Synthesis, Structure and Properties of Lanthanide-Organic Frameworks with Imidazolylmethylisophthalate Ligands

2013 ◽  
Vol 68 (11) ◽  
pp. 1233-1238
Author(s):  
Xiao-Chun Cheng ◽  
Xiao-Hong Zhu

Three new lanthanide-organic frameworks {[Ln(L)(OClO3)(H2O)]·0.5H2O}n [Ln=Sm (1), Eu (2), Er (3)] have been prepared by hydrothermal reactions of the corresponding lanthanide oxide (Ln2O3), silver perchlorate (AgClO4) and 5-(imidazol-1-ylmethyl)isophthalic acid. The complexes have been characterized by single-crystal and powder X-ray diffraction, IR spectroscopy, and elemental analyses. In 1-3, the metal centers are eight-coordinated to show polyhedral coordination geometries with an LnO8 donor set. The imidazolyl groups are free of coordination, and the perchlorate and carboxylate groups bridge the Ln3+ cations leading to the formation of wave-like layer structures containing metal-chains. The fluorescence properties of complex 2 were investigated.

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4871
Author(s):  
Renata Łyszczek ◽  
Iwona Rusinek ◽  
Agnieszka Ostasz ◽  
Justyna Sienkiewicz-Gromiuk ◽  
Dmytro Vlasyuk ◽  
...  

Solvothermal reactions of lanthanide (III) salts with 1,2-phenylenediacetic acid in N,N′-dimethylformamide (DMF) solvent lead to the formation of the metal complexes of the general formula Ln2(1,2-pda)3(DMF)2, where Ln(III) = Pr(1), Sm(2), Eu(3), Tb(4), Dy(5), and Er(6), 1,2-pda = [C6H4(CH2COO)2]2−. The compounds were characterized by elemental analysis, powder and single-crystal X-ray diffraction methods, thermal analysis methods (TG-DSC and TG-FTIR), infrared and luminescence spectroscopy. They exhibit structural similarity in the two groups (Pr, Sm, and Eu; Tb, Dy, and Er), which was reflected in their thermal behaviours and spectroscopic properties. Single-crystal X-ray diffraction studies reveal that Sm(2) and Eu(3) complexes form 2D coordination polymers with four crystallographically independent metal centers. Every second lanthanide ion is additionally coordinated by two DMF molecules. The 1,2-phenylenediacetate linker shows different denticity being: penta- and hexadentate while carboxylate groups exhibit bidentate-bridging, bidentate-chelating, and three-dentate bridging-chelating modes. The infrared spectra reflect divergence between these two groups of complexes. The complexes of lighter lanthanides contain in the structure coordinated DMF molecules, while in the structures of heavier complexes, DMF molecules appear in the inner and outer coordination sphere. Both carboxylate groups are deprotonated and engaged in the coordination of metal centers but in different ways in such groups of complexes. In the groups, the thermal decomposition of the isostructural complexes occurs similarly. Pyrolysis of complexes takes place with the formation of such gaseous products as DMF, carbon oxides, ortho-xylene, ethers, water, carboxylic acids, and esters. The complexes of Eu and Tb exhibit characteristic luminescence in the VIS region, while the erbium complex emits NIR wavelength.


Author(s):  
Süheyla Özbey ◽  
Nilgün Karalı ◽  
Aysel Gürsoy

AbstractIn this study 4-(3-coumarinyl)-3-benzyl-4-thi azolin-2-one 4-methylbenzylidenehydrazone 3 was synthesised. An independent proof of the thiazolylhydrazone structure of 3 was achieved by single crystal X-ray diffraction analysis. Elemental analyses and spectral data (IR,


2013 ◽  
Vol 803 ◽  
pp. 80-84
Author(s):  
Yu Qi Liu ◽  
Yong Yang ◽  
Rui Yang ◽  
Xiao Jun Xu

A novel metalorganic coordination polymer, namely [Co3(bpd)5.5(NCS)6(NH3)]n2H2O (1) (bpd=1,4-bis (4-pyridyl)-2,3-diaza-1,3-butadiene), has been synthesized and characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray diffraction. Compound 1 presents 2D[3,4,-connected 3-nodal net with the point symbol (4268210)(4462)(8210). In addition, four identical 2D single nets is interlocked with each other in parallel, thus directly leading to the formation of a polycatenated layer (2D2D).


2013 ◽  
Vol 68 (9) ◽  
pp. 1007-1014 ◽  
Author(s):  
Xiao-Chun Cheng ◽  
Xiao-Hong Zhu ◽  
Hai-Wei Kuai

The hydrothermal reaction of Zn(II) nitrate with 5-(pyridin-2-ylmethylamino)isophthalic acid (H2L) yields the complex [Zn(L)(H2O)] 2H2O (1). When 2,2'-bipyridine (bpy) as auxiliary ligand and Cd(II) nitrate were used in the alkaline reaction system, [Cd(L)(H2O)(bpy)] 3H2O (2) was obtained. Complexes 1 and 2 have been characterized by single-crystal and powder X-ray diffraction, IR, elemental and thermogravimetric analyses. Complex 1 shows a 2D fes network structure with uninodal 3-connected (4.82) topology, which is further linked by hydrogen bonding to give rise to a 3D supramolecular framework; complex 2 displays a chain structure. Interestingly, tetranuclear water clusters were generated in 1, which are interlinked to fabricate a water chain structure. The fluorescence properties of 1 and 2 were investigated


2014 ◽  
Vol 69 (11-12) ◽  
pp. 1365-1374 ◽  
Author(s):  
Christoph Scheiper ◽  
Christoph Wölper ◽  
Dieter Bläser ◽  
Joachim Roll ◽  
Stephan Schulz

Abstract Three dinuclear zinc carboxylate complexes [L1-3Zn(μ,η2-O2CPh)]2 (1, 2, 4) containing either the bidentate N,N′-chelating β-diketiminate ligand RNC(Me)C(H)C(Me)NR (R = 2,6-iPr2-C6H3, L1, complex 1), the tridentate O,N,N-chelating ligand OC(Me)C(H)C(Me)NCH2CH2NMe2 (L2, complex 2) or the bis-N,N′-chelating bis-β-diketiminate ligand RNC(Me)C(H)C(Me)NNC(Me)- C(H)C(Me)NR (R = 2,6-iPr2-C6H3, L3, complex 4) were synthesized and characterized including single-crystal X-ray diffraction. Reaction of the neutral bis-β-diketimine (L3(H)2) with two equivalents of ZnMe2 leads to the expected heteroleptic dinuclear zinc complex L3(ZnMe)2 3 in 93% yield. Further reaction with benzoic acid PhCO2H leads to complex 4. Complex 2 forms a rather strong carboxylate-bridged dimer, whereas the carboxylate groups in complexes 1 and 4 act as asymmetrical bridges between both Zn atoms, pointing to the formation of a weakly bonded dimer. The zinc atoms in 1 and 4 are tetrahedrally coordinated, whereas in 2 the coordination number is increased to five due to the coordination of the pendant donor arm. The ring opening polymerization (ROP) of rac-lactide was investigated with the zinc complexes 1-4 and diazabicycloundec-7-ene (DBU) as a co-catalyst. Complexes 2 and 3 are active polymerization catalysts, which in the presence of DBU converted 200 equiv. of rac-lactide into polylactide within 10 min at ambient temperature. The analysis of the crude polymer showed that the lactide polymerization with catalyst 2 occurs via a slightly modified activated-monomer mechanism.


2018 ◽  
Vol 74 (11) ◽  
pp. 1434-1439
Author(s):  
Hong-Tao Zhang ◽  
Xiao-Long Wang

In recent years, much initial interest and enthusiasm has focused on the self-assembly of coordination polymers due to the aesthetics of their crystalline architectures and their potential applications as new functional materials. As part of an exploration of chiral coordination polymers, a new twofold interpenetrated two-dimensional (2D) coordination polymer, namely, poly[[tetraaquabis[μ3-(2R,2′R)-2,2′-(benzene-1,4-dicarboxamido)dipropionato-κ5 O,O′:O′′,O′′′:O′′]dicadmium(II)] trihydrate], {[Cd2(C14H14N2O6)2(H2O)4]·3H2O} n , has been synthesized by the reaction of Cd(CH3COO)2·2H2O with the designed ligand (2R,2′R)-2,2′-(benzene-1,4-dicarboxamido)dipropionic acid (H2 L). The compound has been structurally characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analysis. In the crystal structure, each CdII cation binds to three carboxylate groups from two crystallographically independent L 2− dianions. Four carboxylate groups link two crystallographically independent cadmium cations into a 4,4-connected secondary building unit (SBU). The resulting SBUs are extended into a two-dimensional folding sheet via the terephthalamide moiety of the ligand as a spacer, which can be simplified as a (4,4)-connected 4,4L15 net with the point symbol (3.53.62)(32.52.62). In the lattice, two independent folding sheets interpenetrate each other to yield a double-sheet layer. The resulting 2D layers pack in parallel arrays through intermolecular hydrogen bonds and interlayer π–π interactions. The thermal stability and photoluminescence properties of the title compound have been investigated and it exhibits an enhanced fluorescence emission and a longer lifetime compared with free H2 L.


2019 ◽  
Vol 75 (9) ◽  
pp. 1220-1227 ◽  
Author(s):  
Mei-rong Han ◽  
Shao-dong Li ◽  
Ling Ma ◽  
Bang Yao ◽  
Si-Si Feng ◽  
...  

A new mononuclear europium complex incorporating the (+)-di-p-toluoyl-D-tartaric acid (D-H2DTTA) ligand, namely, catena-poly[tris{μ2-3-carboxy-2,3-bis[(4-methylphenyl)carbonyloxy]propanoato}tris(methanol)europium(III)], [Eu(C20H17O8)3(CH3OH)3] n , (I), has been synthesized and characterized by IR spectroscopy, elemental analysis, powder X-ray diffraction and single-crystal X-ray diffraction analysis. The structure analysis indicates that complex (I) crystallizes in the trigonal space group R3 and exhibits an infinite one-dimensional chain structure, in which the Eu3+ ion is surrounded by six O atoms from six D-HDTTA− ligands and three O atoms from three coordinated methanol molecules, thus forming a tricapped trigonal prism geometry. The D-H2DTTA ligand is partially deprotonated and adopts a μ1,6-coordination mode via two carboxylate groups to link adjacent Eu3+ ions, affording an infinite one-dimensional propeller-shaped coordination polymer chain along the c axis, with an Eu...Eu distance of 7.622 (1) Å. Moreover, C—H...π interactions lead to the formation of helical chains running along the c axis and the whole structure displays a snowflake pattern in the ab plane. The circular dichroism spectrum confirms the chirality of complex (I). The solid-state photoluminescence properties were also investigated at room temperature and (I) exhibits characteristic red emission bands derived from the Eu3+ ion (CIE 0.63, 0.32), with a reasonably long lifetime of 0.394 ms, indicating effective energy transfer from the ligand to the metal centre. In addition, a magnetic investigation reveals single-ion magnetic behaviour. The spin-orbit coupling parameter (λ) between the ground and excited states is fitted to be 360 (2) cm−1 through Zeeman perturbation. Therefore, complex (I) may be regarded as a chiral optical-magneto bifunctional material.


2021 ◽  
Author(s):  
Adedibu Clement Tella ◽  
Samson Owalude ◽  
Vincent Adimula ◽  
Adetola Oladipo ◽  
Victoria Olayemi ◽  
...  

Abstract The coordination polymer [Cu2(TDPH)4(QNX)].DMF, (QNX = Quinoxaline; TDPH = 3,3-thiodipropionic acid), has been prepared by reaction of copper acetate, TDPH, and quinoxaline. The compound was characterized by elemental analysis, FTIR spectroscopy, and single-crystal X-ray diffraction. The crystal is monoclinic with a P21/n space group and dimensions of a = 12.889(3) Å, b = 14.983(4) Å, c = 14.091(3) Å, α = 90 °, β = 90.200(11) °, γ = 90 °, V = 2721.18 (2) Å3, Z = 4. The ligands are hexagonally coordinated to the Cu(II) centre in the form of Cu2O4N with one nitrogen atom from the quinoxaline ligand, and four oxygen atoms from four TDPH molecules in a monodentate fashion. The Cu-Cu bond length was 2.642(1) and 2.629(1) Å for the Cu1----Cu1 and Cu2----Cu2 bonds. The QNX ligand bridged the two copper atoms. The catalytic reduction of 4-nitrophenol to 4-aminophenol using NaBH4 in the presence of [Cu2(TDPH)4(QNX)].DMF, as catalyst was completed within 11 minutes. The 4-aminophenol product was confirmed using 1H NMR spectroscopy.


2018 ◽  
Vol 6 (2) ◽  
pp. 132
Author(s):  
Shuaibu Musa ◽  
S O. Idris ◽  
A D. Onu

The resulted complexes produced between Fe (III) and Co (II) with biological molecules like amino acids play an important role in human life. They can be used as bioactive compounds as well as in industries. Fe (III) and Co (II) complexes are synthesized with Alanine amino acid. The complexes were characterized by X-ray diffraction, magnetic suscetivility, elemental analysis (AAS), molar conductance, melting point, infrared and uv-visible spectrophotometry analyses. The elemental analyses were used to determine the chelation ratio, 1:3(metal: ligands) for iron (III) Alanine and 1:2 ratio for cobalt (II) Alanine. The molar conductivity of the complexes show that the complexes are not electrolytic in nature. The x-ray data suggest monoclinic crystal system for all the complexes with the exception of Co-alanine, which is hexagonal. The magnetic susceptivility and electronic spectra suggest the complexes are high spin with octahedral geometry.The complexes show enhance activity in comparable to the amino acid.  


2021 ◽  
Vol 68 (1) ◽  
pp. 102-108
Author(s):  
Yu-Mei Hao

A mononuclear copper(II) complex, [CuL] (1), and a phenolato-bridged trinuclear zinc(II) complex, [Zn3Cl2L2(DMF)2] (2), where L is the deprotonated form of N,N’-bis(4-bromosalicylidene)propane-1,3-diamine (H2L), have been prepared and characterized by elemental analyses, IR and UV-Vis spectroscopy, and single crystal X-ray diffraction. The Cu atom in complex 1 is in square planar coordination, while the terminal and central Zn atoms in complex 2 are in square pyramidal and octahedral coordination, respectively. The antibacterial activities of the complexes have been tested on the bacteria Staphylococcus aureus and Escherichia coli, and the yeast Candida parapsilosis.


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