A unique three-dimensional coordination polymer constructed from 4,4′-biphenyldicarboxylate and zinc(II)

Zinc(II) coordination polymer [Zn(bpdc)]_n (bpdc=4,4^′-biphenyldicarboxylate) (1) with a unique entanglement PtS structure was synthesized by hydrothermal reaction of zinc nitrate and 4,4-biphenyldicarboxylic acid in aqueous sodium hydroxide solution.     

A novel two-dimensional coordination polymer constructed from bi-capped Keggin molybdenum–vanadium polyoxoanions and nickel ethylenediamine complexes

A novel two-dimensional (2-D) solid material [Ni(en)₂]₂{SiMo^VI₈V^IV₆O₄₂[Ni(en)₂]₂}·4H₂O 1 (en = ethylenediamine) has been hydrothermally synthesized and structurally characterized by IR, UV–Vis spectrum, elemental analysis, XRD, ESR, XPS, X-ray diffraction analysis, magnetic property analysis and electrochemistry study. Single-crystal X-ray analysis reveals that the 2-D framework of compound 1 is based on Mo/V/Si bicapped Keggin clusters interconnected by nickel ethylenediamine complexes. Magnetic susceptibility measurement indicates that compound 1 exhibits antiferromagnetic coupling interactions.     

A triple chain coordination polymer constructed from ZnTPP and a bis(4,4′-dipyridylamine) ligand

A novel coordination polymer [(ZnTPP)₃ L¹]_n·(DMF)_2n 1 (ZnTPP = zinc(II) tetraphenylporphyrinate) has been hydrothermally synthesized from a tetrapyridyl ligand N,N,N′,N′-tetra(4-pyridyl)-1,4-phenylenediamine (L¹) and characterized by elemental analysis, IR, and single-crystal X-ray diffraction analyses. In the crystal, L¹ utilizes all four pyridyl N atoms to coordinate at the axial positions of two different ZnTPP units. The first utilizes two axial positions for coordination, and the second coordinates at only one of the axial positions. Thus, the former ZnTPP units and two pyridyl nitrogens of L¹ ligands are linked alternately to afford a zigzag chain, and two of the latter porphyrin units are appended to both sides of each repeating unit of the zigzag chain by coordination to the remaining two nitrogens of each L¹ ligand. Interestingly, the appended porphyrins form two straight lines at both sides of the zigzag chain by the linkage of π???π interactions between the phenyl rings. Finally, a triple chain is formed. The solid state emission of 1 is also studied.     

A 3D cadmium(II) coordination polymer constructed from new β-diketone-functionalized pyridinecarboxylate and 4,4′-bipyridine ligands

A new cadmium(II) coordination polymer [Cd₂(L)₂(bpy)]_n·nCH₃OH (1) (H₂L = 2-(3-oxo-3-phenylpropionyl)-6-pyridinecarboxylic acid N-oxide, bpy = 4,4′-bipyridine), has been synthesized from the reaction of H₂L, 4,4′-bipyridine with CdSO₄·8/3H₂O. Compound 1 is an exceptional non-interpenetrating three-dimensional framework and contains double helical chains and rare cross bpy configuration. Interestingly, these helical chains can span two different directions on other alternate layers. Compound 1 shows intense photoluminescence at room temperature.     

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,structure and luminescent property of a new europium-based coordination polymer constructed from biphenyl-3,4′,5-tricarboxylic acid

A new 3D lanthanide metal–organic framework Eu(BPT)(DMF)(H₂O)•(H₂O)_0.5] (1) has been synthesized by self-assembly of Eu(III) ions and ligand biphenyl-3, 4′, 5-tricarboxylate under solvothermal reaction conditions. X-ray crystallography reveals that 1 exhibits a (3, 6)-connected topology, with dinuclear europium clusters as 6-connected nodes and C₂-symmetric ligands BPT as 3-connected nodes. In addition, the luminescence sensitization of 1 via excitation of the ligand is highly efficient.     

A 3D K–Cu heterometal–organic coordination polymer with luminescent properties constructed from two kinds of Cu-cyanide complex units and binuclear K oxo-cluster

A novel 3D heterometal–organic coordination polymer [{K₂(H₂O)₆} {Cu₃(Hpimdc)₂(CN)₂}{Cu₂(H₃pimdc)₂(CN)}]·2H₂O (1) (H₃pimdc = 2-propyl-1H-imidazole-4,5-dicarboxylic acid) has been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, PXRD, UV–vis, and single-crystal X-ray diffraction. In complex 1, adjacent K⁺ ions are linked through H₃pimdc to form binuclear chain units {K₂(H₂O)₆}_n, which connect with unique Cu-cyanide complex linker {Cu₃(CN)₂(Hpimdc)₂} to form 2D layers. The 2D layers are further connected via another linkage unit {Cu₂(CN)(H₃pimdc)₂} to form 3D frameworks with (4¹16²)₂(3³4²5¹10¹12³16⁴) topology. The H₃pimdc ligand in 1 exhibits μ₂- and μ₄-two kinds of coordination fashions. In addition, the N₂ adsorption, fluorescence, and photocatalytic properties of polymer 1 are evaluated detailed.     

A novel one-dimensional single helix derived from 2,2′-bipyridine based Zn(II) species directed self-assembly with 1,2-benzenedicarboxylate

The self-assembly assisted by 2,2^′-bipyridine (2,2^′-bpy) protected zinc(II) species with 1,2-benzenedicarboxylate (1,2-BDC) has yielded a novel one-dimensional single helical coordination polymer of [Zn(2,2′-bpy)(1,2-BDC)(H₂O)]_n in a racemate of right- and left-handed helices, which was crystallographically studied and thermally analyzed.     

Two-dimensional cobalt-bipyridinedicarboxylate coordination polymer: [Co(2,2′-bipyridine-5,5′-dicarboxylato) (H2O)]·(H2O)

Hydrothermal reaction between cobalt(II) nitrate and 2,2^′-bipyridine-5,5^′-dicarboxylic acid in the presence of NaOAc gave a two-dimensional coordination-polymer of cobalt(II), [Co(2,2^′-bipyridine-5,5^′-dicarboxylato)(H₂O)]·(H₂O) (1). X-ray structure determination showed that compound 1 has a two-dimensional infinite network based on cobalt-bipyridinedicarboxylate building blocks and has a relatively small channel of 5.0×6.6 Å.     

A novel Zn6Co3 cluster-based heterometallic coordination polymer with PMG3 − linker formed via in situ decarboxylation from H4PMIDA

A novel Zn₆Co₃ cluster-based heterometallic coordination polymer, [Zn₆Co₃(PMG)₆(H₂O)₄]·12H₂O (1), has been hydrothermally synthesized, in which the PMG^3 − (N-(phosphonomethyl)glycinate) as a multifunctional ligand was firstly formed via in situ decarboxylation from original ligand N-(phosphonomethyl)imino-diacetic acid during the hydrothermal reaction. The complex was characterized by elemental analysis, FT-IR, powder X-ray diffraction, thermal analysis and single-crystal X-ray diffraction techniques. Its structure features a 2D framework constructed by [Zn₆Co₃(PMG)₆(H₂O)₄] pinwheel-like heteronuclear clusters, which contains rings with two tropisms. Through extensive O–H⋯O hydrogen bondings, the adjacent 2D layered structure further extends into a 3D supramolecular network. Moreover, the solid-state fluorescence property of this complex has also been investigated at room temperature, which exhibits a good fluorescent emission.     

A molecular layer “fabric” with orthogonally woven coordination polymer chains

Crystals of [Cu(ox)(dpa)(H₂O)]_n (1, ox = oxalate, dpa = 4,4′-dipyridylamine) were prepared by hydrothermal reaction of potassium copper oxalate and dpa. Single-crystal X-ray diffraction showed the formation of orthogonally oriented sets of 1D [Cu(ox)(dpa)(H₂O)]_n chains that interlock in a 1D + 1D ➔ 2D manner to form woven “warp-and-woof” supramolecular layers. Thermogravimetric analysis indicated that the structure of 1 remained stable to about 175 °C.     

One novel 3D tetranuclear cadmium coordination polymer based on 2,3′,4,5′-biphenyltetracarboxylic acid: Synthesis,crystal structure and luminescence

One novel 3D cadmium coordination polymer, namely, {[Cd₂(bptc^4 −)(ox^2 −)_0.5(H₂O)₂] · 4.5H₂O}_n (1), has been hydrothermally synthesized through a reaction of 2,3′,4,5′-biphenyltetracarboxylic acid (H₄bptc) with divalent cadmium salt in the presence of a second ligand (ox = oxalic acid). X-ray single crystal structure analysis reveals that tetranuclear cadmium clusters are formed by linking two Cd1 and two Cd2 ions with carboxyl groups. Each ox^2 − ligand, with a bidentate chelating mode, connects two Cd2 ions from two adjacent tetranuclear clusters to afford 1D zigzag cadmium cluster chains. Furthermore, 1D chains are connected by bptc^4 − ligands to extend a 3D framework with one-dimensional channels along the [001] direction. From a topology view, complex 1 exhibits an unprecedented 2-nodal 4, 10-connected net with the Schläfli symbol of {4⁶}₂{4⁹. 5¹².6²².7²}. The luminescence analyses reveal that complex 1 shows an emission maximum at 437 nm, which may be attributed to the intra-ligand transition. A red shift of 31 nm compared with H₄bptc ligand was observed and the luminescent decay lifetime is 2.74 ns, which indicates that it might be a potential blue light-emitting candidate. In addition, it was also characterized by elemental, IR spectra, PXRD and TG analyses.     

A puckered 2D copper coordination polymer with dimensions 14.91×12.63 Å

The polymeric complex [Cu(spcp)₂(H₂O)]_n·(H₂O)_2n (spcp⁻=4-sulfanylmethyl-3-phenylcarboxylate pyridine) with puckered grids of dimensions 14.91×12.63 Å was obtained in the reaction of the Cu(OAc)₂·5H₂O with Na(spcp) by solvothermal method.     

A novel catalyst system for the synthesis of N,N′-Methylenebisacrylamide from acrylamide

N,N′-Methylenebisacrylamide (MBAA), which is an important raw material in a widely industrial area, was synthesized using convenient catalysts. The synthesized monomer was fully characterized by the elemental analysis, fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), ¹H-NMR, ¹³C-NMR, GC/MS, and high performance liquid chromatography (HPLC) analysis. Six different homogeneous and heterogeneous catalysts were used to obtain maximum monomer yield. The MBAA was obtained with 95% yield by using Cu(II) catalyst containing carboxylate groups ligands.     

2,2′-Bipyridine-Modified Tamoxifen: A Versatile Vector for Molybdacarboranes

Investigations on the antitumor activity of metallacarboranes are sparse in the literature and limited to a handful of ruthena- and molybdacarboranes. In this study, the molybdacarborane fragment [3-(CO)₂-closo-3,1,2-MoC₂B₉H₁₁] was combined with a vector molecule, inspired by the well-known drug tamoxifen or 4,4′-dihydroxytamoxifen (TAM-diOH). The molybdacarborane derivative [3,3-{4-[1,1-bis(4-hydroxyphenyl)but-1-en-2-yl]-2,2′-bipyridine-κ²N,N′}-3-(CO)₂-closo-3,1,2-MoC₂B₉H₁₁] ( 10 ), as well as the ligand itself 4-[1,1-bis(4-hydroxyphenyl)but-1-en-2-yl]-2,2′-bipyridine ( 6 ) showed cytotoxic activities in the low micromolar range against breast adenocarcinoma (MDA-MB-231, MDA-MB-361 and MCF-7), human glioblastoma (LN-229) and human glioma (U-251) cell lines. In addition, compounds 6 and 10 were found to induce senescence and cytodestructive autophagy, lower ROS/RNS levels, but only the molybdacarborane 10 induced a strong increase of nitric oxide (NO) concentration in the MCF-7 cells.     

A novel 3D silver(I) coordination polymer exhibiting unprecedented μ3- and μ4-bonding modes of 2-aminopyrazines

The unprecedented μ₃- and μ₄-bonding modes of NH₂pyz (NH₂pyz = 2-aminopyrazine) are observed for the first time in a novel 3D Ag(I) coordination polymer [Ag₇(NHpyz)₆(ClO₄)]_n (1) which was obtained by reaction of Ag₂O, NH₂pyz and NaClO₄ in H₂O/CH₃OH/NH₃ media under ultrasonic treatment. Compound 1 is a 3D framework with infinite 1D Ag belts incorporating diverse Ag···Ag interactions. Moreover, 1 exhibits photoluminescence maximized at 494 nm upon 300 nm excitation at room temperature, which may be mainly assigned to ligand-to-metal charge transfer (LMCT) mixed with metal-centered (d-s/d-p) transitions. Semiconducting behavior of 1 was also measured at room temperature with σ value of 6.78 × 10^?6 S cm^?1.     

Spin canting in a novel (3,4)-connected mixed-valence cobalt coordination polymer based on oxalates and [Co(Hbiim)3] (H2biim = 2,2′-biimidazole) building blocks

Hydrothermal treatment of cobalt chloride, 2,2′-biimidazole (H₂biim), oxalate acid and NaOH at 160 °C for five days produced a three-dimensional mixed-valence metal-organic framework [Co^III(Hbiim)₃]₂[Co^II₃(ox)₃]·4H₂O (1). Compound 1 exhibits a 3D network with tri-nodal (3-c)₂(4-c)₃ topology, in which [Co^III(Hbiim)₃] building blocks as 3-connected nodes, and Co^II ions as 4-connected nodes. The magnetic measurements reveal that compound 1 exhibits a spin canting antiferromagnetic coupling between adjacent Co^II ions.