Interesting 3D Framework Research Articles

Single-Ion Magnetism in a Three-Dimensional Thiocyanate-Bridged Dysprosium(III) Framework

New three-dimensional (3D) lanthanide framework compounds supported by bridging thiocyanate ligand and K+ cations, K4[Ln(NCS)4(H2O)4](NCS)3(H2O)2(1: Ln = Dy, 2: Ln = Tb, 3: Ln = Gd) have been synthesized. A single-crystal X-ray diffraction study showed that all three compounds were isostructural and crystallized in the I 2/a space group. The K+ ion form 2D layers with thiocyanates which are further linked by [Ln(NCS)4(H2O)4]- complexes and additional thiocyanate ions to generate an interesting 3D framework structure. Compound 1 shows slow magnetic relaxation behavior under a zero direct current (DC) field, indicating that 1 behaves as a single-ion magnet (SIM). As estimated from AC magnetic measurements, the effective energy barrier for spin reversal in 1 was Ueff = 42 cm–1. Slow relaxation of magnetization under a small external DC field was also detected for 2 and 3 at 1.8 K.

Synthesis and crystal structures of Zn(II) and Cd(II) coordination polymers derived from the flexible N-(4-carboxyphenyl)iminodiacetic acid and auxiliary ligands

Abstract Two coordination polymers [Cd3(CPIDA)2(bib)(H2O)2] n 1 and {[Zn6(CPIDA)4(bix)3]·8H2O} n 2 (H3CPIDA = N-(4-carboxyphenyl) iminodiacetic acid, bib = 1,4-bis(N-imidazolyl)butane, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), have been hydrothermally synthesized and characterized by analytical and IR spectroscopic data. Compound 1 displays an interesting 3D framework with trinodal (4,5)-connected topology, consisting of (4,4) rectangular grid double layers linked by trans-bib ligands. In 2, the corrugated nets with couples of central symmetrical chains constructed by CPIDA3− and bridging trans-bix ligands are pillared by infinite tubes made from CPIDA3− and cis-bix ligands to build a new 3D porous framework with parallelogram-shaped channels, exhibiting a pentanodal (3,4)-connected topology. Moreover, compounds 1 and 2 show intense solid state fluorescence at room temperature.

New three-dimensional Zn(II)/Cd(II)-based coordination polymers as luminescent sensor for Cu2+

Solvothermal reactions of the bifunctional 2,5-di(1H-1,2,4-triazol-1-yl)terephthalic acid (H2L), transitional metal Zn(II) and Cd(II) cations afford two coordination polymers, namely, [Zn(L)(H2O)]n (1), and [Cd2L2]n (2), (L = 2,5-di(1H-1,2,4-triazol-1-yl)terephthalic acid). Their structures and properties have been determined by single-crystal and powder X-ray diffraction analyses, IR spectra, elemental analyses, thermogravimetric analyses (TGA). Complex 1 exhibits an interesting 3D framework. The host network of complex 2 displays an unusual 3D network. Topology analyses reveal that 1 can be simplified as a 10-connected uninodal net with a point symbol of (312.414.519), and 2 adopts a 16-connected uninodal net with a point symbol of (339.476.55). In addition, luminescent investigations suggested that 1 and 2 exhibit highly selective and sensitive for Cu2+ over other cations with high quenching efficiency Ksv value 4.01 × 103 L·mol−1, 8.49 × 103 L·mol−1, respectively. The experimental result provides a helpful perspective for the design of sensitive fluorescent recognition sensors for Cu2+.

Structural diversity and magnetic properties of two metal-organic polymers based on bifunctional ligand of 2,5-di(1H-1,2,4-triazol-1-yl)terephthalic acid

Solvothermal reactions of the 2,5-di(1H-1,2,4-triazol-1-yl)terephthalic acid (H2L), ancillary bridging linkers oxalate, and transitional metal Co(II) cations afford two coordination polymers, namely, [Co(L0.5)2(H2O)]n (1), and [Co2L(ox)H2O]n (2), (L = 2,5-di(1H-1,2,4-triazol-1-yl)terephthalic acid, ox2− = oxalate). Their structures and properties have been determined by single-crystal X-ray diffraction analyses, IR spectra, elemental analyses, thermogravimetric analyses (TGA). Complex 1 exhibits an interesting 3D framework with double helical 2D sheets structure. The host network of complex 2 displays an unusual 3D networks by 1D chains, which are further connected by L2− ligands into dense packing structures. Topology analyses reveal that 1 and 2 can be simplified as a trinodal (4,5,6)-connected topological net with a point symbol of (42 · 62 · 82)(44 · 63 · 83)2(46 · 67 · 82) for 1, and (42 · 84)(46 · 66 · 83)(48 · 62)2 for 2. Besides, magnetic studies indicate both complexes 1 and 2 showing antiferromagnetic properties.

Rational Design of a 3D MnII -Metal-Organic Framework Based on a Nonmetallated Porphyrin Linker for Selective Capture of CO2 and One-Pot Synthesis of Styrene Carbonates.

A 3D MnII -porphyrin metal-organic framework (MOF), [{Mn2 (TCPP)⋅2H2 O}⋅DMF]n (MOF1) (TCPP=5,10,15,20-tetrakis(4-benzoate)porphyrin), was constructed; it exhibits an interesting 3D framework structure with two types of 1D channels of dimensions of 3.94×8.37 Å2 and 4.66×4.93 Å2 running along the crystallographic a axis. Owing to the presence of a nonmetallated porphyrin cavity, MOF1 exhibits selective storage of CO2 with an isosteric heat of adsorption value of 32.1 kJ mol-1 , which is further supported by theoretical calculations with the calculated binding energy (BE) of 29.78 kJ mol-1 . Interestingly, the nonmetallated nature of the porphyrin ligand was exploited for implantation of coordinatively unsaturated FeIII ions to generate a FeIII @MOF1 framework, which acts as an efficient recyclable catalyst for the oxidation of styrenes to the corresponding epoxides in the presence of PhIO as an oxidant at room temperature. Moreover, the one-pot synthesis of styrene carbonates from styrenes and CO2 was also achieved using FeIII @MOF1 as a catalyst. The rational design of a porous MnII -porphyrin MOF for the selective capture of CO2 and the one-pot synthesis of styrene carbonates at mild conditions is reported.

Four unprecedented cobalt(II) and cadmium(II) metal-organic frameworks based on a rigid tricarboxylate ligand: Synthesis, crystal structures, magnetic and fluorescence properties

A Co(II) MOF {[Co3(L)2(H2O)4](DMF)2}n (1) and three Cd(II) MOFs [Cd3(L)2(H2O)7]n (2), [Cd3(L)2(H2O)11]n (3) and [Cd3(L)2(DMF)2(H2O)]n (4) are synthesized based on the promising multifunctional tricarboxylate ligand 6-(3, 5-dicarboxyl phenyl) nicotinic acid (H3L). 1 exhibits a 3D framework with 1D channels which contains opposite-handedness helical chains based on the trinuclear Co(II) clusters. 2–4 are obtained depend on different reaction conditions. 2 displays a 3D framework, which is composed of two kinds of 2D layers linked with each other. 3 shows a rare tongue-and-groove-type bilayer structure. And 4 is an interesting 3D framework containing infinite 1D inorganic CdOCd chains. In these MOFs, the H3L ligand shows the versatile coordination modes and strong coordination ability. Furthermore, the magnetic and solid-state luminescent properties of the MOFs have been investigated.

A new Cu(II) three-dimensional network with 4,4′-oxybis benzoic acid: structural diversity, EPR, and magnetism

The copper derivative {[Cu4(oba)4(H2O)4]∙H2O}n (1) has been hydro(solvo)thermally synthesized by combining flexible 4,4′-oxybis benzoic acid (oba) and divalent copper nitrate. As a result of the potential coordination modes of carboxylate oxygens from the oba ligand, the aforementioned complex leads to the formation of an interesting 3D framework, as evidenced by single-crystal X-ray diffractometry. Concerning the topology in 1, the dimers [Cu2C4O8] are nodes of a 5-fold 4-connected uninodal net of the type lvt, with point symbol {42.84} and vertex symbol [4.4.84.84.88.88]. The encapsulation of the copper coordination polymer displays a moderate luminescent property. On temperature-dependent magnetic study, it reveals that the magnetic behaviour of 1 can be associated to a strong antiferromagnetic coupling between the two Cu(II) ions.

A series of alkaline earth metal coordination polymers constructed from two newly designed imidazole-based dicarboxylate ligands containing pyridinylmethyl groups

Two new imidazole-based dicarboxylate ligands, which are 2-(pyridin-4-ylmethyl)-1H-imidazole-4,5-dicarboxylic acid (H3pPyMIDC) and 2-(pyridin-3-ylmethyl)-1H-imidazole-4,5-dicarboxylic acid (H3mPyMIDC), have been designed and successfully synthesized. Both these multidentate ligands are then used to react with different kinds of alkaline earth metal ions under solvothermal conditions, leading to the construction of a series of new coordination polymers (CPs), namely, [Ba(μ5-HpPyMIDC)(H2O)]n (1), [Sr(μ5-HpPyMIDC)(H2O)]n (2), [Ca2(μ4-HpPyMIDC)2(H2O)2]n (3), {[Ca2(μ3-HpPyMIDC)(μ4-HpPyMIDC)(H2O)2]·H2O}n (4), [Ba(μ5-HmPyMIDC)(H2O)]n (5), {[Mg10(μ3-mPyMIDC)3(μ4-mPyMIDC)3(H2O)21]·SO4·12H2O}n (6) and {[Sr(μ2-H2mPyMIDC)2(DMF)2]n·H2O}n (7). Compounds 1 and 2 are isostructural, exhibiting two-dimensional (2D) network structures with a hexagonal honeycomb (6,3) topology if the corresponding metal ions are seen as 3-connected nodes. Compound 3 displays another type of 2D network, which is built by the connection of μ4-HpPyMIDC ligands and Ca(II) centres. Compound 4 is a binodal (3,4)-connected 3D framework with the Schläfli symbol of (6·82)(65·8). The 2D structure of compound 5 is similar to those of compounds 1 and 2, although different kinds of ligands are employed. Compound 6 exhibits an interesting 3D framework with a pcu topology by considering each unusual heptanuclear magnesium cluster as a 6-connected node. In compound 7, connection of μ2-H2mPyMIDC ligands with Sr(II) ions results in the formation of an uncommon 3D chiral framework containing two different types of 1D helical chains. The present results reveal that both these new imidazole-based dicarboxylate ligands containing flexible pyridinylmethyl groups show versatile coordination abilities and are good candidates for fabricating new CPs. Moreover, the thermogravimetric and solid-state luminescence properties of all the compounds have also been studied.

Three metal induced 3D coordination polymers based on H3BTC and 1,3-BIP as co-ligands: Synthesis, structures and fluorescent properties

Three new 3D coordination polymers, {[Co(BTC)2(H2O)2][Co(1,3-BIP)(H2O)4]2}n (1), {[Zn3(BTC)2(1,3-BIP)3]·2DMF}n (2) and {[Cu3(BTC)2(1,3-BIP)3]·DMA}n (3), were synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction, powder XRD, FT-IR, TGA and elemental analysis techniques. Although the three MCPs were constructed from the same tricarboxylate and N-donor ligands, their structures are quite different. Complex 1 features a 1D+2D→3D framework constructed by 2D [Co(BTC)2(H2O)2]n4n− layers and 1D [Co(1,3-BIP)(H2O)4]n2n+ chains, in which there exist three kinds of O–H⋯O hydrogen bonds, not only among the coordinated water molecules but also among the coordinated water molecules and carboxylate O atoms. Although complexes 2 and 3 have similar chemical formula, their structures are different. Complex 2 exhibits a 3D→3D twofold interpenetrating framework, while complex 3 shows an interesting 3D framework. Furthermore, the fluorescent properties of the complexes 1 and 2 were also investigated in the solid state at room temperature.

Novel heteroleptic lanthanide organic frameworks containing pyridine-2,5-dicarboxylic acid and in situ generated piperazine-2,5-dicarboxylic acid from piperazine: Hydrothermal synthesis and luminescent properties

Two novel 3D lanthanide metal-organic frameworks [Ln(pydc)(pip)1/2(H2O] (Ln=Ce (1) and Pr (2), H2pydc=2,5-pyridinedicarboxylic acid, H2pip=2,5-piperazinedicarboxylic acid have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffractions (PXRD), and single-crystal X-ray diffractions. Field emission scanning electron microscopy (FESEM) was used for morphological analysis. Complexes are isostructural and feature interesting 3D frameworks. Both compounds crystallize in the monoclinic system, space group P21/c. Structural analyses of 1 and 2 show that Ln3+ ions connect with each other through H2pydc and H2pip. To the best of our knowledge, they are the first heteroleptic lanthanide polymers obtained through in situ 2,5-piperazinedicarboxylic acid syntheses. Moreover, thermal and luminescent properties of the compounds have been investigated.

Two novel 3D self-threading coordination polymers with CdSO4 topology: Syntheses, structures and properties

Two new isostructural metal-organic frameworks, namely [Co(HL)(bpp)]·0.5H2O (1) and [Zn(HL)(bpp)]·3H2O (2) (H3L=5-(2′-carboxy-biphenyl-4-ylmethoxy)-isophthalic acid, bpp=1,3-bis(4-pyridyl)propane), have been hydrothermally synthesized and further characterized by single crystal X-ray diffraction, powder X-ray diffraction, elemental analyses, IR spectra and TG analyses. Compounds 1 and 2 exhibit interesting 3D frameworks of (65.8)-CdSO4 topology with dangling arm (i.e. the uncoordinated 2′-carboxy-biphenyl-4-ylmethoxy group of HL ligand). The remarkable feature of these two compounds is that each dangling arm threads into two 6-membered rings belonging to the 3D net itself, displaying the self-threading character. The magnetic properties of 1 and photoluminescence of 2 have also been investigated.

Co(H2O)6]2+and H3O+encapsulated in a unique 3D anionic Co(ii) framework with hydrophilic hexagonal and circular channels

An interesting Co-based 3D framework exhibits a rare example where [Co(H2O)6]2+and H3O+ions not only act as counterions to balance the negatively charged structure, but also may serve as templates in the assembly of the anionic framework with open hydrophilic channels.

A New Three-Dimensional La(III) Coordination Polymer Based on A 1,4-Naphthalenedicarboxylate

A new 3D La(III) coordination polymer, namely, [La2(1,4-ndc)3(H2O)2]·H2O (1), has been synthesized under hydrothermal condition (1,4-ndc = 1,4-naphthalenedicarboxylate). The compound was structurally characterized by single-crystal X-ray diffraction analysis. In 1, the 1,4-ndc ligands bridge neighboring La(III) ions to generate an interesting 3D framework. The thermal behavior of the compound was also studied in detail.

Two Organic–Inorganic Hybrid 3D {P5W30}‐Based Heteropolyoxotungstates with Transition‐Metal/Ln–Carboxylate–Ln Connectors

Two unique organic-inorganic hybrid polyoxometalates constructed from Preyssler-type [Na(H2 O)P5 W30 O110 ](14-) ({P5 W30 }) subunits and TM/Ln-carboxylate-Ln connectors (TM=transition metal, Ln=lanthanide), KNa7 [{Sm6 Mn(μ-H2 O)2 (OCH2 COO)7 (H2 O)18 }{Na(H2 O)P5 W30 O110 }]⋅22 H2 O (1) and K4 [{Sm4 Cu2 (gly)2 (ox)(H2 O)24 }{NaP5 W30 O110 }]Cl2 ⋅25 H2 O (2; gly=glycine, ox=oxalate) have been hydrothermally synthesized and characterized by elemental analyses, IR spectra, UV/Vis-NIR spectra, thermogravimetric analyses, power X-ray diffraction, and single-crystal X-ray diffraction. Compound 1 displays one interesting 3D framework built by three types of subunits, {P5 W30 }, [Sm2 Mn(μ-H2 O)2 (OCH2 COO)2 (H2 O)5 ](4+) , and [Sm4 (OCH2 COO)5 (H2 O)13 ](2+) , whereas 2 also manifests the other intriguing 3D architecture created by three types of subunits, {P5 W30 }, [SmCu(gly)(H2 O)8 ](4+) , and [Sm2 (ox)(H2 O)8 ](4+) . To our knowledge, 1 and 2 are the first 3D frameworks that contain {P5 W30 } units and TM/Ln-carboxylate-Ln connectors. The fluorescent properties of 1 and 2 have been investigated.

Structures and magnetic properties of several novel lanthanide coordination polymers based on thiophene-2,5-dicarboxylic acid

Eight novel lanthanide complexes: {Ln(TDA)1.5(H2O)2} n (Ln = Pr( 1a ), Nd( 2a )) and {Ln(TDA)(Ac)(H2O)} n (Ln = Pr( 1 ), Nd( 2 ), Eu( 3 ), Gd( 4 ), Tb( 5 ), Dy( 6 ); TDA = Thiophene-2,5-dicarboxylic acid anion) have been constructed by hydrothermal reaction. Structural analyses reveal that complexes 1a and 2a belong to the space group C 2/ c , exhibiting three-dimensional (3D) frameworks. Complexes 1 - 6 with P 21/ c space group were prepared in the presence of excessive ammonium acetate, giving rise to interesting 3D frameworks different from those of 1a and 2a . Magnetic property studies of 4 - 6 reveal the weak antiferromagnetic interaction exists between adjacent Gd3+ in 4 . The complex 6 displays rather rare slow magnetization relaxation behavior in 3D frameworks.

Structural evolution and magnetic properties of CoII coordination polymers varied from 1D to 3D constructed by 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene

Seven Co(II) coordination polymers, [Co(btx)(3)(H(2)O)(2)](ClO(4))(2)·(btx)·2H(2)O (1), [Co(btx)(3)(H(2)O)(2)](BF(4))(2)·(btx)·2H(2)O (2), [Co(btx)(2)(H(2)O)(2)](NO(3))(2)·2H(2)O (3), [Co(btx)(2)Cl(2)] (4), [Co(btx)(BA)(2)(H(2)O)(2)]·2HBA (5), [Co(btx)(IPA)] (6) and [Co(3)(btx)(3)(BTA)(2)(H(2)O)(2)] (7) (btx = (1,4-bis(1,2,4-triazol-1-ylmethyl)benzene), HBA = benzoic acid, H(2)IPA = isophthalic acid, H(3)BTA = benzene-1,3,5-tricarboxylic acid), have been hydrothermally synthesized and characterized. 1 and 2 are isostructural and show a 1D Co-μ(2)-btx-Co chain structure, in which btx acts as both a bridging and terminal ligand. 3 is also a 1D chain structure but different from 1 and 2. The Co(II) ions are bridged by double μ(2)-btx to form Co(2)-btx(2) rings, which were further connected into 1D chains by sharing the Co(II) ions of the rings. 4 exists as a 2D grid with (4,4) topology structure. When aromatic acid was introduced to the synthetic system, three other coordination polymers 5-7 were obtained. In 5, the 1D chain is as that of 1, except that the terminal ligand was replaced by BA(-). 6 shows a two-fold parallel interpenetration framework featuring a 6-c uninodal net with (3(3),4(6),5(5),6) Schlafli topological symbol. 7 is an interesting 3D framework, which contains a 2-nodal net motif with the unprecedented (3(6),4(2),5(6),6)(3(9),4(9),5(3))(2) topology structure. The influence of the varieties of the structures and magnetic properties are studied and discussed in detail.

Role of molar-ratio, temperature and solvent on the Zn/Cd 1,2,4-triazolate system with novel topological architectures

Five members of the Zn/Cd triazolate family, [Zn(TAZ)(OAc)]n (1), [Zn4(TAZ)6(OAc)2]n (2), [Cd3Cl3(TAZ)3(DMF)2]n (3), [CdCl2(TAZ)]n·n(H2O) (4) and [Cd2Cl(μ4-AmTAZ)2(μ-AmTAZ)]n (5), have been synthesized from TAZ/AmTAZ and corresponding metal salts, where TAZ, AmTAZ and DMF are 1,2,4-triazole, 3-amino-1,2,4-triazole and N,N′-dimethylformamide, respectively. X-ray analysis shows that all compounds except 4 manifest interesting 3D frameworks with novel topologies. Compounds 1 and 2 are temperature-and-solvent controlled assemblies and possess 3D (3,4,6)-connected (3.72)2(32.4.73)(32.4.76.86) topology and 3D (3,6)-connected (4.82)3(83)(46.86.123) topology, respectively. However, compounds 3 and 4 are molar-ratio-dependent compounds. The framework of 3 is a 3D (3,4,5)-connected one with (4.102)(4.62)2(43.62.8)2(64.106) topology, in which the 1D channels are filled with coordinated DMF, while only a 1D chain-like motif is formed in 4. In addition, a 3D (4,6)-connected (3.42.52.6)2(32.42.54.65.72)(32.44.54.64.7) topology is observed in the framework of 5, where AmTAZ is used instead of TAZ in the syntheses of compounds 1–4. Solid state measurements reveal that all these coordination polymers are thermostable and luminescent under ambient conditions.

Binuclear, 2D grid and 3D interlocking coordination polymers based on 1,2,4,5-benzenetetracarboxylic acid and 4,4′-azobispyridine

Abstract Three new nickel(II) complexes [Ni2(btec)(azopy)2(H2O)8]·2H2O (1), {[Ni(H2btec)(azopy)(H2O)2]·(azopy)}n (2) and {[Ni4(btec)2(azopy)3(H2O)10]·8H2O}n (3) (H4btec = 1,2,4,5-benzenetetracarboxylic acid; azopy = 4,4′-azobispyridine) have been synthesized by tuning the reaction temperature and the metal–ligand ratio. They were characterized by single-crystal X-ray diffraction and elemental analysis. 1 shows a binuclear structure, 2 exhibits a 2D grid, and 3 features an interesting 3D framework with (63)(4.62)(42.62.82) topology formed by two types of interlocked 2D layers.

Crystal structure of a new coordination polymer [LaAg(Pydc)(HPydc)(C2O4)0.5(H2O)2] n (H2Pydc = pyridine-3,5-dicarboxylic acid)

A new 3D coordination polymer, [LaAg(Pydc)(HPydc)(C2O4)0.5(H2O)2] n (I) (H2Pydc = pyridine-3,5-dicarboxylic acid), has been hydrothermally synthesized and characterized by elemental analyses and single crystal X-ray diffraction. The X-ray diffraction analysis reveals that I (C15H11AgLaN2O12) crystallizes in triclinic space group P $$ \bar 1 $$ and features an interesting 3D framework constructed by 2D layers via strong Ag-Ag interactions. Unit cell parameters for I (n = 1): a = 7.749(2), b = 8.316(1), c = 14.239(3) A, α = 97.64(2)°, β = 100.12(2)°, γ = 94.37(2)°, and Z = 2.

Diamondoid Three-Dimensional Metal-Organic Framework Showing Structural Transformation with Guest Molecules

The potential of carboxylate and imidazole-based mixed ligands for forming metal organic frameworks (MOFs) is demonstrated with 4-(1H-imidazole-1-yl)benzoic acid (HIBA) to generate a flexible material. Reaction of HIBA with Cd(NO3)2·6H2O under solvothermal condition in N,N-dimethylformamide (DMF), produces a three-dimensional MOF, {[Cd(IBA)2].2DMF}n (1⊃2DMF), which on heating at 60 and 200 °C turns opaque, forming {[Cd(IBA)2]·DMF}n (1⊃DMF) and {[Cd(IBA)2]}n (1), respectively, as characterized by PXRD, TGA, and elemental analysis. Either of these compounds on keeping in dry DMF for 15 days affords the original compound, i.e., showing reversibility deduced from PXRD. When a crystal of 1⊃2DMF is immersed in moist N,N-diethylformamide (DEF) in a vial open to atmosphere, a new compound, {[Cd(IBA)2]·DEF·H2O}n, (2) is formed in 1 month in a single-crystal to single-crystal (SC-SC) fashion. Also, a crystal of 1⊃2DMF on immersing in moist DMF produces another interesting 3D framework {[Cd(IBA)2.H2O]·DMF·3H2O}n, (3) in a SC-SC transformation. These coordination polymers show interesting 4-fold interpenetrating diamondoid 3D network structures.