Cobalt(Ⅱ) and Cadimium(Ⅱ) Metal-organic Frameworks Supported by a Multicarboxylate Ligand

Two metal-organic frameworks(MOFs) of formulae [Co7(L)3(4,4′-BPy)2(OH)2(H2O)6]·-4 H2O(1) and [Cd2(L)(2,2′-BPy)2]n(2, H4L = 5-(3,5-dicarboxybenzyloxy)-isophthalic acid,2,2′-BPy = 2,2?-bipyridine, 4,4′-BPy = 4,4′-bipyridine) were synthesized under solvothermal conditions. The structures of 1 and 2 were characterized by X-ray single-crystal diffraction analysis.In complex 1, six cobalt atoms were connected by oxygen atoms to form a defect dicubane structure. The defect dicubane structures were further linked by Co(4,4?-BPy) units to generate a3-D network structure. Compound 2 displays a 2-D chain structure. The photoluminescent property of complex 2 is investigated. The results show the exclusive luminescence emission bands being originated from intraligand π-π^* transitions.

Aromatic Multicarboxylate Ligands Tuned One-and Three-dimensional Zn(Ⅱ) Coordination Polymers Based on 3-(1H-pyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole

Two aromatic multicarboxylate ligands tuned Zn(Ⅱ) coordination polymers, namely, {[Zn0.5(H2L)(tp)0.5(H2O)]H2O}n(1) and {[Zn2(HL)(btc)(H2O)]H2O}n(2)(H2L = 3-(1 Hpyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole, H2tp = terephthalic acid;H3 btc = 1,3,5-benzenetricarboxylic) have been synthesized. Their structures were characterized by single-crystal X-ray diffraction analysis, elemental analyses and infrared spectra. Compound 1 possesses a one-dimensional chain structure and is finally extended into a three-dimensional supramolecular architecture though hydrogen bonding interactions. Compound 2 shows a three-dimensional framework. Meanwhile, compounds 1 and 2 exhibit luminescent emission in the solid, and can be investigated as potential luminescent materials.

A New 2D Layered Barium Coordination Polymer [Ba(3-NPA)]_n: Synthesis, Crystal Structure, Thermal Stability and Luminescent Properties

A new two-dimensional （2D） barium（AA） coordination polymer [Ba（3-NPA）]n （1） has been obtained by the hydro/solvothermal reaction of the corresponding metal salt with 3-nitrophthalic acid （3-NPAH2）. Compound 1 was characterized by infrared spectrum, elemental analysis, powder X-ray diffraction （PXRD） and single-crystal X-ray diffraction analysis. Compound 1 crystallizes in triclinic, space group Pī with a = 4.9611（3）, b = 7.2599（4）, c = 12.9463（8） A, α = 89.0892（2）, β = 80.546（2）, γ = 73.211（2）°, V = 440.1（5） A3, Z = 2, C8H3BaNO6, Mr = 346.45, Dc = 2.614 g·cm^-3, μ = 4.526 mm^-1, S = 1.035, F（000） = 324, R = 0.0168 and wR = 0.0471 for 1712 observed reflections with I 〉 2σ（I）. （Aρ）max = 0.458, （Aρ）min = -0.565 e·A-3 and （A/σ）max = 0.001. In compound 1, each 3-NPA^2- ligand links six Ba（II） ions and each Ba（II） ion attaches to six 3-NPA^2- ligands to form an inorganic layer structure in the ab-plane. The phenyl groups of 3-NPA^2- ligands are grafted on the two sides of the inorganic layer, resulting in a two-dimensional （2D） layered structure. Furthermore, the thermal stability and luminescent properties of compound 1 have also been investigated in detail.

Synthesis of Multiester-appended and Multicarboxylic-appended Imidazolium Ionic Liquids

Multiester-appended imidazolium ionic liquids were synthesized in a quatemization reaction between the imidazole derivatives carrying single or double esters and ethyl chloroacetate or bromoethane. Multicarboxylic-appended imidazolium ionic liquids were achieved from the hydrolysis of the corresponding ionic liquids. The influences of multifunctional groups on the transition temperatures and viscosity of these new ionic liquids were investigated.

Solvothermal Synthesis and Characterization of Two Cd(Ⅱ) Coordination Polymers with Isomeric Multi-carboxylate Ligands

In this work two isomeric semi-rigid multi-carboxylate ligands 3,5-bi(3-carboxyphenoxy)benzoic acid(3-H_3BCP), 3,5-bi(4-carboxyphenoxy)benzoic acid(4-H_(3)BCP) and two rigid ligands(bis-triazole 4-(4-(4H-1,2,4-triazol-4-yl)phenyl)-4 H-1,2,4-triazole(L^(1)), 2-(1H-pyrazol-3-yl)pyrazine(L^(2))) have been employed to react with Cd(Ⅱ) salts under similar solvothermal reactions. Two novel Cd(Ⅱ) mixed-ligand coordination polymers, namely, {[Cd_3(3-BCP)_(2)(L^(1))]·3H_(2)O}n(1) and [Cd(4-HBCP)(L^(2))]_n(2), have been isolated. 1 displays a rare 2D cluster-based network while 2 displays a 3D supramolecular network through weak interactions. Solid-state luminescent properties and thermal analyses of 1 and 2 also have been determined, indicating strong fluorescent emissions and good thermal stabilities. Different coordination modes of two semi-rigid multi-carboxylate ligands and L^(1) and L^(2) also have been briefly discussed, which also reveal the great potential in the construction of these novel mixed-ligand luminescent frameworks with diverse structural motifs and unique functional properties.

Synthesis,characterization and fluorescence properties of a novel rare earth complex for anti-counterfeiting material

A novel ligand with two ester groups,two benzene rings and two carbox yl groups was synthesized. The composition and structure of the ligand were char acterized by the Fourier transform infrared spectroscopy(FT-IR) ,nuclear magnet ic resonance spectrum(NMR) and UV spectrometer. The rare-earth complex with the ligand and 1,10-phenanthroline(phen) was synthesized and structurally charact erized by FT-IR,TG and fluorescent spectrometer. The results showed that the no vel multicarboxyl ligand could efficiently transfer the energy to Eu3+ ions in t he complex and sensitize the luminescence of the rare earth ions,and the comple x could emit strong fluorescence of the rare earth ions.