Solvothermal synthesis of 1D and 2D cobalt(II) and nickel(II) coordination polymers with 2,5-dihydroxy-p-benzenediacetic acid

1D cobalt(II) and nickel(II) coordination polymers {[Co(dba)(H₂O)₄] · H₂O}_n (1) and {[Ni(dba)(H₂O)₄] · H₂O}_n (2) (H₂dba = 2,5-dihydroxy-p-benzenediacetic acid) were synthesized under low temperature solvothermal condition. When 4,4′-bipyridine (bpy) was introduced to the synthetic systems of 1 and 2, respectively, two novel 2D coordination polymers {[Co(dba)(bpy)] · 0.5H₂O}_n (3) and [Ni(dba)(bpy)(H₂O)₂]_n (4) with different structures were obtained. All of the compounds were characterized by elemental analysis, FT-IR, UV–Vis spectra and single crystal X-ray diffraction.     

Synthesis and structural characterization of copper(II) coordination polymers with 1,1,2,2-tetra(pyrazol-1-yl)ethane

Reaction between 1,1,2,2-tetra(pyrazol-1-yl)ethane (Pz⁴) and copper(II) nitrate in ethanol at room temperature and in solvothermal conditions (90 °C) lead to coordination polymers of two different structures. A ribbon-like coordination polymer {Cu₂(μ₂-NO₃)₂(H₂O)₄ μ′₂-Pz⁴}_n was formed at room temperature in which nitrate ions bind the monomeric units, while Pz⁴ ligands are responsible for cross-linking of {Cu(μ-NO₃)} chains. At 90 °C linear 1D coordination polymer was formed, in which Pz⁴ ligands bridge copper ions that in addition bear two monodentate nitrate ions.     

Counteranion-directed assembly of zinc(II) coordination polymers with 1,3,5-tris(1-imidazolyl)benzene

Two novel coordination polymers [Zn₂(tib)(chda)Cl₂] (1) and [Zn(tib)I]I (2) have been prepared by reactions of 1,3,5-tris(1-imidazolyl)benzene (tib) and 1,2-cyclohexanedicarboxylic acid (H₂chda) with corresponding Zn(II) salts, respectively. Complex 1 has a three-dimensional (3D) structure with rare gra (graphite) topology, while 2 is a typical two-dimensional (2D) (4·8²) network. The results revealed that the counteranion plays a subtle and important role in the assembly procedure. Photoluminescent property of the complexes was investigated.     

Two nickel coordination polymers with flexible ligand 1,3,5-tri(1,2,4-triazol-1-ylmethyl)-2,4,6-trimethylbenzene

The reaction of 1,3,5-tri(1,2,4-triazol-1-ylmethyl)-2,4,6-trimethylbenzene (ttmb) with Ni(II) salts yields two coordination polymers [Ni₃(ttmb)₂(H₂O)₆Cl₆](H₂O)₃ (1) and [Ni(ttmb)₂(H₂O)₂](NO₃)₂(H₂O)₄ (2). The flexible ligand ttmb shows the cis,cis,cis-conformation and a tri-monodentate coordination mode in 1. Each ttmb links three Ni(II) atoms to form an undulated (3, 4)-connected two-dimensional network. Each undulated two-dimensional network polycatenates other two identical networks, thus giving a rare (2D → 3D) parallel polycatenation network in 1. The ttmb ligand exhibits the cis,trans,trans-conformation and a two-monodentate coordination mode in 2. Each ttmb connects two Ni(II) atoms to construct a two-dimensional (4, 4) network in 2. The thermal stability of compounds 1 and 2 was studied.     

Synthesis and characterization of coordination polymers of Hg(II) with poly(thiooxamides)

Coordination polymers of Hg(II) with dithiooxamide, poly(ethylene thiooxamide), poly(butane thiooxamide), and poly(hexane thiooxamide) have been synthesized. All coordination polymers are solid compounds insoluble in common organic solvents. Coordination polymers have been characterized by elemental analysis, IR spectra, and thermogravimetric analysis and structures have been proposed leading to coordination of metal through S alone as well as N and S both. Thermal stability of the polymers has also been discussed.     

Magnetic properties and structure of a new one-dimensional azido-bridged nickel(II) coordination polymer

A new one-dimensional nickel(II) coordination polymer with azido-bridge, [Ni(dpa)(N₃)₂] · H₂O 1 (where dpa is the 2,2′-dipyridylamine ligand) has been synthesized and crystal structure was determined by single-crystal X-ray diffraction. Complex 1 exhibits a zig-zag chain structural arrangement, and the hexa-coordinated Ni(II) ion exhibits a distorted octahedral coordination sphere. The chains topologies are built via three EO and one EE azido bridges. The study of the magnetic properties reveals dominating antiferromagnetic interactions between Ni(II) ions through the EE bridges.     

Hydrothermal synthesis of two new zinc coordination polymers with mixed ligands

The hydrothermal reactions of zinc acetate with 1,2,4,5-benzenetetracarboxylic anhydride (btc) and 4,4^′-bipyridine (4,4^′-bpy) for [Zn₂(4,4^′-bpy)(btc)(H₂O)₂]_n·2nH₂O (1) or imidazole (imi) for [Zn₂(imi)₄(btc)(H₂O)₂]_n (2) in the molar ratio of 1:1:1:2000 at 170 °C for five days led to the formation of colorless crystals of 1 and 2. The btc ligand acts as a four-dentate bridging ligand in both compounds to link up zinc atoms into linear chain architectures. In 1, the linear chain subpolymers are further interlinked into a lamellar framework via 4,4^′-bpy ligands. Finally, both 1 and 2 are extended into three-dimensional framework via hydrogen bonding.     

Three cobalt (II) complexes with triethylenetetraaminehexaacetic acid: From binuclear complex to 3d-4f coordination polymers

The cobalt(II)–lanthanide(III) heteronuclear complexes [Ln(H₂O)₄Co₂(TTHA)(SCN)₂]·H₃O⁺ (H₆TTHA = triethylenetetraaminehexaacetic acid, Ln = La(2), Ce(3)) have been synthesized based on a binuclear building block of [Co₂(H₂TTHA)(H₂O)₂] in [Co₂(H₂TTHA)(H₂O)₂]·4H₂O (1). Single-crystal structures show that complex 1 is a binuclear complex, containing the [Co₂(H₂TTHA)(H₂O)₂] unit as a useful building block. Adding the La^3 + and Ce^3 + ions to this synthesis system, two new 3d-4f mixed complexes 2 and 3 were obtained. Complexes 2 and 3 show 3D framework, comprising an infinite 1D (one-dimensional) chain based on heterometallic Ln₂Co₂ (Ln = La(2), Ce(3)). Further investigations such as IR spectra, UV–vis spectra, TGA, XRD and magnetic properties were studied.     

Hydrothermal synthesis and characterization of ternary lanthanide-2,2′-bipyridine-3,3′-dicarboxylate coordination polymers

Two lanthanide coordination polymers, [{Ln₂(bpdc)₃(phen)₂(H₂O)₂} · (H₂O)₆]_n (Ln = Dy (1); Ho (2)) were obtained from 2,2′-bipyridine-3,3′-dicarboxylic acid (H₂bpdc), 1,10-phenanthroline (phen) and corresponding lanthanide oxides by hydrothermal synthesis. Polymers 1–2 are found to be isostructural. Single-crystal X-ray diffraction shows that 1–2 are all one-dimensional zigzag chain structures and extend to two-dimensional networks through π–π interactions and hydrogen bonds. Thermogravimetric analysis of 1–2 displays a considerable thermal stability. The variable-temperature magnetic susceptibility of both compounds was measured. Photoluminescence measurement indicates that 1 is a strong yellow emitter.     

Selective adenine/cytosine cations in one-dimensional coordination polymers of manganese (II) and copper (II) 2,3-pyridinedicarboxylates

One-dimensional coordination polymer {[1H,9H-ade]₂[MnL₂]?4H₂O}_n (1) and {[1H,3H-cyt]₂[CuL₂]?6H₂O}_n (2) (ade = adenine, cyt = cytosine, L = dianion of 2,3-pyridinedicarboxylic acid) are selectively synthesized and variable-temperature magnetic susceptibility measurements revealed weak antiferromagnetic interactions within the chains of 1 and 2 (J = ? 0.29 cm^? 1 for 1 and J = ?0.03 cm^? 1 for 2, according to the ? 2J_ijS_iS_j HDvV Hamiltonian formalism).     

一维链状均苯三酸锌配合物[Zn_3(BTC)_3(H_2O)_(12)]_n的水热合成及晶体结构研究

以Zn(CH3COO)2和均苯三酸(1,3,5-苯三酸)为原料,采用水热法合成了一维链状均苯三酸锌配合物[Zn3-(BTC)3(H2O)12]n,利用元素分析、X射线单晶衍射对其结构进行了表征。该配合物属于单斜晶系,C2空间群,a=17.424(5)nm,b=12.919(5)nm,c=6.577(5)nm,β=111.968(5)°,V=1.373 0(12)nm3,Z=2,Dc=1.999 g/cm3,μ=2.707 mm-1,F(000)=840,R1=0.031 5,wR2=0.078 9。     

A novel one-dimensional nickel(II) complex with a hydrogen-bond-link

A novel compound [Ni(L)(H₂O)₂]_0.5[Ni(L)(WO₄)₂]_0.5·4H₂O (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0^1.18,0^7.12]docosane) has been structurally and magnetically characterized. The nickel(II) ions are shown to be in distorted octahedral environments with secondary amines of macrocycles in which two trans water molecules and two trans tungstate ions are assembled around each metal center. Two nickel(II) complexes are connected into a one-dimensional chain via hydrogen bonds. The magnetic susceptibility measurement for 1 indicates weak antiferromagnetic interaction (J=−1.01(2) cm⁻¹; H=−JΣS_i·S_i+1) between the S=1 nickel(II) paramagnetic centers.     

水杨醛缩4-氨基安替比林与Zn(II),Ni(II),Co(II)配合物的合成和表征

以水杨醛、4-氨基安替比林和醋酸盐为原料,在酸性条件下,以乙醇为溶剂,合成了水杨醛缩4-氨基安替比林希夫碱及其配合物。考察了反应时间、温度、原料配比对该合成的影响。结果表明,反应的最佳条件为:水杨醛∶4-氨基安替比林∶醋酸盐(摩尔比)=1∶1∶1,在80℃条件下反应5 h,产率可达80%。通过红外和紫外光谱进行表征,研究了他们的性质。     

NMR-based structural characterization of common aromatic poly(amic acid) polymers

Polymer Bulletin - Polyamic acid (PAA) has been widely synthesized as the precursor of polyimide for over 50 years. PAA has had recent attention when used as a final polymer in a variety...     

Microporous coordination polymers of cobalt(II) and manganese(II) 2,6-naphthalenedicarboxylate: preparations, structures and gas sorptive and magnetic properties

Two isostructural coordination polymers M₃(NDC)₃(DMF)₄ (M = Co (1), Mn (2); H₂NDC = 2,6-naphthalenedicarboxylic acid; DMF = N,N′-dimethylformamide) were prepared through conventional and microwave-assisted solvothermal methods. Single crystal X-ray analysis indicated that both complexes crystallized in the monoclinic system with space group C2/c. Powder X-ray diffraction (PXRD) patterns of the bulk samples for the two complexes obtained from microwave-assisted solvothermal syntheses matched well with the simulated ones from the single crystal data as well as the ones prepared by conventional solvothermal method. These microporous cobalt(II) and manganese(II) coordination polymers undergo reversible structural change upon desolvating, giving stable microporous frameworks containing unsaturated metal sites, and resolvating. The desolvated complexes showed different nitrogen gas adsorption capabilities but very close hydrogen adsorption behaviors. Variable-temperature magnetic susceptibilities of 1 and 2 revealed the weak antiferromagnetic coupling between the adjacent metal ions bridged by carboxylate.     

Novel two-dimensional Co(II) and Cd(II) coordination polymers with intriguing net topologies

Three new two-dimensional coordination polymers were constructed from 2,6-bis(imidazole-1-yl)pyridine (2.6-bip), terephthalic acid (1,4-bdcH₂), and M(NO₃)∙nH₂O (M = Co, Cd). [M(2,6-bip)(1,4-bdc)] (1: M = Co; 2: M = Cd) were prepared under hydrothermal condition, whereas [Cd(2,6-bip)(1,4-bdc)∙xDMF] (3) was obtained under solvothermal condition in DMF solvent. Single-crystal X-ray analyses revealed the first example of a 2D 4-connected net of 6⁶ topology in 1 and 2 and a rare 2D 4,5-connected net of 4,5 L20 topology in 3. All these complexes were thermally robust and emissive in solid-states. This work confirmed the versatility of using hingelike 2,6-bip as a linker and the importance of solvent effect in the process of framework formation.     

Hydrothermal synthesis and characterization of a copper(I) halide coordination polymer with isonicotinic acid (IN) ligand as a template possessing three-dimensional supramolecular network structure

The title compound [CuBr(IN)]_n 1 was hydrothermally synthesized from a simple reaction of CuBr₂–IN–KBr–NaOH–H₂O. X-ray analysis revealed that it is a new example containing extended one-dimensional staircase chain in copper(I) halide family. Its structure can be better described as a three-dimensional supramolecular network assembled via a combination of coordinate–covalent bonds and intermolecular hydrogen bonds. Moreover, compound 1 was characterized by elemental analysis, IR spectrum and TGA analysis.     

Two cobalt(II) coordination polymers based on carboxylate ligand: Preparation,crystal structures and magnetic properties

Two new coordination polymers, [Co₂(L)_1.5(OH)(H₂O)₂]·2H₂O (1) and [CoL(bpp)] (2) (H₂L = 2,5-dibenzoylterephthalic acid and bpp = 1,3-bis(4-pyridyl)propane), have been synthesized and characterized by elemental analyses, IR spectra, and thermogravimetric analyses. Their structures were determined by single crystal X-ray diffraction analyses. Complex 1 exhibits a 3D framework assembled from tetra-nuclear cobalt-oxygen bridged by carboxylic O atoms with a (4¹²·6³) topology. Complex 2 possesses a 2D layered structure which extends into a 3D architecture via C–H···π interaction between propane proton and the phenyl ring or pyridine ring of an adjacent sheets. Furthermore, the magnetic properties of them are discussed.