Solvothermal syntheses and crystal structures of two metal coordination polymers with double-chain structures

Two polymeric complexes, [Cu₂(btec)(phen)₂]_n·(H₂O)_n (1) and [Cd₄(btec)₂(phen)₄(H₂O)₄]_n (2) (H₄btec=1,2,4,5-benzenetetracarboxylic acid; PHEN=1,10-phenanthroline), were synthesized by solvothermal reactions at 140 °C. Both complex 1 and 2 possess infinite double-chain structures, in which each Cu(II) center has a tetrahedral configuration and the Cd(II) centers adopt triangular prismatic and square-based pyramidal configurations simultaneously. The inter-chain face to face π–π interactions among the aromatic rings of phen and the hydrogen bond interactions between aqua molecules and carboxyl O atoms result in 3-D networks in the two complexes. The ESR spectra study of complex 1 shows that there is negligibly small long-range super-exchange interactions between the Cu(II) atoms via benzenecarboxylate bridging.     

Synthesis, crystal structure and magnetic behavior of two cobalt coordination polymers with 1,2-bis(1,2,4-triazol-1-yl)ethane and dicyanamide

Two cobalt(II) coordination polymers formed from bte (bte = 1,2-bis(1,2,4-triazol-1-yl)ethane), namely [Co(bte)₂(dca)₂]_n (1) and {[Co(bte)(dca)₂] · H₂O}_n (2), have been synthesized and characterized by elementary analyses, IR, thermogravimetric analyses, X-ray diffraction analyses and magnetic measurements. Compound 1 is a double-chain with Co(II) centers bridged by bte, containing metallocycles of [Co₂(bte)₂] and trans dca as termination ligands. In 2, each Co(II) center is bonded by two bridging bte ligands and four dca as μ-1,5-dca in different orientations in the 3D network.     

Three interpenetrated frameworks constructed by long flexible N,N′-bipyridyl and dicarboxylate ligands

Three interpenetrated polymeric networks, {[Co(bpp)(OH-BDC)] · H₂O}_n (1) [Ni(bpp)_1.5(H₂O)(OH-BDC)]_n (2) and {[Cd(bpp)(H₂O)(OH-BDC)] · 2H₂O}_n (3), have been prepared by hydrothermal reactions of 1,3-bis(4-pyridyl)propane (bpp), 5-hydroxyisophthalic acid (OH-H₂BDC), with Co(NO₃)₂ · 6H₂O, Ni(NO₃)₂ · 6H₂O and Cd(NO₃)₂ · 4H₂O, respectively. Single-crystal X-ray diffraction analyses reveal that the three compounds all exhibit interpenetrated but entirely different structures. Compound 1 is a fourfold interpenetrated adamantanoid structure with water molecules as space fillers, in which bpp adopts a TG conformation (T = trans, G = gauche). Compound 2 is an interdigitated structure from the interpenetrated long arms of one-dimensional molecular ladders, while bpp in 2 adopts both TT and TG conformations. Compound 3 is a twofold interpenetrated three-dimensional network from a one-dimensional metal-carboxylate chain bridged by TG conformational bpp. The hydrogen bonding interactions in 1–3 further stabilize the whole structural frameworks and play critical roles in their constructions.     

Hydrothermal synthesis, crystal structures and luminescent properties of two new Ln(III)–succinate (Ln=Eu, Tb) complexes exhibiting three dimensional networks

Two new coordination polymers, [Eu₂(L)₃(H₂O)₂]_n 1 and {[Tb₂(L)₃(H₂O)₂]·H₂O}_n 2, (H₂L=succinic acid) have been synthesized by the reaction of H₂L with nitrate salts of Eu(III) or Tb(III) under hydrothermal conditions. The X-ray diffraction analysis reveals that the two complexes are constructed by L bridging the chains of edge-sharing EuO₈(H₂O) or TbO₈(H₂O) polyhedra to form 3D network structure. 1 and 2 possess different topological structures due to the difference in the conformations of L. The solid photoluminescence of 1 and 2 was also investigated in room temperature.     

以氧化锌为锌源的手性金属-有机骨架的合成及其用于联糠醛外消旋体的选择性吸附

通过使用氧化锌代替传统的金属无机盐为锌源,制备了手性金属-有机骨架（CMOF）[Zn（L-mal）（H₂O）₂]_n并对其手性分离性能进行了考察。将ZnO和L-苹果酸按物质的量之比1：1溶于水中,在室温下静置24 h即可得到[Zn（L-mal）（H₂O）₂]_n。以100 mg[Zn（L-mal）（H₂O）₂]_n为吸附剂,将250 μL 1 g/L的联糠醛外消旋体加入其中,并以4.5 mL异丙醇和1 mL甲醇为萃取剂和洗脱剂进行选择性吸附实验,最终滤液使用高效液相色谱仪（HPLC）进行分析。结果表明,[Zn（L-mal）（H₂O）₂]_n对R-联糠醛具有较好的选择性吸附,其对映体过量（ee）值为20%。该工作为CMOF的绿色制备提供了一定的方法和经验并拓展了其在手性分离领域的应用。     

Ion size dominated 1D and 2D Salen lanthanide coordination complexes and their luminescence

Lewis acid/base addition between Ln(NO₃)₃ · 6H₂O (Ln = Pr, Nd, Sm, Eu, Tb and Lu) and H₂salen [H₂salen = N,N′-ethylenebis(salicylideneimine)] gives rise to an array of coordination polymeric structures. Crystal structural analysis reveals that Salen effectively functions as a bridging ligand in these compounds. The size of the lanthanide ions controls the structures of these Salen lanthanide complexes. Two representative structures with one dimensional and two dimensional topologies, viz. [Pr(H₂salen)(NO₃)₃(CH₃OH)₂]_n (1) and [Ln(H₂salen)_1.5(NO₃)₃]_n [Ln = Pr (2), Nd (3), Sm (4), Eu (5), Tb (6) and Lu (7)] are reported. Luminescent spectra of complexes 4 and 5 exhibit characteristic metal-centered emission lines. However, the characteristic luminescence of the terbium(III) ion is not observed either in solution or in the solid state of complex 6.     

Two novel lanthanide 1-D chain coordination polymers of pyridinedicarboxylic acids: hydrothermal synthesis, structure and luminescent properties

Two novel lanthanide coordination polymers [Sm(Hdipic)(dipic)(H₂O)₂·4H₂O]_n (1) (H₂dipic=2,6-pyridinedicarboxylic acid) and [Dy(Hdinic)(dinic)(phen)(H₂O)·H₂O]_n (2) (H₂dinic=2,5-pyridinedicarboxylic acid) have been synthesized under hydrothermal condition and characterized by single-crystal X-ray diffraction. The results reveal that both of them form a chain-like one-dimensional structure. The photophysical properties for the two complexes have been also reported. Complex 1 shows the characteristic luminescence of central Sm³⁺ while complex 2 exhibits the particular emission ascribed H₂dinic ligands, which suggest the different energy transfer process takes place.     

Syntheses and X-ray crystal structures of [Co(η-CO3)(NH3)4](NO3)·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O

[Co(η²-CO₃)(NH₃)₄](NO₃)·0.5H₂O and [(NH₃)₃Co(μ-OH)₂(μ-CO₃)Co(NH₃)₃][NO₃]₂·H₂O were prepared by prolonged aerial oxidation of a solution of Co(NO₃)₂·6H₂O and ammonium carbonate in aqueous ammonia. The formation of these side products highlights the richness of the chemistry of these systems and the possibility of by products if methods are not strictly adhered to. The X-ray crystal structures of [Co(η²-CO₃)(NH₃)₄][NO₃]·0.5H₂O and [(NH₃)₃Co(μ-OH)₂(μ-CO₃)Co(NH₃)₃][NO₃]₂·H₂O reveal a monomeric octahedral cobalt center with η²-bound CO₃²⁻ in the former, while the latter consists of a dimeric array where the two cobalt centers are bridged by two OH⁻ and one μ₂-CO₃²⁻ groups with three terminal NH₃ ligands for each Co center. In both complexes extensive hydrogen bonding interactions are evident.     

Structural, spectral and thermal properties of a polymeric nickel(II) complex containing two-dimensional network

The structure of the complex [Ni(hmt)(NCS)₂(H₂O)₂]_n, assembled by hexamethylenetetramine (hmt) and octahedral Ni(II), is reported. Crystal data: Fw 351.07, a=9.885(10) Å, b=12.06(1) Å, c=12.505(8) Å, β=114.41(4)°, V=1357(1) ų, Z=4, space group=C2/c, T=173 K, λ(Mo−K)=0.71070 Å, ρ_calc=1.718 gcm⁻¹, μ=17.44 cm⁻¹, R=0.099, Rw=0.145. The tetrahedral assembling template effect of the hmt molecule is completed by two coordination bonds and two hydrogen interactions. The UV–vis absorption spectrum of this complex [Ni(hmt)(NCS)₂(H₂O)₂]_n with a two-dimensional network is determined in the range of 5000–35000 cm⁻¹ at room temperature. The observed spectrum is discussed and explained perfectly by the scaling radial theory proposed by us. The two-dimensional structure has no apparent effects on the d–d transitions of the central Ni(II) ion. The IR spectrum and the GT curve of the complex were also measured and clearly reflect its structural properties.     

Syntheses, crystal structures and magnetic properties of Ni(II)–2,4-pyridine-dicarboxylates

Two new complexes [Ni(pydc)(H₂O)₂]_n (1) and [Ni₂(pydc)₂(H₂O)₅]_n (2) (H₂pydc = 2,4-pyridinedicarboxylic acid) have been obtained by hydrothermal synthetic method and characterized by single crystal X-ray analysis. In 1 six-coordinate Ni(II) ions are coordinated by pydc ligands to form 2-D layer structures; while in 2 six-coordinate Ni(II) ions are only connected into 1-D zigzag chains constructed by dinuclear nickel units. Although the coordination geometries around Ni(II) centers in both complexes are similar, their structure topologies are greatly tuned by coordination modes of pydc. Variable temperature magnetic susceptibility studies have shown that both compounds 1 and 2 may display antiferromagnetic coupling between paramagnetic metal centers mediated by bridging carboxylate groups.     

Syntheses and structural characterization of transition metal(II) coordination polymers containing 4,4′-dipyridyldisulfide

The reactions of Zn(NO₃)₂ · 6H₂O and FeSO₄ · 7H₂O with 4-PDS (4-PDS = 4,4′-dipyridyldisulfide) and NH₄SCN in CH₃OH afforded the complexes [Zn(NCS)₂(4-PDS)]_n (1) and [Fe(NCS)₂(4-PDS)₂ · 4H₂O]_n (2), respectively, while the reaction of CoCl₂ · 6H₂O with 4-PDS in CH₃OH gave the complex {[Co(4-PDS)₂][Cl]₂ · 2CH₃OH}_n, (3). These complexes have been characterized by spectroscopic methods and their structures determined by X-ray crystallography. The 4-PDS ligands in 1 are coordinated to the metal centers through the nitrogen atoms to form 1-D zigzag-chains, and the distorted tetrahedral coordination geometry at each zinc center is completed by a pair of N-bonded thiocyanate ligands. Compound 2 has a 1-D channel-chain structure and each octahedral Fe(II) metal center is coordinated by four 4-PDS ligands and two trans N-bonded thiocyanate ligands. Weak SS interactions in complex 1 link the 1-D chains into 2-D molecular sheets. In complex 2, the channel chains are interlinked through SS interactions to form molecular sheets, which interpenetrate through the SS interactions to form 3-D structures with large cavities that are occupied by the water molecules. Compound 3 also has a 1-D channel-chain structure with each square-planar Co(II) metal center coordinated by four 4-PDS ligands. Multiple C–HCl hydrogen bonds and SO interactions in 3 link the 1-D chains into 2-D structures.     

Zn(II) complexes with pyridine derived N6 and N8 donor azamacrocyclic ligands

A novel N6 macrocyclic ligand, L¹ (2,8,14,20-tetramethyl-3,7,15,19,25,26-hexaaza-tricyclo[19.3.1.1^9,13]hexacosa-1(24),9,11,13(26),21(25),22-hexaene), was obtained by reduction of the 2 + 2 condensation product of 2,6-diacetylpyridine and propane-1,3-diamine. Zinc(II) complexes of L¹, of a related N8 macrocycle, L³ (3,6,9,17,20,23,29,30-octaaza-tricyclo[23.3.1.1[11,15]]triaconta-1(28),1,13,15(30),25(29),26-hexaene), similarly prepared by 2 + 2 condensation of 2,6-diformylpyridine and diethylenetriamine and of a tetra N-2-cyanoethyl derivative of a homologue of L¹ prepared from diformyl pyridine and ethane-1,2-diamine, L² (3-[6,14,17-tris-(2-cyano-ethyl)-3,6,14,17,23,24-hexaaza-tricyclo[17.3.1.1^8,12] tetracosa-1(23),8(24),9,11,19,21-hexaen-3-yl]-propionitrile), were prepared. Structures were determined for [ZnL¹](ClO₄)₂ · H₂O, [ZnL²](NO₃)₂ and [Zn₂L³(NO₃)₂](NO₃)₂ · H₂O. The [ZnL¹](ClO₄)₂ · H₂O and [ZnL²](NO₃)₂ complexes present a mononuclear endomacrocyclic structure with the metal in an octahedral distorted environment coordinated by the six donor nitrogen atoms from the macrocyclic backbone while the complex [Zn₂L³(NO₃)₂](NO₃)₂ · H₂O is dinuclear with both metal atoms into the macrocyclic cavity coordinated by four donor nitrogen atoms from the macrocyclic framework and one oxygen atom from one monodentate nitrate anion, in a distorted square pyramidal arrangement.     

Carboxylate-induced Various Structures of Ni(II) Complexes with Fluorescence Sensing and Bifunctional Electrochemical Properties

We synthesized three new Ni(II) coordination polymers [Ni(LXHLPXH2O)2]- H2O(CP1),[Ni(LXNIP)]-2H2O(CP2) and [Ni(LXNDCXH20)2](CP3)[L=N,N′-bis(pyridme-3-yl)thiophene-2,5-dicarboxamide, H2HIP=5-hydroxyisophthalic acid, H2NIP=5-nitroisophthalic acid, H2NDC=2,6-naphthalenedicarboxylie acid] by hydrothermal method, which were characterized by means of infrared spectra(IR), TG analyses, PXRD and single-crystal X-ray diffraction. The CPI is a ID tubular structure based on [Ni-HIP]2 loops and pairs of L ligands. CP2 is a 2D 3,5-connected architecture, which consists of Ni-L linear chains and (Ni-NIP)2 double chains. CP3 is a 2D network, which features 4-connected topology. Solid-state luminescent behaviours of CP-P3 were investigated. The CPI can detect Fe^3+ ions through luminescence quenching. The electrochemical properties of CPI buk-modified carbon paste electrode(CP1-CPE) has also been investigated, which has bifunctional electrocatalytic activity for oxidation of ascorbic acid and reduction of NO2^-.     

Hydrothermal Synthesis,Structure and Property of Transition Metal(Mn,Zn, Cd or Pb) Coordination Frameworks Using Quinoline-8-oxy-acetate Acid and Dicarboxylic Acid as Ligands

Five transition metal coordination compounds, [Mn₂(8-qoac)₂(bdc)(H₂O)₄](1)(8-qoacH=quinoline-8-oxy- acetate acid, H₂bdc=benzene-1,4-dicarboxylic acid), [Zn₄(8-qoac)₄(bdc)₂]_n(2), {[Cd₂(8-qoac)₂(Hip)₂(H₂O)₂]· (H₂O)₄}_n(3)(H₂ip=benzene-1,3-dicarboxylic acid), [Pb₃(8-qoac)₂(bdc)_1.5(H₂O)Cl]_n(4) and [Zn₂(8-qoac)(8-ql)(bdc)]_n (5)(8-Hql=8-hydroxyquinoline), were synthesized by hydrothermal syntheses of metal salts with benzenedicarboxy- lic acid and 8-qoacH. Compound 1 possesses a discrete dimer bridged by bdc^2- ligand. Compound 2 presents a 2D layer network constructed from bdc^2- linkers and 1D infinite ribbons, in which Zn(II) centers are bridged by 8-qoac^- with a tetradentate binding mode. Compound 3 displays a 1D zigzag chain, with adjacent chains further connected via extensive O-H···O hydrogen bonds to generate a 3D supramolecular structure. Compound 4 shows a 3D framework containing trinuclear lead secondary building units and bdc^2- linkers, in which a new coordination mode of 8-qoac^- ligand is observed. In compound 5, Zn(II) ions are simultaneously bridged by 8-qoac^-, 8-ql^- and bdc^2- ligands to form tetranuclear zinc units, which are further interlinked by bdc^2- linkers to yield a 2D wave-like layer. Based on intraligand(IL)(π-π^*) fluorescent emission, compounds 1―5 possess strong purple fluorescent emissions. In addition, the thermal stabilities of compounds 1―5 were studied.     

对苯二甲酸根桥联的双铜(Ⅱ)和双锰(Ⅱ)配合物的合成和长程磁交换作用

合成和表征了4种新型配合物[Cu₂(TPHA)(NO₂-Phen)₁](ClO₁)₂·H₂O、[Cu₂(TPHA)(Me-bpy)₁](ClO₁)₂、[Mn₂(TPHA)(NO₂-Phen)₁](ClO₁)₂·2H₂O和[Mn₂(TPHA)(Me-bpy)₁](ClO₁)₂(TPHA:对苯二甲酸根阴离子;NO₂-Phen:5-硝基-1,10-菲绕啉;Me-bpy:4,4'-二甲基-2,2'-联吡啶).测定了配合物的变温磁化率,并求出了交换积分J分别为-5.04、-6.52、-0.68及-0.73cm^-1.     

2,2′-二甲基-4,4′-联苯二甲酸构筑的两个金属有机骨架

以2,2′-二甲基-4,4′-联苯二甲酸(H2L)为配体,采用溶剂热法合成了2个金属有机骨架:[Ni(μ₂-H₂O)(L)(DMF)(H₂O)]·0.5H₂O(1)和[Cd_2.5(L)(trz)₃(H₂O)₂]·2.5DMF(2)(DMF=N,N-二甲基甲酰胺,Htrz=1,2,4-三氮唑)。借助红外、热重、粉末和单晶X射线衍射对其进行了表征。单晶结构分析表明,1结晶于单斜晶系的P2₁/c空间群,镍离子处在拉长的[NiO₆]八面体中且分别被μ₂-H₂O和L^2-配体连接形成二维sql拓扑网络。2结晶于单斜晶系,C2/m空间群,含有3个不同的镉离子且均为扭曲的八面体构型。3个镉离子被三氮唑负离子以μ_1,2,4-桥连,在ab平面形成二维的kgd层,这些层再被L^2-配体沿c轴支撑形成(4,8)双节点的三维flu拓扑网络。热重分析表明,1和2的网络分别在390和230℃发生分解。     

Coordination Polymers with Bipyridyl Diene and Triene Ligands: Synthesis,Structures and Luminescent Properties

Solvothermal reactions of cadmium salts with bipyridyl diene and triene ligands[1,3-bis((E)-2-(pyridin-4-yl)vinyl)benzene-(1,3-bpeb) and 1,6-bis(4-pyridyl)-1,3,5-hexatriene(bphte)] and one bipyridyl triene ligand[1,6-bis(4-pyridyl)-1,3,5-hexatriene-(bphte)] in the presence of auxiliary carboxylic acids including 2,6-dichlorobenzoic acid(2,6-HDCBA) and 2-naphthal-enecarboxylic acid(2-HNCA) gave rise to four coordination polymers[Cd(bphte)(2,6-DCBA)₂]_n(1), {[Cd(bphte)(2-NCA)₂]·5.8H₂O}_n(2),[Cd₂(1,3-bpeb)₂(2,6-DCBA)₄]_n(3) and {[Cd₄(1,3-bpeb)₄(2-NCA)₇(HCOO)]·     

Cd(Ⅱ)-btec配聚物的合成、结构及光电性能

采用水热法合成了Cd(Ⅱ)配聚物[Cd₃Na₂(btec)_n(1)和{[Cd₃Na₂(btec)₂(H₂O)₂]·4H₂O}_n(2)(H₄btec=1,2,4,5-苯四甲酸). 单晶结构解析结果表明, 配聚物1和2的不对称单元中均包含2种晶体学不等效的Cd(Ⅱ)离子, 分别为六配位和八配位, 均通过btec^4-基团桥连成具有3D无限结构的配聚物. 二者区别在于: 2个配聚物中Na(Ⅰ)离子的配位环境不同, 且配聚物2中存在游离水分子. 表面光伏技术研究结果表明, 2个配聚物在300~500 nm范围内呈现出明显的光伏响应, 表明它们具有一定的光-电转换能力. 对配聚物的表面光电压谱(SPS)与紫外-可见吸收光谱(UV-Vis)进行了关联, 并对配聚物进行了X射线衍射(XRD)和热重(TG)分析.     

Synthesis, spectral properties, crystal structures and antimicrobial effects of copper(II) pyridinecarboxylate adducts with chelating ligands

The reaction of an ethanolic solution of copper(II) pyridinecarboxylates CuX₂·nH₂O (where X is nicotinate (nic) (n=0) or isonicotinate (isonic) (n=4)) with ethylenediamine (en) in a molar ratio of 1:2 lead to the isolation of solid tetragonally distorted octahedral complexes of the type [Cu(en)₂(H₂O)₂]X₂·nH₂O (n=1 for nic; n=0 for isonic). The analogous reaction of CuX₂·nH₂O with diethylenetriamine (dien) in a molar ratio of 1:1 leads to the formation of square-pyramidal pentacoordinated complexes of the type [CuX(dien)(H₂O)]X. On the other hand, the reaction of equimolar quantities of copper(II) nitrate and dien with nicotinate anions (equimolar quantities of pyridinecarboxylic acid and NaOH) in ethanolic solutions gives a solid monomeric complex [Cu(nic)(NO₃)dien)(H₂O)]·H₂O in which the coordination polyhedron around the Cu(II) atom is a (4+1+1) distorted tetragonal bipyramid. Based on the molecular structure the electronic and IR spectra are discussed. Moreover, the results of the quantitative determination of antimicrobial activity of the isonic complexes [Cu(isonic)₂(H₂O)₄], [Cu(en)₂(H₂O)₂](isonic)₂, [Cu(isonic)(dien)(H₂O)](isonic), as well as isonicotinic acid, ethylenediamine and diethylenetriamine alone are discussed.     

Supramolecular formation by aromatic ring stacking and hydrogen bonding in lanthanide(III) complexes with amino acids and 1,10-phenanthroline

[Eu(ABA)(phen)₂(H₂O)₃](ClO₄)₃·3phen·4.5H₂O (1) and [Eu(Val)(phen)₂(H₂O)₃](ClO₄)₃·3phen·2H₂O (2) are two new europium complexes with amino acids and 1,10-phenanthroline (phen=1,10-phenanthroline, ABA=-amino butyl acid, Val= -valine). Their crystal structures were measured by X-ray crystallography. Europium atoms in both complexes are nine-coordinated with bidentate 1,10-phenanthroline and carboxylate anion of amino acids, and water molecules. In the solid state, 1 and 2 have a structure involving aromatic stacking of the coordinated and non-coordinated 1,10-phenanthroline and the oxygen atoms of non-coordinated perchlorate anions being H-bond acceptors connect [Eu(ABA)(phen)₂(H₂O)₃]³⁺·3phen·4.5H₂O or [Eu(Val)(phen)₂(H₂O)₃]³⁺·3phen·2H₂O in their structures. In their interactions, several C–HO bonds play an important role. Owing to their different amino acid ligands and the number of lattice water molecules, there is some difference in their hydrogen bond patterns in 1 and 2. The side chain of -valine is involved in the formation of C–HO bonds. Hydrogen bond and π–π interactions determine the supramolecular formation of three-dimensional net works of both complexes.