent interactions are absent in 2. The Schiff base complex, 1, shows high-energy intraligand ¹(π–π*) fluorescence in DMF solution at room temperature, whereas compound 2 containing tripodal amine is fluorescent-inactive.     

Untersuchungen an Polyhalogeniden III. Tetrammin-kupfer(II)-tetraiodid, [Cu(NH3)4I2 · I2], und Tetrammin-kupfer(II)-hexaiodid, [Cu(NH3)4I3]I3

Studies on Polyhalides. III. Crystal Structures of [Cu(NH₃)₄I₂ · I₂] and [Cu(NH₃)₄I₃]I₃ Tetramminecopper(II)tetraiodide [Cu(NH₃)₄I₂ · I₂] (I) crystallizes monoclinically in the space group C2/m with a = 1 185.9 pm, b = 892.8 pm, c = 656.8 pm, β = 111.10° and Z = 2 formula units. Tetramminecopper(II)hexaiodide [Cu(NH₃)₄I₃]I₃ (II) crystallizes orthorhombically in the space group Pnnm with a = 874.9 pm, b = 1 089.8 pm, c = 885.3 pm, and Z = 2 formula units. A special feature of these structures are coordinated polyiodide ions I₄^2? (I) or I₃^? (II). In both compounds four coplanar nitrogen atoms and two axial iodine atoms form a quasi-octahedral coordination around copper with the usual (4+2)-tetragonal distortion. The copper ions are connected by linear, centrosymmetric polyiodide ions I₄^2? (I) or I₃^? (II). Therefore infinite planar zigzag chains of units [Cu(NH₃)₄I₄] (I) or [Cu(NH₃)₄I₃]⁺(II) are resulting. The counterion I₃^? (II) is intercalated between these chains.     

Using experimental methods and CSD data for investigating the products of the reaction between 2-((2-aminoethyl)amino)ethanol with CdI2 and CdI2/HgI2-mixtures

The binding modes of 2-((2-aminoethyl)amino)ethanol-based ligands were explored using the Cambridge Structural Database (CSD). To extend this field, a new cadmium complex containing 2-((2-aminoethyl)amino)ethanol (AEAE), [Cd(AEAE)₂][Cd(AEAE)₂]′[CdI₄]₂ (1), was prepared and characterized by spectroscopic methods and single-crystal X-ray diffraction. The reaction of AEAE with a 1:1 mixture of CdI₂ and HgI₂ was also investigated. The complex, [Cd(AEAE)₂][I₂Hg(μ-I₂)₂HgI₂] (2), was synthesized and characterized. Compounds 1 and 2 represent the first tridentate binding modes of an AEAE type ligand with Cd²⁺. Geometrical investigation for complexes containing Cd(N^amine₂O^alcohol)₂, CdI_n, and HgI_n environment were carried out using the CSD software. Also different possible diastereomers which can be formed in coordination of a pair of tridentate AEAE ligands in octahedral geometry were studied and discussed.     

Synthesis and structures of copper(II) and cadmium(II) compounds based on pyridazine derivative ligands

The two new compounds [Cu(HODA)₂(H₂O)₂] · 3H₂O (I) and [Cd(HODA)₂(H₂O)₃] (II) (HODA = 6-oxo-1,6-dihydropyridazine-4-carboxylic acid) based on pyridazine derivation ligands have been synthesized and characterized by elemental analysis, infrared spectrum and X-ray single crystal diffraction. X-ray analysis shows that in compound I, Cu²⁺ ion is four-coordinated with a plane square geometry while Cu²⁺ ion in compound II is seven-coordinated with a distorted pentagonal bipyramid geometry. Both of the two units are all connected as 3D supramolecular structures by the intermolecular hydrogen bonds. Moreover, thermal gravimetric analysis of two compounds has been also investigated.     

Investigation of Metastable Low Dimensional Halometallates

The solvothermal synthesis, structure determination and optical characterization of five new metastable halometallate compounds, [1,10-phenH][Pb_3.5I₈] (1), [1,10-phenH₂][Pb₅I₁₂]·(H₂O) (2), [1,10-phen][Pb₂I₄] (3), [1,10-phen]₂[Pb₅Br₁₀] (4) and [1,10-phenH][SbI₄]·(H₂O) (5), are reported. The materials exhibit rich structural diversity and exhibit structural dimensionalities that include 1D chains, 2D sheets and 3D frameworks. The optical spectra of these materials are consistent with bandgaps ranging from 2.70 to 3.44 eV. We show that the optical behavior depends on the structural dimensionality of the reported materials, which are potential candidates for semiconductor applications.     

Polyoxometalates–Directed Assembly of Inorganic–Organic Hybrid Compounds with Copper Multinuclear Nano-cluster Based on Flexible Double Tetrazole-based Thioether

Two new inorganic–organic hybrid compounds constructed from different polyoxometalates (POMs) and copper multinuclear clusters, [Cu(bmte)(H₂Mo₈O₂₆)_0.5]·3H₂O (1) and [Cu₃(bmte)₃(HSiMo₁₂O₄₀)]·H₂O (2) (bmte = 1,2-bis(1-methyl-5-mercapto-1,2,3,4-tetrazole)ethane), have been synthesized under hydrothermal conditions with a flexible double tetrazole-based thioether and characterized by IR, TG and single-crystal X-ray diffraction analyses. In compound 1, two bmte ligands chelate two Cu^I ions with three N atoms to form a binuclear nano-scale subunit [Cu₂(bmte)₂]²⁺, then the binuclear Cu^I subunits are connected by [Mo₈O₂₆]⁴⁻ anions to build a one dimensional (1D) chain. In compound 2, a trinuclear nano-scale subunit [Cu₃(bmte)₃]³⁺ constructed from three Cu^I ions and three bmte ligands has been obtained, and the adjacent trinuclear subunits are linked by [SiMo₁₂O₄₀]⁴⁻ anions to form a “zipper” 1D chain. The adjacent chains of the title compounds are ultimately extended into 2D layers by hydrogen bonds between bmte and POMs. The structural difference of the two compounds indicates that the POMs play an important structure-directed role on the final networks. In addition, the electrochemical behavior of 2-modified carbon paste electrode (2-CPE) and its electrocatalytic reduction of nitrite have been discussed.