Syntheses and Characterizations of the Lanthanide Compounds with 4-(4-Pyridyl)benzoate and 2,6-Pyridinedicarboxylate as Ligands

Two new lanthanide coordination polymers, namely [Ln_2(μ_3-OH)(pydca)-(pyba)3(H_2O)]n(Ln = Pr, 1; Eu, 2; Hpyba = 4-(4-pyridyl)benzoic acid; H2 pydca = 2,6-pyridinedicarboxylic acid), have been hydrothermally synthesized and characterized by IR spectroscopy and X-ray single-crystal diffraction. The chains of 1 and 2 are constructed by tetrametallic units of [Ln_4(OH)_2(pyba)_2], which are further linked by μ_4-k_1N, k_1O, k_2O′, k_2O″-pydca and μ_2-k_1N, k_1O, k_1O′-pyba to form 2D frameworks. Luminescence measurement reveals that compound 2 exhibits strong reddish emission at room temperature.     

A CLUSTER COMPOUND WITH DI-ENDOXYGEN LIGANDS——THE CRYSTAL AND MOLECULAR STRUCTURE OF [Fe(MOS_4O)_2][N(C_2H_5)_4]3

[Fe(MoS_4O)_2] [N(C_2H_3)_4]_3 cluster compound with di-end-oxygen ligands has been prepared and characterized by the X-ray diffraction method. The compound crystallizes in a monoclinic space group P2_1/n with lattice parameters a=13.019(4), b=16.959(5), c=18.234(5), β=97.34(2)(°), Z=4. The final agreement factors are R=0.0740, Rw=0.0598. The terminal bond length, Mo-S_t and bridged one, MO-S_b for the compound are much longer than the counterpart without end-oxygen ligand. It possibly suggests that low valence of molybdenum and smaller electronegativity of sulphur than oxygen lead to the charge transfer as S→Mo→O.     

Synthesis,Crystal Structure and Photoluminescent Property of a Novel Dy~(3+) Coordination Compound Containing Rare(H_2O)_(22) Clusters

A novel Dy~(3+) coordination compound,(H_2pipz)(H_3O)[Dy(pydc)_3]·11H_2O(1,pipz = piperazine and H_2pydc = pyridine-2,6-dicarboxylic acid),has been hydrothermally synthesized and characterized by X-ray single-crystal diffraction,elemental analysis. It is interesting that the packing structure of compound 1 contains 22-core water clusters. Compound 1 is extended into a threedimensional supramolecular structure via O···H···O hydrogen bonding interactions. Furthermore,the luminescent property of compound 1 was also investigated.     

Crystal Structure,Electrochemical and Fluorescent Properties of a New Copper(Ⅱ) Coordination Polymer with 2,3-Pyridinedi-carboxylic Acid

A new copper(Ⅱ) coordination polymer [Cu_5(Hpt)_5(H_2O)_2(2,3-PCA)2]n·12 nH_2O(1) has been successfully synthesized under hydrothermal conditions with copper hydroxide, 3-(pyridin-2-yl)-1,2,4-triazole(Hpt) and 2,3-pyridinedi-carboxylic acid(2,3-PCA). The structure of the title compound was determined by X-ray diffraction analyses, elemental analyses and IR spectrum. The architecture of 1 consists of one-dimensional sandwich-like chains which are connected by extensive hydrogen bonding interactions. The solid-state photoluminescence displays an obvious emission band at 384 nm upon excitation at 340 nm. In addition, electrochemistry property has also been studied.     

A Novel 3-D Zn(Ⅱ) Coordination Polymer for Inhibiting the Human Osteosarcoma Cells Growth

A new three-dimensional Zn(II) coordination polymer, namely [Zn_4(bpydb)_3(tz)2(H_2O)_2]n(1), has been synthesized by the self-assembly reactions of Zn(NO_3)_2·6H_2O, bpydb H_2, Htz and DMF. Single-crystal X-ray structural analysis reveals that compound 1 features a three-dimensional framework structure and is the first example of Zn-containing coordination polymers based on two kinds of ligands bpydb H_2 and Htz. It crystallizes in triclinic, space group P1 with a = 14.9953(12), b = 17.5335(17), c = 20.2381(11) ?, α = 115.225(7), β = 92.329(5), γ = 105.606(8)o, V = 4561.9(7) ?3, Z = 2, F(000) = 1644, Dc = 1.177 Mg/m3, Mr = 1616.76 and μ = 1.098 mm-1. The antitumor activities of compound 1 and its corresponding organic ligands(bpydb H_2 and Htz) were investigated for inhibiting human osteosarcoma cells(MG-63 and U-2 OS) growth by MTT assay. It was found that compared with the two ligands, compound 1 exerted rather potent activities against all of these cell lines.     

Mixed-solvothermal Synthesis,Crystal Structure and Luminescence of a New Dinuclear Yttrium(Ⅲ) Coordination Polymer with 1-D Wave-like Infinite Chains

A new dinuclear Y~(3+) coordination polymer{[Y_2(H_2O)_2(C_(14)H_8O_4)_3(C_(12)H_8N_2)_2]·3 H_2O}_n (1, C_(14)H_8 O_4 = 2,2?-biphenyldicarboxylate, phen = 1,10-phenanthroline), has been obtained by means of a mixed-solvothermal method using ethylene glycol and water as solvent. The compound was characterized by elemental analysis, energy-dispersive X-ray spectroscopy(EDS), IR spectrum and single-crystal X-ray diffraction. The results reveal that 1 belongs to monoclinic system, space group C2/c with a = 24.249(3), b = 12.069(48), c = 22.7304(08) ?, β = 113.480(7)°, Z = 4, V = 6102(2) ?~3, Dc = 1.462 g·cm~(-3), F(000) = 2728, μ = 1.968 mm~(-1), the final R = 0.0673, w R = 0.1508 and S = 1.085. Its structure can be regarded as a 1-D coordination polymer constructed by Y~(3+) cations, 2,2?-biphenyldicarboxylate, 1,10-phenanthroline and water molecules. The compound not only contains two kinds of organic ligands, but also exhibits interesting wave-like infinite chains and 18-MR windows with the diameter of 4.070(7)? × 5.326(9)?. The structure is further stabilized by means of O–H···O hydrogen bonds and π-π stacking interactions. Furthermore, the luminescent properties(including emission spectrum, CIE chromaticity coordinate and decay curve) of 1 were also investigated in the solid-state at room temperature.     

Synthesis, Crystal Structure and Photoluminescence of a 2D Two-fold Interpenetrating Cd(Ⅱ) Coordination Polymer Based on a Flexible Reduced Schiff Base Ligand

<正>By the reaction of cadmium chloride with a reduced Schiff base ligand (H_2L = N-(4- carboxybenzyl)-glycine), a novel Cd(II) compound [Cd(HL)_2]·4H_2O (1) has been obtained. Single-crystal X-ray diffraction analysis reveals that it crystallizes in orthorhombic, space group Pbcn with a = 13.9788(8), b = 24.4204(14), c = 13.9580(8), V = 4764.8(5)~3, Z = 8, M_r = 600.84, D_c = 1.675 g/cm~3, μ = 0.983 mm~(-1), F(000) = 2448, S = 1.084, R = 0.0806 and wR = 0.1705 (I > 2σ(I)). It displays a 2D two-fold interpenetrating structure. The Cd(II) ions are six-coordinated. The cross-linkage of Cd(II) ions by the bridge of HL anions results in a [Cd(HL)_2] layer. Every two [Cd(HL)_2]_n layers are penetrated with each other, resulting in a two-fold interpenetrating double-layer structure by π-π stacking interactions and hydrogen bonds. Such double-layers are further linked by hydrogen bonds into a supramolecular structure. Photoluminescent investigation shows that compound 1 displays strong emission in the purple region.     

A New Cobalt(Ⅱ)Polymer Based on 1-Butylben-zimidazole and Terephthalate Mixed-ligands:Crystal Structure and Weak Interactions

<正>A new cobalt(Ⅱ)polymer with quasi-rectangular cavities,[Co(L)_2(TP)·H_2O]_n 1(L =1-butylbenzimidazole,TP=terephthalate ion)has been prepared by means of self-assembly of 1-butylbenzimidazole,terephthalic acid and Co(NO_3)_2·6H_2O.The structure of 1 was characterized by X-ray diffraction analysis.In the crystal packing,2-D supramolecular layers are formed viaπ-πstacking interactions.The fluorescence emission spectra of L and 1 are described.     

An Efficient Novel Synthesis of 14-O-[(4-Amino-6-hydroxy-pyrimidine-2-yl)thioacetyl] Mutilin and the Antibacterial Evaluation

The title structure of 14-O-[(4-amino-6-hydroxy-pyrimidine-2-yl)thioacetyl] mutilin, C_(26)H_(47)N_3O_5S, has been synthesized using 22-O-tosyl pleuromutilin and 4-amine-6-hydroxy-2-mercatopyrimidine monohydrate, and its structure was characterized by IR, NMR, H RMS and single-crystal X-ray diffraction. This compound has a 5-6-8 tricyclic carbon skeleton and a pyrimidine ring. It crystallizes in orthorhombic, space group P2_12_12_1 with a = 10.494(3), b = 16.997(5), c = 16.997 ?, Z = 4, D_c = 1.275 Mg×m~(–3), μ = 0.220 mm~(–1), F(000) = 1248, wR(F~2) = 0.1159 and R = 0.0381. The preliminary biological test showed that the title compound has more potent inhibitions to Staphylococcus aureus, MRSA and MRSE than that of tiamulin fumarate in vitro.     

THE SYNTHESIS AND CRYSTAL STRUCTURE OF CIS-BIS(1,10-PHENANTHROLINE)GLYCINECOBALT(Ⅲ)

A new coordination compound of cis-bis(1,10-phenanthroline)glycinecobalt(Ⅲ)chloridate tetrahydrate,cis-[Co(phen)_2gly]Cl_2.4H_2O,has been prepared by glycinereacted with cis-[Co(phen)_2Cl_2]Cl,then isolated by SP-Sephadex C-25 H~+ form column.The crystal and molecular structure of the new compound has been determined by RIGAKUAFC5R four circle diffractometer,5032 independent reflections were collected ofwhich 3781 observable reflections were used for structure refinement.The crystal ismonoclinic,space group C2/c,with a=35.13(1),b=9.637(3),c=17.485(6),β=115.08(Z)~,V=5362(3),Z=8.The structure was refined by full matrix least-squaresprocedure to a final R=0.041 and R_=0.060.The molecular formula was CoC_(28)H_(28)N_5O_8Cl_2.with molecular weight M_r=636.38,D_c=1.58g/cm~3,μ=8.88cm~(-1)and F_((000))=2624.     

Hydrothermal synthesis,structure and properties of copper–bipyridine complexes substituted mono-vacant Keggin arsenotungstate

A new arsenotungstate, [H₂AsW₁₁O₃₉][Cu₃(2,2′-bipy)₃(H₂O)₂(OH)]·2H₂O (1) (2,2′-bipy = 2,2′-bipyridine), has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, UV–Vis, TG and single-crystal X-ray diffraction. The compound 1 represents the first example of copper–bipyridine complexes substituted mono-vacant Keggin polyoxotungstate containing As^V. Compound 1 exhibits fluorescent property at room temperature. Furthermore, compound 1 has been used as a solid bulk-modifier to fabricate bulk-modified carbon paste electrodes (1-CPE) by direct mixing. The electrochemical behavior and electrocatalysis of 1-CPE have been studied in detail.     

Synthesis,characterization and property study of new coordination polymers constructed from flexible dicarboxylates and bidentate nitrogen mixed ligands

Five new coordination polymers, [Cd(1,2′-cy)_0.5(bix)H₂O]_n (1), [Cd₂(1,2′-cy)₂(1,10′-phen)₂(H₂O)₂] (2), {[Co(1,2-cy)(2,2′-bipy)(H₂O)₂]·2H₂O}_n (3) {[Cd(succ)(1,10′-phen)H₂O]·H₂O}_n (4), and {[Cd(succ)(2,2′-bipy)H₂O]·2H₂O}_n (5) (1,2-cy = 4-cyclohexene-1,2-dicarboxylate, succ = succinic acid, bix = 1,4-bis(imidazol-1-ylmethyl)benzene, 1,10′-phen = 1,10-phenanthroline, 2,2′-bipy = 2,2′-bipyridine), have been synthesized and characterized by single-crystallographic X-ray diffraction. Complex 1 shows a two-dimensional covalent layer structure. Complex 2 exhibits a two-dimensional supramolecular layer network composed from discrete fundamental units. Complex 3 exhibits a one-dimensional covalent chain-like structure, which further extends to a two-dimensional supramolecular structure with hydrogen bonding and π-π interactions respectively. Complexes 4 and 5 show three-dimensional supramolecular networks composed from one-dimensional chain-like covalent structures. Furthermore, the magnetic property of complex 3 and fluorescent properties of complexes 1, 2, 4 and 5 have also been studied.     

Syntheses,crystal structures and properties of dinuclear copper(I) complexes

Two dinuclear molecule-bridged Cu(I) complexes, (μ-bpym)[Cu(PPh₃)Cl]₂ (1), [(μ-bpym)(CuL)₂](ClO₄)₂·(CH₃CN)₂(H₂O) (2) (bpym = 2,2′-bipyrimidine, L = (R)-(+)-2,2′-bis(diphenylphospho)-1,1′-dinaphthalene) have been synthesized and characterized. The molecular structures of the two new dinuclear compounds exhibit bridging of two copper(I) centers by the symmetrically bis-chelating bpym ligand. Intriguingly, compound 1 features a remarkable “intramolecular organic sandwich” configuration where the central 2,2′-bipyrimidine bridging ligand interacts in π/π/π fashion with two phenyl rings from the coligands above and below the central plane, while chiral compound 2 exhibits second-order nonlinear optical effect and temperature-dependent luminescence. Upon decreasing the temperature from 298 to 10 K, compound 2 shows a red light emission.     

Synthesis,structure and characterization of new 1D and 2D Ni(II) coordination polymers

Two new Ni(II) coordination polymers, namely [Ni₃(Hsdac)₂(sdac)₂(2,2′-bipy)₂] (1) and [Ni₂(sdac)₂(4,4′-bipy)₂]·2H₂O (2) (sdba = 4,4′-sulfonyldibenzoate, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), have been prepared under hydrothermal conditions and characterized by single crystal X-ray diffraction analyses. Compound 1 possesses an interesting chain structure. Adjacent chains are further linked through H-bond interactions between Hsdac ligands to give a two-dimensional (2D) supramolecular architecture. Compound 2 displays an unusual 2D polyrotaxane-like network.     

Syntheses,structures and magnetic studies of three heterometallic Fe2Ln 1D coordination polymers

Three new heterometallic 1D coordination polymers [Fe^III₂Pr(4-Me-sal)₄(2,2′-bipy)₂(H₂O)₆](NO₃) · 2MeOH · 1.5H₂O (1), [Fe^III₂Gd(4-Me-sal)₄(2,2′-bipy)₂(H₂O)₅]Cl_1/2(NO₃)_1/2 · 5H₂O (2) and [Fe^III₂Dy(4-Me-sal)₄(2,2′-bipy)₂(H₂O)₅]Cl_1/2(NO₃)_1/2 · 5H₂O (3) have been synthesized. 1 and 2 were characterized by single-crystal X-ray crystallography, and 3 was shown to be isomorphous to 2 by X-ray powder diffraction. Magnetic studies show that the three compounds show a similar temperature dependence of their magnetic susceptibilities over the range 1.8–300 K. The observed decrease of χT with decreasing temperature for all three compounds could be the result of antiferromagnetic interactions between Fe–Ln centres and/or the depopulation of the Stark sublevels in the case of the anisotropic Ln ions (Pr^III and Dy^III).     

Dual-ligand approach to the synthesis of new luminescent cadmium(II) coordination polymers with one- and two-dimensional homochiral structures

Two new homochiral cadmium(II) coordination polymers, Cd₂(bipy)₂(H₂O)₂ (cam)₂ (1) and Cd₂(phen)₂(cam)₂·eg (2), where bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline, H₂cam = (1R, 3S)-(+)-camphoric acid, and eg = ethylene glycol, have been synthesized by a dual-ligand approach. Compound 1 possesses a chain-like architecture and compound 2 has a layered structure with a (4,4) grid topology. Both compounds crystallize in the space group C2 and exhibit intense photoluminescence upon photoexcitation at 280 and 300 nm, respectively.     

Two novel Keggin tungstocobaltates grafted by cobaltII complex group(s): K[Co(phen)2(H2O)]2[HCoW12O40]·2H2O and [Co(2,2′-bipy)3]1.5{[Co(2,2′-bipy)2(H2O)][HCoW12O40]}·0.5H2O

Two novel inorganic–organic hybrid compounds composed of Keggin tungstocobaltate framework and cobalt(II)–N coordination complexes, K[Co(phen)₂(H₂O)]₂[HCoW₁₂O₄₀]·2H₂O (1) (phen = 1,10-phenanthroline) and [Co(2,2′-bipy)₃]_1.5{[Co(2,2′-bipy)₂(H₂O)][HCoW₁₂O₄₀]·0.5H₂O (2) (bipy = bipyridine), have been synthesized under hydrothermal conditions by directly using Keggin POMs as starting materials, which were characterized by elemental analyses, IR, TG analyses and X-ray single crystal diffraction. Crystal data for compound 1: C₄₈H₄₁Co₃KN₈O₄₄W_12, triclinic, space group P-1, a = 10.918(5) Å, b = 13.401(5) Å, c = 13.693(5) Å, α = 69.291(5)°, β = 71.568(5)°, γ = 78.421(5)°, V = 1768.9(12) Å³, Z = 1; for compound 2: C₁₃₀H₁₀₄Co₇N₂₆O₈₃W_24, orthorhombic, space group, C2/c, a = 46.839(9) Å, b = 14.347(3) Å, c = 26.147(5) Å, α = β = γ = 90°, V = 17,570(6) Å³, Z = 4. Compound 1 exhibits a pseudo-1D chainlike structure, in which potassium ions act as linkages of Keggin unit doubly grafted by [Co(phen)₂(H₂O)] complex. Compound 2 represents a [Co(2,2′-bipy)₂(H₂O)]²⁺ mono-grafted Keggin tungstocobaltate derivative with 1.5[Co(2,2′-bipy)₃]²⁺ countercations. The cyclic voltammetric behavior of 1-CPE is similar to the parent 3-CPE, but the cyclic voltammetric behavior of Co^II shows a little difference. Variable-temperature magnetic susceptibility measurement of compound 1 demonstrates the presence of antiferromagnetic interactions.     

Complexes derived from the copper(II) perchlorate/maleamic acid/2,2′-bipyridine and copper(II) perchlorate/maleic acid/2,2′-bipyridine reaction systems: Synthetic,reactivity, structural and spectroscopic studies

A systematic investigation of the reactions of Cu(ClO₄)₂ · 6H₂O with maleamic acid (H₂L) in the presence of 2,2′-bipyridine (bpy) has been carried out. The chemical and structural identity of the products depends on the solvent, the absence or presence of external hydroxides in the reaction mixture and the molar ratio of the reactants. Various reaction schemes have led to the isolation of the complexes [Cu₂(HL)₂(bpy)₂(H₂O)₂](ClO₄)₂ (1), [Cu₂(HL)₂(bpy)₂(H₂O)₂](ClO₄)₂ · 2H₂O (1 · 2H₂O), [Cu(L′′)(bpy)]_n · 2nH₂O (2 · 2nH₂O), [Cu₂(L′′)(bpy)₂(H₂O)₂]_n(ClO₄)_2n · 0.5nH₂O (3 · 0.5nH₂O), [Cu₂(L′′)₂(bpy)₂] · 2MeOH (5 · 2MeOH), [Cu₂(L′)₂(bpy)₂(ClO₄)₂] (6) and [Cu(ClO₄)₂(bpy)(MeCN)₂] (7b), where L′′^2? and L′^? are the maleate(?2) and monomethyl maleate(?1) ligands, respectively. The HL^? ion has been transformed to L′′^2? and L′^? in the known compounds 2 · 2nH₂O and 6, respectively, via metal ion-assisted processes involving hydrolysis (2 · 2nH₂O) and methanolysis (6) of the primary amide group. The reaction that leads to 6 takes place through the formation of the mononuclear complex [Cu(ClO₄)₂(bpy)(MeOH)₂] (7a), whose structure was assigned on the basis of its spectral similarity with the structurally characterized complex 7b. The structures of the cations in 1 and 1 · 2H₂O consists of two Cu^II atoms bridged by the carboxylate groups of the two HL^? ligands, each exhibiting the less common η² coordination mode; a chelating bpy molecule and a H₂O ligand complete square pyramidal coordination at each metal centre. The structure of the dinuclear repeating unit in the 1D coordination polymer 3 · 0.5nH₂O consists of two Cu^II atoms bridged by two syn,syn η¹:η¹:μ₂ carboxylate groups belonging to two L′′^2? ions; each ligand bridged two neighboring [Cu^II,II₂] units thus promoting the formation of a helical chain. The structure of the dinuclear molecule of complex 5 · 2MeOH consists of two Cu^II atoms bridged by two η² carboxylate groups from two L′′^2? ligands; the second carboxylate group of each maleate(?2) ligand is monodentately coordinated to Cu^II, creating a remarkable seven-membered chelating ring. The L′^? ion behaves as a carboxylate-type ligand in 6, with the carboxylate group being in the familiar syn,syn η¹:η¹:μ₂ coordination mode; a chelating bpy molecule and a coordinated ClO₄^? complete five-coordination at each Cu^II centre. The crystal structures of the complexes are stabilized by various H-bonding patterns. Characteristic IR bands of the complexes are discussed in terms of the known structures and the coordination modes of the ligands.     

Synthesis and characterization of thiosemicarbazone derivatives of 2-chloro-4-hydroxy-benzaldehyde and their rhenium(I) complexes

N-Thioamide thiosemicarbazone derived of 2-chloro-4-hydroxy-benzaldehyde (R = H, HL¹; R = Me, HL² and R = Ph, HL³) have been prepared and their reaction with fac-[ReX(CO)₃(CH₃CN)₂] (X = Br, Cl) in chloroform gave the adducts [ReX(CO)₃(HL)] (1a X = Cl, R = H; 1a′ X = Br, R = H; 1b X = Cl, R = CH₃; 1b′ X = Br, R = CH₃; 1c X = Cl, R = Ph; 1c′ X = Br, R = Ph) in good yield. Complexes 1a′ and 1b’ were also obtained by the reaction of HL¹ and HL³ with [ReBr(CO)₅] in toluene.All the compounds have been characterized by elemental analysis, mass spectrometry (FAB), IR and ¹H NMR spectroscopic methods. Moreover, the structures of HL², HL³ and 1a·H₂O were also established by X-ray diffraction. In 1a, the rhenium atom is coordinated by the sulphur and the azomethine nitrogen atoms, forming a five-membered chelate ring, as well as three carbonyl carbon and chloride atoms. The resulting coordination polyhedron can be described as a distorted octahedron.The study of the crystals obtained by slow evaporation of methanol and DMSO solutions of the adducts 1a′ and 1b, respectively, showed the formation of dimer structures based on rhenium(I) thiosemicarbazonates [Re₂(L¹)₂(CO)₆]·3H₂O (2a)·3H₂O and [Re₂(L²)₂(CO)₆]·(CH₃)₂SO (2b)·2(CH₃)₂SO. Amounts of these thiosemicarbazonate complexes [Re₂(L)₂(CO)₆] (2) were obtained by reaction of the corresponding free ligands with [ReCl(CO)₅] in dry toluene.In 2a·3H₂O and 2b·2(CH₃)₂SO the dimer structures are established by Re–S–Re bridges, where S is the thiolate sulphur from a N,S-bidentate thiosemicarbazonate ligand. In both structures the rhenium coordination sphere is similar; the dimers are in the same diamond Re₂S₂ face.     

Carboxylic-supported copper complexes as catalyst for the green oxidative coupling of 2,6-dimethylphenol: Synthesis,characterization and structure

Three new Cu(II) complexes with carboxylic ligand, namely {[Cu(qc)₂(py)]·4H₂O}_∞ (1), [Cu(qc)₂(4,4′-bpy)]_∞ (2) and [Cu(pc)(2,2′-bpy)(H₂O)]₂·H₂O (3) (Hqc = 3-hydroxy-2-quinoxalinecarboxylic acid, H₂pc = 4-hydroxyphthalic acid, py = pyrazine) have been synthesized and characterized. In both 1 and 2, each Cu(II) ion is coordinated by two quinoxalinecarboxylate moieties in the equatorial plane and two 4,4′-bpy or pyrazine units provide coordination in the axial positions, thus, resulting in a 1-D polymeric chain structure. Complex 3 has a dimeric structure in which two Cu(II) cations are bridged by two deprotonated pc^2? ligands and two 2,2′-bpy molecules. As heterogeneous catalysts, the title complexes showed high catalytic efficiency in the green oxidative polymerization of 2,6-dimethylphenol (DMP) to poly(1,4-phenylene ether) (PPE) in the presence of H₂O₂ as oxidant in water under mild conditions. Moreover, they allow reuse without significant loss of activity through four runs, which suggests that these catalysts are efficient, mild, and easily recyclable for the oxidative coupling of DMP. The preliminary study of the catalytic–structural correlations suggests that the coordination environment of the metal center plays an important role in the improvement of their catalytic efficiencies.