Syntheses,structures and luminescence of two cadmium entangled coordination polymers based on bis(imidazole) and biscarboxylate ligands

Two entangled coordination polymers [Cd₂(bib)(bdc)₂]_n (1) and [Cd₂(bib)(bda)₂]_n (2) were synthesized by the hydrothermal reaction (bib = 1,4-bis(2-methyl-imidazol-1-yl)butane, bdc = 1,2-benzenedicarboxylate, bda = 1,4-benzenediacetate). 1 exhibits an unusual 6-connected self-catenated 3D network based on Cd₂(COO)₂ dimer with the point symbol of (4⁴·6¹⁰·8). 2 exhibits a 3-fold interpenetrating 3D pcu network based on Cd₂(COO)₂ dimer. The different conformations of bib ligands (the anti–anti–anti conformation in 1 and gauche–anti–gauche conformation in 2) play the key role in the construction of different structures in 1 and 2. The luminescence and thermal stability were investigated.     

Two new 3-D coordination polymers with 5-tert-butyl isophthalic acid and flexible N-donor co-ligands bearing linear trinuclear secondary building blocks

Two new 3-D coordination polymers bearing linear trinuclear secondary building blocks with mixed bridging ligands, {[Ni₃(tbip)₂(Htbip)₂(bib)₂]·4H₂O}_n (1) and {[Co₃(tbip)₂(Htbip)₂(btb)₂]·4H₂O}_n (2) (H₂tbip = 5-tert-butyl isophthalic acid, bib = 1,4-bis(imidazol-1-yl)butane, btb = 1,4-bis(1,2,4-triazol-1-yl)butane), were obtained and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, single-crystal X-ray crystallography and powder X-ray diffraction. Both complexes 1 and 2 display similar 3D 6-connected pcu networks containing the linear trinuclear [M₃(COO)₆] (M = Ni and Co) clusters as nodes.     

Syntheses,topological analyses and magnetic properties of two 3D supramolecular nickel-organic frameworks constructed from 1,3,5-benzenetricarboxylate and flexible imidazole-based ligands

Two supramolecular nickel-organic frameworks, [Ni(HBTC)(bix)]_n (1) and [Ni₃(BTC)₂(mbix)₃(H₂O)₄]_n · 6nH₂O (2) (bix = 1,4-bis(imidazole-l-yl-methyl)benzene, mbix = 1,3-bis(imidazole-l-yl-methyl)benzene, and H₃BTC = 1,3,5-benzenetricarboxylate), have been hydrothermally prepared by the assembly of H₃BTC, Ni²⁺ with bix or mbix. Compound 1 shows a 2D layer structure, whose 3D supramolecular structure exhibits a fsc topology when hydrogen-bonging interactions between the adjacent layers are taken into account. Compound 2 manifests an unprecedented 2D (3, 4)-connected topological net. The 3D supramolecular framework of 2 is formed through π?π stacking interactions between the adjacent layers. The magnetic studies show that 1 features overall ferromagnetic property whilst 2 presents strong zero-field splitting (ZFS) when treated as a mononuclear model. Furthermore, the IR and TGA properties of 1 and 2 were also studied.     

Syntheses,structures and luminescence of three copper(I) cyanide coordination polymers incorporating flexible N-donor ligands

Three copper(I) cyanide coordination polymers, namely [Cu₈(CN)₈(btmb)₂]_n (1), [Cu(CN)(btmb)_0.5]_n (2) and [Cu₂(CN)₂(dpa)]_n (3) (btmb = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene, dpa = di(4-pyridyl)amine), were synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectra, PXRD and thermogravimetric analyses. Single-crystal X-ray diffraction analyses reveal that complex 1 is an interesting 2D double-layered network constructing from eight distinct Cu(I) centers, eight μ₂-cyanides and two tetradentate cis-btmb ligands. Complex 2 is a ladder-like coordination polymer assembled by CuCN linear chain and bidentate trans-btmb linker. Complex 3 has a 2D wave-like network constructing from CuCN zigzag chain and V-shape dpa spacer. These coordination polymers are thermally stable up to 270–300 °C. They emit blue luminescence originating from ligand-centered emission.     

Self-assembly of a novel 3D copper(I)-tetrazolate supramolecular framework via interpenetration of porous 2D double-layer motifs

The self-assembly of CuCN and 1H-TAZ ligand under hydrothermal conditions generated a novel three-dimensional hybrid supramolecular framework, namely, [Cu₆(TAZ)₄(CN)₂]_n (1) (TAZ = tetrazole). Single-crystal X-ray diffraction show that [Cu₂(TAZ)₂] binuclear subunits are linked by μ₂- and μ₃-CN groups to give a 2D double-wave-shaped network, which possesses 1D channels with four open-windows. The 2D bilayers interpenetrated each other to form the 3D supramolecular framework of 1.     

A highly electrical conducting, 3D supermolecular Ag(I) coordination polymer material with luminescent properties

A stable, 3D supermolecular material, [Ag(H₂O)(2,6-ndc)_0.5(L)_0.5]_n (2,6-H₂ndc = 2,6-naphthalenedicarboxylic acid; L = N,N′-di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxydiimide (dpndi)) with high electrical conducting ability was successfully synthesized under a solvothermal condition and characterized by single-crystal X-ray diffraction, IR spectroscopy and thermogravimetric analysis (TGA). The electrical conducting and photoluminescence properties were investigated.     

Ionothermal syntheses of two coordination polymers constructed from 5-sulfoisophthalic acid ligands with 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liquid as solvent

Two coordination polymers, namely, [Co(IM)₆][Co₂(SIP)₃] (1) (IM = imidazole, H₃SIP = 5-sulfoisophthalic acid) and [BMIM]₂[Cd₂(SIP)₃] (2) (BMIM = 1-n-butyl-3-methylimidazolium) were synthesized in ionothermal reactions by using ionic liquid 1-n-butyl-3-methylimidazolium tetrafluoroborate as solvent. Single-crystal X-ray analyses revealed that 1 has an anionic 1D polymeric chain charge balanced by an uncommon [Co(IM)₆]²⁺ cation. Complex 2 features an anionic 2D layer containing unique tetranuclear [Cd₄(CO₂)₆(SO₃)₂] cluster wherein the four Cd atoms are co-planar. The imidazolium cation [BMIM]⁺ of the ionic liquid acting as charge compensating agent intercalated into the [Cd₂(SIP)₂]^2n? interlayers in structure 2. The rich ionic environments of the ionic liquid may be particularly helpful in the formation of the anionic frameworks of 1 and 2.     

A new 2D 5-connected coordination polymer based on 3,4-bis(pyridin-4-ylmethoxy)benzoic acid ligand

A new 2D 5-connected coordination polymer [Zn₃(HL²)(1,4-bdc)₃] (1) (HL² = 3,4-bis(pyridin-4-ylmethoxy)benzoic acid, 1,4-H₂bdc = 1,4-benzenedicarboxylate) has been hydrothermally constructed using HL², 1,4-bdc ligands as linear linkers and Zn₃-clusters as 5-connected nodes. In addition, powder X-ray diffraction, photoluminescent property and thermogravimetric analysis for 1 are investigated in detail.     

A 3D photoluminescent cadmium(II)-organic framework with unusual pentanuclear cluster as secondary building unit

A crystalline 3D MOF with unique pentanuclear Cd(II)-cluster as SBU, [Cd₅(H₂O)₄(ap)₃(trz)₄]_n (1) (H₂ap = adipic acid, Htrz = 1,2,4-triazole), was isolated by hydrothermal method, which exhibits strong Htrz-based luminescent emission. More interestingly, ap ligands in 1 were observed to play the important roles for both the aggregate of polynuclear motif and the extension of the infinite 3D framework.     

A new Cu-based metal-organic framework built upon infinite 1D rod-shaped secondary building units

A new Cu(II) metal-organic framework {[Cu_1.5(1,3-bdc)(dtb)(OH)(H₂O)](H₂O)}_n (1) (1,3-H₂bdc = 1,3-benzenedicarboxylic acid, dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene), has been synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, and IR spectra. Compound 1 features a 3-D open framework constructed by infinite 1D rod-shaped [Cu₃(OH)₂]_n chains as secondary building units. The magnetic property of the complex has also been investigated.     

Diverse architectures of hybrid materials induced by different mixed-ligands and applications in luminescence

For investigating the effects of different azacyclo-assisting ligands and O-donor bridging ligands on the structural construction, three different structural complexes, namely, {Zn(DBTA)(phen)(H₂O)}_n (1) (DBTA = 2, 5-Dibromo-terephthalic acid, phen = 1,10-Phenanthroline), [Zn(DBTA)(bimb)]_n (2) (bimb (1,4-bis(imidazole-1-ylmethyl)benzene) and {[Zn₂(bmimb)(PO₄)₂]·(H₂O)₂}_n (3) (bmimb = 1,2-bis(methylimidazole-1-ylmethyl) benzene) have been constructed by different mixed-ligands and Zn atoms. Their structures have been characterized by single-crystal X-ray diffraction analysis, elemental analysis, and Infrared spectroscopy. Complex 1 exhibits a common 2D layer with 4,4-connected topology. Complex 2 features an interesting 2-fold interpenetrating net with the aid of long-chain flexible azacyclo-assisting ligands. Complex 3 shows 3D supramolecular architecture with tetranuclear water cluster filling in the pores. Their fluorescence properties were also measured.     

Pillar-layered Zn–triazolate–carboxylate frameworks tuned by the bend angles of ditopic ligands

In the utilization of three ditopic ligands with different bend angles as pillars, we reported herein three pillar-layered Zn–triazolate–carboxylate frameworks, namely, [Zn₂(ATRZ)₂(BDC)]_n (1), [Zn₂(ATRZ)₂(TPDC)]_n·2nDMF (2) and [Zn₂(ATRZ)₂(ADDC)]_n (3) (ATRZ = 3-amino-1,2,4-triazole, H₂BDC = 1,4-benzenedicarboxylic acid, H₂TPDC = 2,5-thiophenedicarboxylic acid, and H₂ADDC = 1,3-adamantanedicarboxylic acid). Single crystal structural analyses demonstrate that different geometries of ditopic carboxylate pillars not only result in Zn–ATRZ layers adopting various corrugated configurations, but also give rise to 3,4-connected self-interpenetrated net of 1 and non-interpenetrated nets of 2 and 3. All these compounds exhibit high thermal stability and blue photoluminescence.     

A unique 3D Co(II)-MOF based on [Co6(μ3-OH)4]8 +n chains: Synthesis,crystal structure,and magnetic property

A novel metal-organic framework, [Co₆(μ₃-OH)₄(ndc)₄(bip)₂(H₂O)₂]_n (1)[H₂ ndc = 1,4-naphthalenedicarboxylic acid, bip = 1,5-bis(imidazole-1-yl)pentane], constructed from unique [Co₆(μ₃-OH)₄]^8 +_n chains containing alternate [Co₄(OH)₂]^6 + and [Co₂(OH)₂]^2 + subunits, was reported, which has a new (3,3,8,12)-connected or 12-connented fcu/cubic network and shows weak antiferromagnetic interaction between the adjacent Co(II) ions mediated through the carboxylate and hydroxyl groups.     

Novel silver(I) compounds assembled from hybrid ligands based on linear or T-shaped coordination environment

Two novel 1D compounds {[Ag₃(Hbptc)(bpa)₂]·H₂O}_n (1) and [Ag₂(H₂bptc)(bpp)₂]_n (2) (H₄bptc = 3,3′,4,4′-benzophenonetetracarboxylic acid, bpa = 1,2-bis(4-pyridyl)ethane and bpp = 1,3-bis(4-pyridyl)propane) were synthesized and structurally characterized. The crystal structures of compounds exhibit two kinds of ladder-like chains based on linear or T-shaped coordination environment of Ag(I). Fluorescence spectra of compounds 1 and 2 indicate the unusual intensity of fluorescent emission upon photoexcitation which may be attributed to ligand-to-metal charge transfer and Ag–Ag interactions.     

Syntheses and structures of cadmium(II) and cobalt(II) coordination polymers based on 1,1′-(2,2′-oxybis(ethane-2,1-diyl))bis(1H-imidazole) and carboxylate ligands

Two novel coordination polymers containing Cd(II) and Co(II) metals, connected via 1,1′-(2,2′-oxybis(ethane-2,1-diyl))bis(1H-imidazole) (L) ligand, have been synthesized. Compound [Cd(L)₂(p-BDC)] · 2H₂O (1) (p-BDC = 1,4-benzenedicarboxylate anion) is a three-dimensional interdigitated supramolecular architecture. Compound [Co(L)(BTCA)_0.5] (2) (BTCA = 1,2,3,4-butanetetracarboxylate anion) possesses a unique (3,4)-connected 3D framework with (8³)₂(8⁵ · 10) topology.     

1D nickel(II) coordination polymer with pyrimidine and pivalate bridges: Synthesis,structure and magnetic properties

New 1D polymeric compound [Ni₂(μ-OH₂)(μ-Piv)₂(Piv)₂(μ-pym)(η¹-pym)₂]_n (3, Piv is an anion of pivalic acid) was synthesized upon the reaction of the nickel(II) pivalate complex Ni₉(OH)₆(Piv)₁₂(HPiv)₄ (3) and pyrimidine (pym) in MeCN. Complex 3 was characterized by the X-ray diffraction study and magnetic measurements. It is shown that neighboring Ni sites in the 1D metal chain in 3 are coupled by weak antiferromagnetic interactions with two exchange parameters of J₁ = –3.1 and J₂ = –1.2 cm^–1.     

pH-controlled the formation of 4-sulfocalix[4]arene-based 1D and 2D coordination polymers

Three manganese/4-sulfocalix[4]arene complexes, namely, {H[(C₂₈H₂₀O₁₆S₄)Mn(H₂O)₄Mn_0.5(H₂O)₂]}_n ·6nH₂O (1), {NH₄[(C₂₈H₂₀O₁₆S₄)Mn(H₂O)₄Mn_0.5(H₂O)₂]}_n · 5nH₂O (2), [(C₂₈H₂₀O₁₆S₄)Mn₂(H₂O)₈]_n · 6nH₂O (3), have been synthesized under different pH conditions. Complex 1, which exhibits a one-dimensional (1D) structure, is formed at [H⁺] = 2.0 mol L⁻¹. Reaction at pH 4 leads to another one-dimensional (1D) coordination polymer of 2. At pH 5, a two-dimensional (2D) coordination polymer of complex 3 is formed, showing clearly structural effects on pH response.     

Rapid synthesis of a novel cadmium imidazole-4,5-dicarboxylate metal–organic framework under microwave-assisted solvothermal condition

A novel three-dimensional (3D) coordination polymer, [Cd(μ₃-HIDC)(bbi)_0.5]_n (1) (H₃IDC = 4,5-imidazoledicarboxylic acid, bbi = 1,1’-(1,4-butanediyl)bis(imidazole)), has been synthesized under microwave heating solvothermal conditions and characterized by elemental analysis, IR, TG, and single crystal X-ray diffraction. The crystal structure reveal that compound 1 consists of 2D brickwall-like networks of [Cd(μ₃-HIDC)]_n, which are further linked through μ₂-bbi to generate a 3D structure. Compound 1 is stable up to 330 °C and displays strong blue fluorescent emission at room temperature. This work demonstrates that microwave-assisted solvothermal synthesis method is an efficient and fast way to prepare metal coordination polymers.     

Three Ag(I)–cyanide coordination polymers with metal bonds tuned by N-heterocyclic ligands

Hydrothermal reactions of AgNO₃, K₃[Fe(CN)₆] with N-heterocyclic ligands afforded three novel Ag(I)–cyanide coordination polymers, [Ag₂(CN)₂(tpt)]_n (1), {[Ag(CN)(bpe)_0.5][Ag(CN)]}_n (2) and [Ag(CN)(btmb)_0.5]_n (3) (tpt = 2,4,6-tris(4-pyridyl)-1,3,5-triazine, bpe = 1,2-bis(4-pyridyl)ethane, btmb = 1,2-bis(1,2,4-triazol-1-ylmethyl)benzene). In complex 1, two Ag(CN) linear chains are bridged by bidentate tpt ligand to form a ladder-like structure, which are further connected by AgAg metal bond to generate a 2D polymeric network. Complex 2 is an interesting 3D supramolecular architecture assembled by 2D [Ag¹(CN)(bpe)_0.5]_n network and linear [Ag²(CN)]_n chain combined by strong AgAg metal bond. Complex 3 is a 1D ladder-like double-chain polymer constructed from Ag–cyanide linear chains and btmb spacer, which is further extended to a 2D supramolecular network by Ag–Ag weak interaction. The Ag–Ag metal interactions play important roles in the construction of three coordination polymers. Complexes 1 and 2 are respectively thermally stable at 300 and 180 °C. Complexes 1 and 3 emit strong blue luminescence.     

Syntheses,crystal structures and luminescence properties of lanthanide coordination polymers involving in situ C–S bond cleavage of (4-pyridylthio)acetic acid

Lanthanide coordination polymers with the formula [Ln₂(C₂O₄)₃(H₂O)₆]_n (1) (Ln = Nd, 1) and [Ln₂(C₂O₄)₃(pythioH)₂(H₂O)₂]_n (Ln = Eu 2; Dy 3; Er 4) pythio = 4-pyridinethiolate) were synthesized by treating Ln^III nitrates with (4-pyridylthio)acetic acid under hydrothermal conditions. Single-crystal X-ray diffraction studies indicate that these lanthanide coordination polymers consist of extended oxalate-bridged two-dimensional layer structure. Interestingly, in situ C–S bond cleavage occurred and (4-pyridylthio)acetic acid was transformed into 4-pyridinethiolate and oxalate. The complexes 2 and 3 display strong fluorescent emission in the solid state at room temperature.