Syntheses and structural characterization of trivalent lanthanide complexes of p-sulfonatothiacalix[4]arene

The X-ray crystallographic studies are reported for the water-soluble trivalent lanthanide complexes of the macrocyclic p-sulfonatothiacalix[4]arene [Gd(H₂O)₆((CH₃)₂SO)(p-sulfonatothiacalix[4]arene)]·H₃O⁺·5H₂O (1) and Na[Nd(H₂O)₆((CH₃)₂SO)(p-sulfonatothiacalix[4]arene)]·3H₂O (2). The complexes are isostructural and belong to monoclinic system, C2/m space group. The Ln³⁺ metal ion is coordinated by the thiacalixarene ligand via the sulfonato group, and also ligated by an oxygen atom of a dimethyl sulfoxide (DMSO) molecule that occupies the cavity of the thiacalixarene and six aqua ligands. The thiacalixarenes are linked by the coordinated water molecules through hydrogen bonding to form a 2D polymer. The p-sulfonatothiacalixarenes maintain the clay-like bi-layer structure in the coordination network.     

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.     

Four Coordination Polymers Assembled with a New Biscarboxyl-functionalized Schiff Base Ligand

Based on a new biscarboxyl-functionalized Schiff base ligand 1,2-cyclohexanediamino-N,N'-bis[3-methoxyl-5-(p-carboxyl-phenylazo)] salicylidene(H₄L), four polymers,[(CH₃)₂NH₂]₂·[Mn₃(L)₂(H₂O)₄]·2DMF(CP1),[Fe₂(L)(H₂O)(DMF)](CP2),[(CH₃)₂NH₂]·[Cu(HL)]·H₂O(CP3) and[Ni₂(L)(teta)]·2DMF·H₂O(CP4), have been synthesized(teta=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). In CP1, both of the internal[N₂O₂] pocket and the external carboxylate groups of L^4- anion are ligated by Mn²⁺ ions, and the structure displays a layer. In CP2, the Fe²⁺ cations are linked by L^4- anions to form a binuclear double chain. CP3 displays a[Cu₂(HL)₂] dimer. In CP4, the Ni²⁺ ions are connected by L^4- anions to form a chain. The structures are further linked by hydrogen bonds to form 2D or 3D supramolecular architectures, respectively. CP1 exhibits adsorption ability to three organic dyes.     

New Tetraazamacrocyclic Ligand with Neutral Pendent Groups 1,4,7,10-tetrakis (2-cyanoethyl)-l,4,7,10-tetraazacyclododecane (L) and Its Cobalt (Ⅱ), Nickel (Ⅱ) and Copper (Ⅱ) Complexes:Synthesis,Structural Characterization and Antitumor Activities

A new tetraazamacrocyclic ligand (L) with four neutral 2-cyanoethyl pendent groups and its divalent transition-metal complexes:[Co(L)(NO₃)]NO₃·H₂O (1),[Ni(L)(NO₃)]NO₃·3H₂O (2) and[Cu(L)(H₂O)](NO₃)₂ (3) have been synthesized. The crystal structures of (1) and (3) have been determined by X-ray analysis. In complex (1) the cobalt atom is coordinated by four nitrogen atoms and two oxygen atoms of a nitrate anion, which define a distorted octahedron. The other nitrate ion lies in the lattice as a counter ion.     

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^-.     

Molecular, supramolecular structure and catalytic activity of transition metal complexes of phenoxy acetic acid derivatives

Six mononuclear complexes [M(L₁)₂(H₂O)₄] (M = Co(II), 1a and M = Mn(II), 1b), [Cu(L₁)₂(H₂O)₂] (1c), [Cu(L₁)₂(H₂O)(Py)₂] (1d), [Cu(L₃)(H₂O)Cl] · H₂O (3a) and [Co(Sal)(H₂O)(Py)₃] · 2ClO₄ · H₂O (3b) of phenoxyacetic acid derivatives and Schiff base were determined by single crystal X-ray diffraction. The Co(II) (1a) and Mn(II) (1b) complexes are isomorphous. X-ray crystal structural analyses reveal that these coordination complexes form polymeric structure via formation of different types of hydrogen bonding and π-stacking interactions in solid. Thermal analysis along with the powder X-ray diffraction data of these complexes shows the importance of the coordinated and/or crystal water molecules in stabilizing the MOF structure. Complexes 1a, 1c, 3a show marginal catalytic activity in the oxidation of olefins to epoxides in the presence of i-butyraldehyde and molecular oxygen.     

Copper(II) complexes with the N,N,O-tridentate ligand 6-amino-5-formyl-1,3-dimethyluracilato-(N6)-benzoylhydrazone: synthesis, spectral and XRD studies

From reactions between different Cu(II) salts and the Schiff base 6-amino-5-formyl-1,3-dimethyluracil-benzoylhydrazone (H₂BEZDO) in alcohol, six new copper complexes with simplified formulas [Cu(HBEZDO)(H₂O)(MeOH)]NO₃ (1), [CuCl(HBEZDO)(DMF)] (2), [CuBr(HBEZDO)]·2H₂O (3), CuBr(HBEZDO) (4), Cu(ClO₄)(HBEZDO)·H₂O (5), and Cu(SO₄)_1/2(HBEZDO)·1 H₂O (6) were isolated. The structures of compounds 1, 2 and 3 have been established by means of XRD diffraction methods. In the three compounds, the Schiff base acts as a tridentate monodeprotonated ligand through the N(6), N(51) and O(52) atoms, making two five- and six-membered chelate rings. In the structure of 1 and 2, the solvent molecules are coordinated giving square-based pyramidal environments, with the basal plane completed by a MeOH (1) or Cl (2) and the apical positions occupied by the oxygen atom of a water (1) or a DMF molecule (2). The molecular unit of the complex [CuBr(HBEZDO)]·2H₂O (3) is defined by a square-plane containing the three donor atoms of the organic ligand and a bromide ligand (Cu–Br 2.384 Å), but there is a stronger tetragonally elongated pyramidal geometry around the metal, the apical position of the polyhedron being occupied by a weakly bound-to-copper bromine atom (3.086 Å) of a neighbouring molecule. This fact gives the appearance of an apparent dimer with very asymmetric bromine bridges, in which there are no exchange interactions between metal centres. Also, infrared, magnetic and EPR data of the isolated complexes are reported.     

Synthesis, structure and properties of delocalized transition metal chelates: Diazoketiminato chelates of Co(III) and Pt(II)

The reactions of HL 1 [where HL is 1N-(2-pyridyl-2-methyl)-2-arylazoaniline and is formulated as ArN = NC₆H₄N(H)(CH₂C₅H₄N); Ar = C₆H₅ (for HL¹) or p-MeC₆H₄ (for HL²) or p-ClC₆H₄ (for HL³)] with K₂PtCl₄ and Co(ClO₄)₃ · 6H₂O afforded the (L)PtCl and [(L)₂Co]ClO₄ complexes, respectively. The HL ligands bind the platinum(II) and cobalt(III) centres in a tridentate (N,N,N) fashion, forming new diazoketiminato chelates upon dissociating the amino proton. The X-ray structures of (L³)PtCl and [(L³)₂Co]ClO₄ were determined. Redox properties of the new complexes have been examined.     

Synthesis, reaction and structure of a series of chromium(III) complexes containing oxalate ligand

A series of chromium(III) complexes [Cr(bipy)(HC₂O₄)₂]Cl·3H₂O (1), [Cr(phen)(HC₂O₄)₂]Cl·3H₂O (2), [Cr(phen)₂(C₂O₄)]ClO₄ (3), [Cr₂(bipy)₄(C₂O₄)](SO₄)·(bipy)_0.5·H₂O (4) and [Mn(phen)₂(H₂O)₂]₂[Cr(phen)(C₂O₄)₂]₃ClO₄·14H₂O (5) were synthesized (bipy=4,4′-bipyridine, phen=1,10-phenanthroline), while the crystal structures of 1 and 3–5 have been determined by X-ray analysis. 1 and 3 are mononuclear complexes, 4 contains binuclear chromium(III) ions and 5 is a 3D supromolecule formed by complicated hydrogen bonding. 1–3 are potential molecular bricks of chromium(III) building blocks for synthesis heterometallic complexes. When we use these molecular bricks as ligands to react with other metal salts, unexpected complexes 4 and 5 are isolated in water solution. The synthesis conditions and reaction results are also discussed.     

Neutral pyridylmethylamide ligands and their mononuclear copper(II) complexes

Mononuclear copper(II) complexes of a family of pyridylmethylamide ligands HL, HL^Me, HL^Ph, HL^Me3 and HL^Ph3, [HL = N-(2-pyridylmethyl)acetamide; HL^Me = N-(2-pyridylmethyl)propionamide; HL^Ph = 2-phenyl-N-(2-pyridylmethyl)acetamide; HL^Me3 = 2,2-dimethyl-N-(2-pyridylmethyl)propionamide; HL^Ph3 = 2,2,2-triphenyl-N-(2-pyridylmethyl)acetamide], were synthesized and characterized. The reaction of copper(II) salts with the pyridylmethylamide ligands yields complexes [Cu(HL)₂(OTf)₂] (1), [Cu(HL^Me)₂](ClO₄)₂ (2), [Cu(HL)₂Cl]₂[CuCl₄] (3), [Cu(HL^Me3)₂(THF)](OTf)₂ (4), [Cu(HL^Me3)₂(H₂O)](ClO₄)₂ (5a and 5b), [Cu(HL^Ph3)₂(H₂O)](ClO₄)₂ (6), [Cu(HL)(2,2′-bipy)(H₂O)](ClO₄)₂ (7), and [Cu(HL^Ph)(2,2′-bipy)(H₂O)](ClO₄)₂ (8). All complexes were fully characterized, and the X-ray structures vary from four-coordinate square-planar, to five-coordinate square-pyramidal or trigonal-bipyramidal. The neutral ligands coordinate via the pyridyl N atom and carbonyl O atom in a bidentate fashion. The spectroscopic properties are typical of mononuclear copper(II) species with similar ligand sets, and are consistent their X-ray structures.     

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。     

Crystal Structure and Photoluminescence Properties of Two Barium(Ⅱ) MOFs

In this article, two Ba(Ⅱ) metal-organic frameworks(MOFs), {[Ba(BPS)(H₂O)₂]·H₂O}_n(1) and[Ba(BPS)(H₂O)₂]_n(2)(H₂BPS=4,4'-bibenzoic acid-2,2'-sulfone), were synthesized and characterized. X-Ray crystal structural analyses reveal that compounds 1 and 2 have different structures, which is probably related to different coordination modes of ligand in compounds 1 and 2. It is remarkable that compounds 1 and 2 both show excellent thermal stability. The solid-state emission spectra reveal that compounds 1 and 2 both present strong luminescence emission bands at room temperature.     

两个基于氢键构筑的超分子镁配合物的合成、 晶体结构及荧光性质

以5,6-苯并咪唑二酸(H₃bidc)为有机配体, 在水热条件下通过控制反应温度得到了2个镁配合物[Mg(Hbidc)(H₂O)₄](1) 和 [Mg(Hbidc)(H₂O)₅]·4H₂O(2). 通过单晶及粉末X 射线衍射、 红外光谱、 元素分析和热重分析对配合物进行了表征. 结果表明, 配合物1和2均为单核分子, 分别以不同的堆积方式通过氢键构筑成三维超分子结构. 值得注意的是, 配合物2的结构中捕获了由氢键连接的环状四聚体水簇(H₂O)₄. 配合物1和2的电荷布居分析结果与晶体结构的讨论一致. 此外, 固体荧光分析表明, 配合物1和2在室温下具有较强的蓝光发射.     

Two New Cadmium Metal-organic Frameworks Based on a Mixed-donor Ligand

The self-assembly of a prominent mixed-donor ligand, 5-[4-(1H-tetrazolyl)phen]isophthalic acid(H₃TZPI), with a Cd²⁺ center generates two new metal-organic frameworks:[Cd(H₂TZPI)₂(H₂O)₂]_n(JUC-163) and[Cd₂(TZPI)(μ₃-OH)(H₂O)₂]·H₂O·DMF(JUC-164). The two complexes demonstrate different structures for the ligand’s different coordination modes and configurations. JUC-163 shows a 2D layer structure and further forms into a 3D supramolecular framework by noncovalent interactions(C-H…O, O-H…N and π…π interactions), whereas JUC-164 exhibits a fascinating 3D framework for the outstanding coordination modes and configurations of the ligand, which are fit for the complex structure. And also, the factor of different cadmium salts(chloride and nitrate) which are used in synthesis progress is worth to notice for the construction of the two distinct structures. The luminescent properties of these metal-organic frameworks were also investigated.     

Thermal decomposition study on mixed ligand thymine complexes of divalent nickel(II) with dianions of some dicarboxylic acids

Thermal decomposition of mixed ligand thymine (2,4-dihydroxy-5-methylpyrimidine) complexes of divalent Ni(II) with aspartate, glutamate and ADA (N-2-acetamido)iminodiacetate dianions was monitored by TG, DTG and DTA analysis in static atmosphere of air. The decomposition course and steps of complexes [Ni(C₅H₆N₂O₂)(C₄H₅NO₄)²⁻(H₂O)₂]·H₂O, [Ni(C₅H₆N₂O₂)(C₅H₇NO₄)²⁻(H₂O)₂]·H₂O and [Ni(C₅H₆N₂O₂)(C₆H₈N₂O₅)²⁻(H₂O)₂]·1.5H₂O were analyzed. The final decomposition products are found to be the corresponding metal oxides. The kinetic parameters namely, activation energy (E*), enthalpy (ΔH*), entropy (ΔS*) and free energy change of decomposition (ΔG*) are calculated from the TG curves using Coats–Redfern and Horowitz–Metzger equations. The stability order found for these complexes follows the trend aspartate > ADA > glutamate.     

Novel One-dimensional Cyano-bridged Chain Molecular-based Magnet[Ln(DMF)4(H2O)2Mn(CN)6·H2O]n:Crystal Structure,Long-range Magnetic Ordering,High Tc and Strong Coercive Behavior

There has been great interest in the study of the magnetic properties of molecular-based compounds^[1,2]. In the present work, we employed N,N-dimethylformide (DMF) as a hybrid ligand to synthesize a new family of cyano-bridged complexes contain rare earth and Manganese:[Ln(DMF)₄(H₂O)₂Mn(CN)₆·H₂O]_n (abbreviated as LnMn, Ln=Sm, Eu, Gd, Tb, Dy, Er) and the crystal data of former three complexes has been obtained, which display a remarkable variety of magnetochemical behavior and a rich structural chemistry.     

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.     

铜配合物修饰的Dawson型钨磷酸盐的合成、晶体结构和催化性能

在水热条件下,Cu(Ⅱ)-H₂biim配合物与Dawson型钨磷酸盐构筑了1个无机-有机杂化化合物[Cu(H₂biim)₂(H₂O)][{Cu(H₂biim)₂}₂(P₂W₁₈O₆₂)]·11H₂O(1)(H₂biim=2,2'-联咪唑)。 通过单晶X射线衍射、红外光谱(IR)、X射线粉末衍射(XRD)、元素分析、电化学分析等技术手段对其进行了表征。 结构分析表明,在化合物1分子中,[P₂W₁₈O₆₂]^6-单元作为双齿配体与2个Cu²⁺离子配位形成双支撑的杂多阴离子[{Cu(H₂biim)₂}₂(P₂W₁₈O₆₂)]^2-,在其外部有1个游离的[Cu(H₂biim)₂(H₂O)]²⁺ 和11个H₂O分子。 H₂biim分子与杂多阴离子/H₂O分子间存在氢键,通过氢键、静电和π-π堆积作用,进一步构成具有3D结构的晶体材料。 该晶体化合物对H₂O₂和NaNO₂的还原具有良好的电催化作用;同时,作为酸催化剂用于合成环己酮乙二醇缩酮反应,催化活性高,可重复使用。     

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.     

(3,3)-Connected Three-dimentional Supramolecular Metal Organic Polyhedral Based on Nanometresized Ligand with Magnetism Properties

A three-dimentinal metal organic framework[Co₂(L)Cl(DMF)₂(H₂O)](DMF)₃(H₂O)₃ based on the nanometresized ligand 4,4',4"-[1,3,5-benzenetriyltris(carbonylimino)]trisbenzoic acid was synthesized, and characterized by means of single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, thermogravimetry analysis and magnetism. This obtained structure can be considered to be constructed from 2D layer, which displays the topology of hbc based on Co₂(COO)₃ secondary building unit, and further to be linked into a 3D supramolecular architecture by N-H…O hydrogen bonds. The magnetism of the complex was carried out, which shows ferromagnetic exchange interactions.