Synthesis and characterization of nickel phosphonopropionate hybrid materials

Hydrothermal reaction of nickel acetate with 3-phosphonopropionic acid and 4,4′-bipyridine resulted in two novel phosphonate compounds Ni(HO₃PC₂H₄COO)(4,4′-bpy)(H₂O) · 0.5(4,4′-bpy) (bpy = bipyridine) (I) and Ni(O₃PC₂H₄COOH)(4,4′-bpy)(H₂O)₃ · H₂O (II). Single-crystal X-ray studies reveal that self-assemblies between the ligands and metal ion result in layer (I) and chain (II) structures. Magnetic measurement of I indicate there are ferromagnetic couplings between adjacent Ni²⁺ ions (C = 1.29 cm³ mol⁻¹ K and θ = 2.25 K).     

Two helical one-dimensional copper(II) coordination polymers based on N-(2-hydroxylbenzyl)glycine and N-(2-hydroxylbenzyl)-l-alanine: Syntheses,crystal structures and magnetic studies

Two new helical Cu(II) coordination polymers, [Cu(2,2′-bpy)(Hsgly)]Cl · 2H₂O(H₂sgly = N-(2-hydroxylbenzyl)glycine) (1) and [Cu(2,2′-bpy)(Hsala)](NO₃) · 2H₂O(H₂sala = N-(2-hydroxylbenzyl)-l-alanine) (2) were synthesized. Single crystal X-ray diffraction analysis indicated that both complexes showed helical chains arrangement of Cu(II) centers bridged by carboxyl groups. The magnetic measurements showed complex 1 exhibited ferromagnetic interaction while there was no interaction between the Cu(II) centers in complex 2.     

Synthesis,structure, and properties of dinuclear copper (II) complex with a (H2O)12 cluster

A novel pyrazole complex, namely [Cu₂(4,4′-bpy)₂(2,2′-bpy)(L)₂]·6H₂O has been synthesized under mild condition (4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine). We report the structural evidence in the solid state of discrete water hexamers chair-like conformation. These units were found to act as supramolecular glue in the aggregation of dinuclear copper (II) complex to give a three dimensional network through hydrogen-bonding. The preliminary investigation on the electrochemical property and fluorescence property of the complex are presented.     

Synthesis,structure and magnetic property of a cyanamido bridged trinuclear copper complex

An unusual μ_1,1,3-cyanamido bridged trinuclear copper complex, [(2,2′-bpy)₆Cu₃(NCN)](ClO₄)₄·H₂O (1) (2,2′-bpy = 2,2′-bipyridine), has been synthesized and structurally characterized. Magnetic studies show the existence of large antiferromagnetic coupling between the copper(II) ions.     

An unprecedented 3D honeycomb-shaped cobalt phosphonate containing sixfold helical chains: Synthesis,crystal structure and thermal stability

A new cobalt(II) phosphonate, [Co(aepa)(4,4′-bpy)(H₂O)₂]·2H₂O 1 (H₂aepa = 2-aminoethylphosphonic acid) has been hydrothermally synthesized and characterized by IR, elemental analysis, TGA and single crystal X-ray diffraction analysis. Compound 1 features a 3D alveolate network structure originating from the intertwist of the rare sixfold 1D helical chains, which are assembled from the coordination of the aepa^2? ligands to the cobalt atoms.     

A banana-shaped iron(III)-substituted tungstogermanate containing two types of lacunary polyoxometalate units

A novel polyoxotungstate cluster (H₂en)_2.5H₉[Fe₆Ge₃W₂₄O₉₄(H₂O)₂] · 14H₂O (1) (en = ethylenediamine) has been hydrothermally synthesized and structurally characterized by IR, TGA and single-crystal X-ray diffraction. The polyoxoanion skeleton of 1 is composed of two tri-Fe^III substituted B-α-(Fe₃GeW₉O₄₀) Keggin units connected by an unique hexavacant GeW₆O₂₆ Keggin fragment, leading to the first Fe(III)-containing banana-shaped tungstogermanate. Magnetic measurements of 1 reveal that the exchange interactions within the trimetal clusters are antiferromagnetic.     

Copper-assisted oxidative coupling of primary alcohol and hydrazone: A novel function model of galactose oxidase

Treatments of the MeOH, EtOH and PrOH solutions of 2-acetylpyridine, hydrazine and Cu^II salts (in molar ratio 2:3:2) afforded respectively the complexes, [Cu^II(HL)(Cl)](SO₃CF₃)H₂O (1), [Cu^II(MeL)(H₂O)](ClO₄)₂ (2) and [Cu^II(EtL)](Cl)](ClO₄) (3) (L = bis-(methyl, 2-pyridyl ketone hydrazonyl)methine), in which the ligands, HL, MeL and EtL are formed in situ from oxidative couplings of alcohols and hydrazones.     

Template-assisted assembly of porous lanthanide coordination polymers with 2-aminoterephthalic acid

Porous lanthanide coordination polymers, {[Ln₂(atpt)₃(H₂O)₂] · 0.5(4,4′-bpy)(H₂O)}_n [Ln = Eu(1), Gd(2), Yb(3), H₂atpt = 2-aminoterephthalic acid, 4,4′-bpy = 4,4′-bipyridine] were obtained by hydro-solvothermal reaction, in which 4,4′-bpy acts as template. For the first time the nitrogen atom of an atpt ligand coordinates to metal ions in 1–3. The photophysical properties and thermal stability of 1 were investigated.     

Syntheses,structures and magnetic property of two copper complexes with cyclic dimer and 2D herringbone-like network built from helical motif

Two copper(II) complexes, Cu₂{3,5-(NO₂)₂sal}₂(2,2′-bipy)₂ · 0.5H₂O (1) and [Cu₂{3,5-(NO₂)₂sal}₂(4,4′-bipy)(H₂O)₂]_n (2) (3,5-(NO₂)₂sal = 3,5-dinitrosalicylate, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), were synthesized by hydrothermal reactions and characterized by single crystal X-ray analysis. There are discrete cyclic binuclear structure in 1 and 2D herringbone-like network structure in 2, although bridging ligand 3,5-(NO₂)₂sal in 1 and 2 has same coordination model. Variable temperature magnetic measurement reveals small ferromagnetic interactions in complex 1.     

Syntheses,crystal structures,and magnetic studies of two cobalt(II) coordination polymers based on concurrent ligand extension

An ether bridged tetracarboxylic acid ligand, 5-(3′,4′-Dicarboxylphenoxy)-isophthalic acid (H₄L) was used to construct two Co(II) coordination polymers in presence of different nitrogen donor ligands such as 4,4′-bipyridine (4,4′-bpy) and 4,4′-bis(pyrid-4-yl)biphenyl (bpbp). The products formed under hydrothermal conditions are formulated as [Co₂L(4,4′-bpy)₂(H₂O)₃]_n (1) and {[Co(bpbp)₂(H₂L)]·H₂O}_n (2). The compounds were characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis, and powder X-ray diffraction (PXRD) measurement. Compound 1 shows an intriguing (3,4,5)-connected 3D framework with a point symbol of (4² · 6² · 8²)(4² · 6⁵ · 8³)(6² · 8). Compound 2 is an unusual 3D supramolecular framework generated by the one-dimensional [Co(bpbp)(H₂L)]_n polymer chain. The magnetic properties of compounds 1 and 2 were examined, indicating antiferromagnetic interactions between the cobalt(II) ions in the temperature range of 2–300 K.     

PMMA-supported hybrid materials doped with highly near-infrared (NIR) luminescent neutral trikis-β-diketonate Yb3 + complex

Based on self-assembly of a trifluorinated and acylpyrazole-modified β-diketonate ligand HL ((Z)-3-methyl-1-phenyl-4-(2,2,2-trifluoro-1-hydroxyethylidene)-1H-pyrazol-5(4H)-one), LnCl₃⋅ 6H₂O (Ln = La, Yb or Gd) and 2,2′-bpy (2,2′-bipyridine), three trikis-β-diketonate complexes [Ln(L)₃(2,2′-bpy)] (Ln = La, 1; Ln = Yb, 2 or Ln = Gd, 3) were obtained, respectively. Further through physical doping, the series of PMMA-supported hybrid materials PMMA@[Ln(L)₃(2,2′-bpy)] with high thermal stability and good film-forming property are obtained. Especially for PMMA@2, the doping also causes the improved NIR luminescent property (Φ_em = 0.97%) in comparison to the individual Yb^3 +-β-diketonate complex 2 (Φ_em = 0.81%) even up to a concentration of 200:1.     

Synthesis,structure and magnetic properties of a copper molybdate hybrid inorganic/organic solid with a novel 10-connected three-dimensional network topology

Hydrothermal reaction of CuCl₂, MoO₃, and 4,4′-dipyridylketone (4,4′-dpk) afforded green crystals of the mixed metal oxide phase {[Cu₂(MoO₄)₂(4,4′-dpk)(H₂O)]·H₂O}_n (1). According to single-crystal X-ray diffraction, {Cu₂O₂} dimers link into 1-D {Cu₂O₂(μ-H₂O)}_n chains via bridging aqua ligands. These chains form [Cu₂(MoO₄)₂(H₂O)]_n slabs via linkage through tetrahedral molybdate anions. In turn, the copper molybdate slabs are pillared through tethering 4,4′-dpk ligands into a 10-connected three-dimensional lattice with an unprecedented 3¹²4³⁰5²6 topology. Variable temperature magnetic data above 140 K were fit to the Curie–Weiss law, with C = 0.17 cm³ K/mol Cu and Θ = 70 K, indicating likely ferromagnetic coupling within the dinuclear kernels of 1; low temperature data points towards the possibility of interdimer antiferromagnetic interactions.     

Crystal structure and chirality of adenosine-5′-diphosphate coordination complex

The first neutral coordination complex of adenosine-5′-diphosphate (ADP) with transition metal Cu(II) ion, [Cu(phen)(H₂ADP)(NO₃)]·H₂O (ADP–Cu) (ADP = adenosine-5′-diphosphate, phen = 1, 10-phenanthroline monohydrate) has been synthesized and investigated by X-ray single-crystal diffraction method. Based on its crystal structure and supramolecular assembly analysis, the molecular and supramolecular chirality of ADP–Cu was studied comprehensively by liquid- and solid-state circular dichroism (CD) spectroscopy. It is the first example of the study about the chirality and supramolecular chirality for polyphosphate nucleotide coordination complex.     

A novel three-dimensional cadmium(II) coordination polymer constructed from dinuclear molecular building block,syntheses, structure and photoluminescence property

A novel cadmium(II) coordination polymer, [Cd₂(pzdc)₂(4,4′-bpy)₂]·4H₂O (1) (H₂pzdc = pyrazine-2,3-dicarboxylic acid; 4,4′-bpy = 4,4′-bipyridine), has been synthesized by hydrothermal reaction of Cd(OAC)₂, H₂pzdc and 4,4′-bpy. Single-crystal X-ray diffraction analysis reveals that 1 constructed from dinuclear building blocks has a three-dimensional (3-D) structure with rob topology. Fluorescent measurement of 1 exhibits strong blue-green emission in the solid state at room temperature, and its framework possess remarkable thermal stability.     

A new 3-fold interpenetration of diamond-like network constructed from polyoxometalate building blocks

A new complex based on Keggin polyoxometalate building blocks, [Cu₂(bpy)₂(Hbpy)(H₂O)](PW₁₂O₄₀) (1) (bpy = 4,4′-bipyridine), has been hydrothermally synthesized and characterized by elemental analyses, IR, TG and X-ray single crystal diffraction. The X-ray structure analysis reveals that complex 1 exhibits an unprecedented 3-fold interpenetration of diamond-like network in the polyoxometalate chemistry.     

Two d10 coordination polymers based on 4,4′-(hexafluoroisopropylidene)diphthalic acid: Syntheses,structures and physical properties

Two novel coordination polymers, [Zn₂(FA)(4,4′-bipy)₂]·2H₂O (1) and Cd₂(FA)(2,2′-bipy) (2), (H₄FA = 4,4′-(hexafluoroisopropylidene)diphthalic acid, 4,4′-bipy = 4,4′-bipyridine, 2,2′-bipy = 2,2′-bipyridine), have been synthesized under hydrothermal conditions, and their structures were determined by single-crystal X-ray diffraction. Polymer 1 features an unusual three-dimensional (3D) network with (4 · 6² · 8³)(4² · 6² · 8²) topology. Polymer 2 has a complicated 3D framework and crystallizes in non-centrosymmetric space group (Fdd2) belonging to polar point group (C_2v), which displays a strong SHG response and ferroelectric properties. Moreover, the luminescent properties of 1 and 2 have also been investigated.     

Selective sensing of 2,4,6-trinitrophenol and detection of the ultralow temperature based on a dual-functional MOF as a luminescent sensor

A novel 3D Cd(II) MOF, {[Cd(Ccbp⁻)(4.4′-bpy)·H₂O]·(ClO₄⁻)·2H₂O} (1), (Ccbp⁻ = 3-carboxy-1-(4-carboxybenzyl)pyridin-1-ium, 4.4′-bpy = 4.4′-bipyridine), has been successfully synthesized and characterized. Complex 1 possesses a 3D 4-fold interpenetrating dia network with a pyridine cation basic skeleton. This Cd-MOF 1 can be applied as the first potential dual-functional luminescent sensing material for high selective and recyclable sensing of 2,4,6-trinitrophenol and quantitatively detecting the ultralow temperature from 10 to 60 K.     

A luminescent europium metal–organic framework with free phenanthroline sites for highly selective and sensitive sensing of Cu2 + in aqueous solution

A luminescent europium metal–organic framework [Eu(HL)(L)(H₂O)₂]·2H₂O (1) (H₂L = (2,3-f)-pyrazino(1,10)phenanthroline-2,3-dicarboxylic acid) with uncoordinated phenanthroline nitrogen sites was hydrothermally synthesized. It exhibits highly sensitive and selective sensing of Cu^2 + in aqueous solution. To the best of our knowledge, complex 1 is the first luminescent Eu-MOF with uncoordinated phenanthroline nitrogen sites for selective sensing of Cu^2 + in aqueous solution. The probable sensing mechanism was discussed in detail.     

A 3D Cu(II) coordination polymer constructed from BIBP (BIBP = 5,5′-bis(1H-imidazol-1-yl)-2,2′-bithiophene) ligand with semiconductive property

Hydrothermal reaction of Cu(NO₃)₂·3H₂O with BIBP and H₂hfipbb at 105 °C yielded a novel 3D Cu(II) coordination polymer, {[Cu₂(BIBP)_0.5(hfipbb)₂(CH₃CN)]·5H₂O}_n (1) [BIBP = 5,5′-bis(1H-imidazol-1-yl)-2,2′-bithiophene, H₂hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid)]. Compound 1 displays a 3D 2-fold interpenetrating framework with {4⁴.6⁶} sqp topology, containing interesting ⋯LRLR⋯ double helical chains. The compound 1 was characterized by IR spectra, elemental analysis, thermal analysis and single crystal X-ray diffraction. In addition, solid-state UV–vis spectra experiment shows that compound 1 exhibits semiconductive property with a band gap of 2.46 eV.     

Synthesis,crystal structure and magnetic properties of a new cyanide-bridged mixed-valence copper(I)/copper(II) clathrate

A unique cyanide-bridge mixed-valence Cu^I/Cu^II clathrate of formula [Cu^I₂(CN)₃][{Cu^II(tren)}₂(μ-CN)](CF₃SO₃)₂ [tren = tris(2-aminoethyl)amine] containing cyanide-bridged [{Cu^II(tren)}₂(μ-CN)]^3 + binuclear cations stacked between anionic honeycomb layered copper(I) cyanide networks, was synthesized and structurally characterized by single crystal X-ray diffraction. Variable-temperature magnetic susceptibility studies showed that the cyanide bridge mediates a strong antiferromagnetic interaction between the copper(II) centers (J = − 160 cm^− 1, the spin Hamiltonian being defined as H = −J S_A⋅S_B).