Syntheses,Structures and Magnetic Properties of Two Coordination Polymers Based on 2, 2-Biphenyldicarboxylate Ligand

Two coordination polymers {[Co₃L₃(Me₂NH)₂]·(Me₂NH)}_n(1) and [CuL(bpy)]_n(2)(L=2,2'-biphenyl dicarboxylate ion, bpy=4,4'-bipyridine) were obtained and characterized. Compound 1 was synthesised via solvothermal method, with the L ligands adopting syn-syn-μ₂-η¹:η¹- and μ₂-η²-coordination modes and Co(II) centers being linked to form a 1D coordination chain with trinuclear Co₃ cluster as sub-units. Compound 2 was synthesized at room temperature, with the L ligand chelating the Cu(II) centers to form a 1D chain, which was further linked by the auxiliary 4,4'-bpy ligand to form a 3D coordination network. The results of variable temperature susceptibility studies reveal that there were ferromagnetic and antiferromagnetic interactions between the paramagnetic metal centers in compounds 1 and 2, respectively.     

Syntheses,Structures, and Properties of Five Coordination Polymers Involving Phthalic Acid

Five new coordination polymers Cu(phen)(H2O)(phth)·CH3OH(1), [Cu(2,2'-bipy)(H2O)](phth)·3.5H2O(2), Zn(phen)(phth)(H2O)·1.125H2O(3) and [M(4,4'-bipy)(H2O)2](phth)·2H2O[M=Zn(4), Mn(5)](H2phth=phthalic acid, bipy=bipyridine, phen=1,10-phenanthroline) have been synthesized from the amino acid derivatives(phthalyl-l- valine, H2L) and structurally characterized. H2L was hydrolyzed into phth2– group during the reaction, but the strucure feature was different from that of the complex directly synthesized from H2phth in the reported literature, revealing that H2L played an important role in composing the novel compounds. Compounds 1, 2 and 3 are all 1D chains, but the differences are that compound 1 is further hydrogen-bonded into 2D networks, and compound 2 is further extended into 3D supramolecular network through π-π stacking and hydrogen-bonding interactions. However, compound 3 is a 1D helix chain structure and further links into 2D networks through π-π stacking. Compounds 4 and 5 are isostructural and exhibit the same 2D layers, which are further connected by hydrogen-bonding interactions to form 3D supramolecular network. Antiferromagnetic superexchange was observed for compounds 1, 2 and 5.     

Four Transition Metal Coordination Polymers based on an Aromatic Multi‐carboxylic Acid as Ligand: Syntheses,Crystal Structures,and Fluorescent/Magnetic Properties

Four compounds, namely, [Zn(H₂L)₂ · 4H₂O] ( 1 ), [Cu(HL) · (H₂O)] · H₂O ( 2 ), [Ni₃L₂(bpy)₂ · 12H₂O] · 4H₂O ( 3 ), and [Co₃L₂(bpy)₂ · 12H₂O] · 4H₂O ( 4 ) [H₃L = 4, 4′‐[(5‐carboxy‐1, 3‐phenylene)bis(oxy)]dibenzoic acid], were synthesized under solvothermal conditions by employing a semi‐rigid aromatic multi‐carboxylic acid ligand (H₃L) and ancillary nitrogen ligand (bpy = 4, 4′‐bipyridine). X‐ray diffraction studies revealed that complexes 1 , 3 , and 4 show zero‐dimensional (0D) structures, which were further extended to distinct 3D supramolecular nets by extensive hydrogen‐bond interactions. However, in compound 2 , 1D chains of square‐shaped pores were linked together by HL^2– ligands to generate a 2D porous layer along the ac plane. Comparison of the structures indicated that not only the conformation of the functional ligand, but also the ancillary ligand helped in structural determination of the compounds. Compound 1 exhibited solid fluorescence emission originating from an intraligand π→π* transition. Magnetic susceptibility measurements demonstrated that compound 2 exhibited antiferromagnetic coupling between adjacent copper(II) ions, with the corresponding J values of –141.84 cm^–1. Furthermore, the thermal behaviors of the complexes 1 – 4 were studied by thermogravimetric analysis.     

Syntheses,Crystal Structures,and Properties of Metal(II) Coordination Polymers based on Flexible Ligand 1,3‐Bis(4‐phenoxy)benzenedicarboxylic Acid and Bis(benzimidazole)

Three new coordination polymers, [Zn(PBDC)(bbbm)_0.5]_n ( 1 ), [Co(PBDC)(bbbm)]_n ( 2 ), and [Cd(PBDC)(bbbm)]_n ( 3 ) were prepared via hydrothermal reactions of different metal(II) nitrates with flexible 1,3‐bis(4‐phenoxy)benzenedicarboxylic acid (H₂L) and 1,1‐(1,4‐butanediyl)bis(benzimidazole) ligand. All these complexes were fully characterized by elemental analysis, FT‐IR, thermogravimetric analysis (TGA), powder X‐ray diffraction, and single‐crystal X‐ray diffraction. Structure analyses revealed that complex 1 has a 2D→2D twofold interpenetrating framework simplified by a 4‐connected sql net with point symbol (4⁴.6²), whereas complexes 2 and 3 are isostructural and exhibit a 2D→2D twofold interpenetrating framework rationalized as a three‐connected hcb net with point symbol (6³). Complexes 1 – 3 further expand to 3D supramolecular structures through non‐covalent C–H ··· O interactions. Additionally, the luminescent and magnetic properties of some of these complexes were studied. Complex 3 presents ideal photoluminescent behavior, whereas complex 2 shows antiferromagnetic coupling between the central Co^II ions, suggesting its latent application in magnetic material.     

Two Coordination Polymers based on a Flexible Tritopic Pyridyldicarboxylate Ligand: Structures and Magnetic Properties

The coordination polymers, [Ni(L)₂]_n ( 1 ) and [Mn₂(L)₂(DMF)₂(H₂O)]_n ( 2 ) were synthesized by using a tritopic ligand 5‐(4′‐carboxylphenoxy)nicotinic acid (H₂L). The structural analysis shows that compound 1 exhibits a ten‐connected three‐dimensional (3D) architecture with the point symbol 3¹².4²⁶.5⁷, 2 displays an eight‐connected topology network with a point symbol of 4²⁴.6⁴. The structures and formulas of 1 and 2 were determined by X‐ray diffraction, elemental analysis, and thermogravimetric analysis (TGA). In addition, the magnetic behaviors for 1 and 2 were investigated.     

Solvothermal Syntheses,Crystal Structures,and Luminescent Properties of Two Coordination Polymers with Different Interpenetrated Diamond Topology

Two coordination polymers, namely, {[Zn(bpea) (bmp)] · H₂O}_n ( 1 ) and {[Ni(bpea)(bimb)] · DMF}_n ( 2 ) [H₂bpea = biphenylethene‐4,4′‐dicarboxylate, bmp = 1,4‐bis(2‐methylimidazol‐3‐ium‐1‐yl)biphenyl and bimb = 1,4‐bis(1‐imidazol‐yl)‐2,5‐dimethyl benzene], were synthesized under solvothermal conditions with mixed organic ligands. Single crystal X‐ray diffraction reveals that complex 1 features a three‐dimensional (3D) structure with a sixfold interpenetrating dia net. Complex 2 shows a 3D fivefold interpenetrating dia topology. Furthermore, the solid state luminescent properties of complexes 1 and 2 were investigated at room temperature.     

两种异金属链状配位聚合物的合成和晶体结构

在甲醇溶液中,将K2NiL·H2O和M(OAC)2(M = Co,Zn)按1:1的摩尔比进行组装反应,得到了镍、钴和镍、锌两种异金属一维链状配位聚合物,其化学组成分别为{[Ni2Co2L2(H2O)2]·CH3OH·3H2O}n（1）和{[Ni2Zn2L2 (H2O)2]·2CH3OH·H2O}n（2）,（H4L=2-羟基-3-[(E)-({2-(2-羟基苯甲酰胺基)乙基}亚氨基)甲基]苯甲酸,OAC- = CH3COO-）。通过IR谱,元素分析的方法对其进行了表征,利用X-射线单晶衍射方法对其晶体结构进行了测定,结构分析表明：它们都是由不对称四核单元组成链状配位聚合物。     

Three New Lanthanide Coordination Polymers Built from H2bpdc Ligands: Syntheses,Structures, and Properties

Three new lanthanide‐organic coordination polymers, {[Ln₂(bpdc)₂(H₂O)₆(NO₃)] · NO₃} [Ln = La ( 1 ), Ce ( 2 ), Pr ( 3 )] (H₂bpdc = 2, 2′‐bipyridine‐6, 6′‐dicarboxylic acid) were synthesized under hydrothermal conditions and structurally characterized by elemental analysis, IR spectroscopy as well as single‐crystal and powder X‐ray diffraction. Single‐crystal X‐ray diffraction analysis revealed that compounds 1 – 3 are isostructural, composed of two dimensional honeycomb network linked by bpdc ligands. The magnetic property of compound 3 was investigated.     

Syntheses,Structures, and Catalytic Properties of Three Copper(II) Coordination Polymers Based on 2,3,5,6‐Tetrafluoro‐1,4‐bis(triazole‐ylmethyl)benzene and Benzene Carboxylate Ligands

Three new mixed‐ligand coordination polymers of Cu^II, namely, [Cu(Fbtx)(L1)(H₂O)]_n ( 1 ), [Cu(Fbtx)_0.5(HL2)(H₂O)₂]_n ( 2 ), and {[Cu(Fbtx)_1.5(HL3)(H₂O)] · H₂O}_n ( 3 ) [Fbtx = 2,3,5,6‐tetrafluoro‐1,4‐bis(1,2,4‐triazole‐1‐ylmethyl)benenze, H₂L1 = terephthalic acid, H₃L2 = trimesic acid, NaH₂L3 = 5‐sulfoisophthalic acid monosodium salt], were hydrothermally synthesized and structurally characterized by elemental analysis, IR spectra, and single‐crystal and powder X‐ray diffraction techniques. All the complexes have a two‐dimensional (2D) coordination layer structure. Of these, 1 displays a planar 4⁴‐ sql structure whereas both 2 and 3 are highly undulated 6³‐ hcb nets. Moreover, their thermal stability and catalytic behaviors in the aerobic oxidation of 4‐methoxybenzyl alcohol were also investigated as well. The results indicate that the benzene dicarboxylate ligands have an effective influence on the structures and catalytic properties of the resulting coordination polymers.     

Two CdII/CoII‐Imidazolate Coordination Polymers: Syntheses,Crystal Structures,Stabilities, and Luminescent/Magnetic Properties

Cadmium(II) based 2D coordination polymer [Cd(L1)₂(DMF)₂] ( 1 ) (L1 = 4,5‐dicyano‐2‐methylimidazolate, DMF = N,N′‐dimethylformamide) and 2D cobalt(II)‐imidazolate framework [Co(L3)₄] ( 2 ) (L3 = 4,5‐diamide‐2‐ethoxyimidazolate) were synthesized under solvothermal reaction conditions. The materials were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X‐ray diffraction measurement (PXRD) and single‐crystal X‐ray diffraction. Compound 1 has hexacoordinate Cd^II ions and forms a zigzag chain‐like coordination polymer structure, whereas compound 2 exhibits a 2D square grid type structure. The thermal stability analysis reveals that 2 showed an exceptional thermal stability up to 360 °C. Also, 2 maintained its fully crystalline integrity in boiling water as confirmed by PXRD. The solid state luminescent property of 1 was not observed at room temperature. Compound 2 showed an independent high spin central Co^II atom.     

Tuning the Topological Net via the Metal Ion‐Driven Assembly of Two ZnII / CdII Coordination Polymers: Syntheses,Crystal Structures,and Luminescent Properties

The coordination polymers {[Zn₂(HIDC)₂(tib)] · H₂O}_n ( 1 ) and {[Cd(HIDC)(tib)] · H₂O}_n ( 2 ) [H₃IDC = 1H‐imidazole‐4, 5‐dicarboxylic acid, tib = 1, 3,5,‐tris(1‐imidazolyl) benzene] were obtained under hydrothermal conditions. Their structures were determined by single‐crystal X‐ray diffraction analysis and further characterized by elemental analysis and IR spectroscopy. Complex 1 exhibits a two‐dimensional layer structure with a 6³‐hcb topology. Complex 2 has a three‐dimensional structure with a pcu topology. It is shown that the carboxylate ligand can bear diverse structures regulated by metal ions. Additionally, the photoluminescence behaviors of complexes 1 and 2 are discussed.     

Synthesis,Crystal Structures,Thermal and Magnetic Properties of New Selenocyanato Coordination Polymers with Pyrazine as Co‐Ligand

Reaction of iron(II), cobalt(II) and nickel(II) selenocyanate with pyrazine in water at room temperature leads to the formation of the isotypic new ligand‐rich 1:2 (1:2 = ratio between metal and co‐ligand) compounds [M(NCSe)₂(pyrazine)₂]_n (M = Fe ( 1 ), Co ( 2 ), Ni ( 3 )). The crystal structure of 2 was determined by X‐ray single crystal analysis and those of 1 and 3 were refined from X‐ray powder data with the Rietveld method. In their crystal structure the metal(II) cations are coordinated by four pyrazine co‐ligands, which connect them into layers, and two terminally N‐bonded selenocyanato anions in a distorted octahedral arrangement. The terminal coordination mode of the selenocyanato anions was further emphasized by IR spectroscopic investigations. On heating, all compounds decompose in a single heating step without the formation of ligand‐deficient intermediates like previously reported for related thiocyanato compounds. Magnetic measurements of compound 1 show a long‐range antiferromagnetic ordering with an ordering temperature of T_N = 6.7 K, which must be mediated by the aromatic π‐system of the pyrazine ligand, whereas 2 and 3 show only Curie–Weiss behavior with antiferromagnetic exchange interactions.     

Solvent Effect on the Assembly of Two Cadmium(II) Coordination Polymers Derived from 3,3′‐(Diazenediyl)dibenzoic Acid: Syntheses,Structures, Stabilities,and Photocatalytic Properties

Abstract. Two cadmium(II) coordination polymers, {CdL₂[(CH₃)₂NH₂]₂ · 2DMF}_n ( 1 ) and {[Cd₃L₄[(CH₃)₂NH₂]₂] · EtOH · 2DMF}_n ( 2 ) were synthesized from the solvothermal reactions of Cd(OAc)₂ · 2H₂O with 3,3′‐(diazenediyl)dibenzoic acid (H₂L) in different solvents. Both complexes were characterized by elemental analysis, IR spectroscopy, powder X‐ray diffraction, TG analysis, and single‐crystal X‐ray diffraction. In compound 1 , central cadmium(II) atoms were linked with the surrounding L ligands to generate an infinite 1D chain with repeated rings. Compound 2 displayed a 3D threefold interpenetrating framework based on cage‐like [Cd₃L₆]₈ species and exhibited a 4¹²6³ topological structure. The results demonstrated that the different solvents had significant effect on the construction of different coordination compounds from the same components. In addition, they exhibited excellent stability and good photocatalytic activity towards the degradation of methylene blue in aqueous solution under UV irradiation.     

Syntheses,Structures, and Magnetic Properties of Two Novel Cobalt(II) Coordination Polymers Constructed from Pyridine‐2,6‐dicarboxylic Acid N‐oxide (PDCO)

Two new cobalt(II) coordination polymers, [Co(PDCO)(H₂O)₂]_n ( 1 ) and [Co(PDCO)(bix)(2H₂O)₂·H₂O]_n ( 2 ) ( PDCO= pyridine‐2,6‐dicarboxylic acid N‐oxide, bix = 1,4‐bis(imidazol‐1‐ylmethyl)‐benzene) have been synthesized under hydrothermal conditions. Single‐crystal X‐ray analyses show that compound 1 is a 1D helical chainlike structure with 4₁ screw axes parallel to the crystallographic c‐axis and interchain hydrogen‐bonding interactions further result in a 3D framework; for compound 2 , each bix ligand connects two Co1 atoms (or two Co2 atoms) to give a zigzag chain structure and these 1D chains are connected by offset face‐to‐face π···π and hydrogen bond interactions to generate a 3D architecture. The thermogravimetric analyses were investigated for 1 and 2 . The determination of variable temperature magnetic susceptibilities indicates an antiferromagnetic interaction between the metal atoms for 1 and 2 .     

Influence of the Different Dicarboxylate Ligands on The Topological Net of Manganese(II) Coordination Polymers: Syntheses,Crystal Structures. and Luminescent Properties

The self‐assembly of Mn^II ions and 1,4‐bis(2‐methyl‐imidazole‐1‐yl)benzene (bip) with two different dicarboxylate ligands, benzophenone‐4,4′‐dicarboxylic acid (H₂bda) and 1,4‐naphthalenedicarboxylic acid (H₂nda) via hydrothermal synthesis resulted in two interesting coordination polymers, [Mn(bda)(bip)]_n ( 1 ) and [(Mn(nda)(bip)_0.5(H₂O)]_n ( 2 ). Their structures were determined by single‐crystal X‐ray diffraction and elemental analyses, as well as IR spectroscopy. Complex 1 exhibits an unusual polycatenated 2D+2D→3D framework. Complex 2 shows a twofold interpenetrated pcu net. In addition, the solid‐state photoluminescent properties of 1 and 2 were investigated at room temperature.     

Syntheses,Structures, and Photophysical Properties of Two Coordination Polymers Based on 2,3‐Dioxo‐1,2,3,4‐tetrahydroquinoxaline‐6‐carboxylic Acid

Two complexes based on the ligand 1,4‐dihydro‐2,3‐quinoxalinedione, namely [Mn(H₂L)₂(H₂O)₂]_n ( 1 ) and {[Zn₂(H₂L)₂(tz)₂] · 5H₂O}_n ( 2 ) (H₃L = 2,3‐dioxo‐1,2,3,4‐tetrahydroquinoxaline‐6‐carboxylic acid, Htz = 1,2,4‐triazole) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, as well as single‐crystal and powder X‐ray diffraction. Complex 1 exhibited a 1D comb‐like chain formed by H₂L^– anions linking Mn^II ions, whereas complex 2 was a 2D layer‐like structure with square‐shaped windows and outstretched arms built by combination of H₂L^– and tz^– ligands with Zn^II ions. The adjacent chains or layers connected with each other by intermolecular hydrogen bonding and π–π stacking to further extend to a 3D supermolecular framework. In addition, the thermal stabilities, luminescence properties, and optical energy gap of 1 and 2 were investigated in detail.     

Synthesis,Structure, Magnetic Properties,and Catalase‐like Activity of Methoxy‐bridged Manganese(III) Coordination Polymer containing Hydrazone based (O,N,O)2‐Donor Ligand

A 1D coordination polymer of manganese(III) with a hydrazone‐based ligand, [Mn₂(L)(μ‐OCH₃)₂(OHCH₃)₂]_n ( 1 ), was synthesized and characterized by elemental analyses and spectroscopic methods {H₄L = bis[(2‐hydroxynaphthalen‐1‐yl)methylene]adipohydrazide}. The crystal structure of 1 was determined by X‐ray crystallography. The two dianionic domains of the ligand adopt trans configuration, and each coordinates in a tridentate mode via the O, N, O′‐donor atoms to a Mn^III ion forming a dinuclear compound. The methoxy ligands provide an asymmetric bridge between two central manganese atoms, which lead to the formation of a 1D coordination polymer. A 2D supramolecular structure is formed by hydrogen bonding interactions between the 1D chains. Although the methoxy ligands are labile, the polymer preserves its oligonuclearity in the solution. Temperature‐dependent magnetic susceptibility studies proved the presence of a weak antiferromagnetic interaction between manganese(III) ions with J = –3.2 cm^–1, which results from axial distortion of the manganese coordination environment. Compound 1 showed catalase‐like activity in disproportionation of H₂O₂.     

钴、镍-氨基三乙酸配位聚合物Na[M(nta)]·H2O(M=Co,Ni)的水热合成、结构与磁性

由有机配体同金属离子作用构建的配位聚合物具有与无机微孔晶体类似的空旷骨架结构,并在非线性光学材料、磁性材料、超导材料及催化等诸多方面具有潜在的应用前景[1～4].在配位聚合物的合成中,配体的种类不仅直接影响到聚合物的合成,而且还涉及到聚合物的结构维数[5～7].目前,用来构建这些配合物的有机配体大多数都带有相同的可配位基团,较少应用具有两种以上的配位基团的有机配体.本文采用同时含有氮和氧两种配位原子的多齿配体氨基三乙酸[8～12],在水热条件下分别以Co2+和Ni2+作为组装基元,通过自组装合成了具有三维骨架结构的Na[M(nta)]·H2O [M=Co(1),Ni(2)]配位聚合物,并进行了结构与磁性研究.     

Three Novel 1‐H‐Benzimidazole‐5‐Carboxylate‐Based Nickel(II)/Cobalt(II) Coordination Polymers: Synthesis,Crystal Structures,Luminescent, and Magnetic Properties

Three 1H‐benzimidazole‐5‐carboxylate (Hbic^–)‐based coordination polymers, {[Ni(H₂O)(Hbic)₂] · 2H₂O}_n ( 1 ), {[Ni(H₂O)₂(Hbic)₂] · 3H₂O}_n ( 2 ), and {[Co₂(H₂O)₄(Hbic)₄] · 4DMF · 3H₂O}_n ( 3 ) were obtained by reactions of the ligand H₂bic and Ni^II or Co^II salts in the presence of different structure directing molecules. They were structurally characterized by single‐crystal X‐ray diffraction, IR spectra, elemental analysis, thermal stability, luminescent, and magnetic measurements. Structural analysis suggests that the three polymers exhibit a 2D (4, 4) layer for 1 and 1D linear double chains for both 2 and 3 due to the variable binding modes and the specific spatial orientation of the Hbic^– ligand towards the different paramagnetic metal ions, which were further aggregated into different 3D supramolecular architectures by popular hydrogen‐bonding interactions. Weak and comparable antiferromagnetic couplings mediating by Hbic^– bridge are observed between the neighboring spin carriers for 2 and 3 , respectively. Additionally, complexes 1 – 3 also display different luminescence emissions at room temperature due to the ligand‐to‐metal charge transfer.     

Two 3d‐4f Heterometallic Coordination Polymers of Macrocyclic Oxamide with Benzotriazole‐5‐carboxylate Co‐ligand: Syntheses,Crystal Structures and Magnetic Properties

Two heterometallic 3d–4f coordination polymers, [Gd(CuL)₂(Hbtca)(btca)(H₂O)] · 2H₂O ( 1 ) and [Er(CuL)₂(Hbtca)(btca)(H₂O)] · H₂O · CH₃OH ( 2 ) (CuL, H₂L = 2,3‐dioxo‐5,6,14,15‐dibenzo‐1,4,8,12‐tetraazacyclo‐pentadeca‐7,13‐dien; H₂btca = benzotriazole‐5‐carboxylic acid) were synthesized by solvothermal methods and characterized by single‐crystal X‐ray diffraction. Complexes 1 and 2 exhibit a double‐strand meso‐helical chain structures formed by [Ln^IIICu^II₂] (Ln^III = Gd, Er) units by oxamide and benzotriazole‐5‐carboxylate bridges. They are isomorphic except that one free water molecule of 1 is replaced by a methanol molecule. All 1D chains are further interlinked by hydrogen bonds resulting in a 3D supramolecular architecture. The magnetic properties of the compound 1 and 2 are also discussed.