The cooperative assembly of a hexagonal column shaped [Ti6O6][iPrO]66+ cluster and rhomboid Cu2I2 dimers using isonicotinic acid results in an unprecedented three-dimensional (3D) highly crystalline cluster-based Ti-MOF that features both giant sodalite cages with an inner diameter of 2.8 × 3.2 nm2 and 3D open square channels.

Two lanthanide MOFs, namely {{Me2NH2}[TbIII(L)]·3H2O·DMF}n (1) and {{Me2NH2}[EuIII(L)]·3H2O·DMF}n (2), based on the flexible ligand 5-(bis(4-carboxybenzyl)amino)isophthalic acid (H4L) have been synthesized under solvothermal conditions, where DMF = N,N-dimethylformamide. The two compounds exhibit a 3D structure with rectangle channels encapsulating [Me2NH2]+ cations. The microporous structure as well as the confinement of cations inside the MOFs pores allows 1 and 2 to act as dual-functional luminescent materials to detect nitroaromatics and metal ions. The experiments show that the luminescence of sample 1 in DMF solution was quenched when the nitrobenzene (NB) content reached 2.3 × 10−2 mol/L and concentration of Fe3+ reached 5 × 10−4 mol/L.Two novel lanthanide MOFs, {{Me2NH2}[LnIII(L)]·3H2O·DMF}n (Ln = Tb, Eu), have been successfully synthesized as a bifunctional luminescent probe for detecting nitrobenzene (NB) and Fe3+ ions.Download high-res image (145KB)Download full-size image

•Six Zn(II)/Cd(II) coordination polymers were prepared.•The coordination polymers display different topological network.•5-(3-Pyridylmethoxy)isophthalate exhibit five types of coordination modes.•The complexes are quite thermally stable and emit blue luminescence.Six coordination polymers based on 5-(3-pyridylmethoxy)isophthalic acid (H2L), namely [Zn2L2]n (1), [Zn2L2(1,3-bix)]n (2), [CdL(1,3-bix)]n·2nH2O (3), [CdL(azpy)0.5(H2O)]n (4), [CdL(btx)0.5]n (5), and [CdL(btmb)]n·2nH2O (6) (1,3-bix = 1,3-bis(imidazol-1-ylmethyl)benzene, azpy = 4,4′-azobispyridine, btx = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene, btmb = 4,4′-bis(1,2,4-triazol-1-ylmethyl)biphenyl), have been synthesized and characterized by elemental analyses, IR spectra, PXRD, thermogravimetry and X-ray structural analysis. Complex 1 is a 3D coordination polymer, simplified as a 4-nodal (4,4,5,5)-connected topology net with point symbol {43.63}{43.62.8}{44.65.8}{44.64.82}. Complex 2 is a 3D coordination polymer, simplified as a crs-d topology net with point symbol {6;82}{62;83;10}. Complex 3 is a 2D coordination polymer with a 2-nodal (3,5)-connected topology net. Complex 4 exhibits a 2D double-layered network with a 2-nodal (3,4)-connected topology net, assembled by two parallel [CdL]n layers pillared by azpy spacer. Complex 5 is a 3D coordination polymer, simplified as a 2-nodal (3,8)-connected topology net with point symbol {43}2{46.618.84}. Complex 6 shows a 2D double-layered network with a 2-nodal (3,5)-connected topology net, constructed from wave-like [CdL]n network pillared by btmb spacer. 5-(3-Pyridylmethoxy)isophthalate exhibits five types of coordination modes. Anhydrous or dehydrated substances of 1–6 were thermally stable to 300–400 °C. These Zn(II)/Cd(II) complexes emit blue luminescence originating from ligand-centered emission.Six 5-(3-pyridylmethoxy)isophthalate Zn(II)/Cd(II) coordination polymers were prepared and structurally characterized. 5-(3-Pyridylmethoxy)isophthalate exhibits five types of coordination modes in them. Complexes 1, 2 and 5 are 3D coordination polymer with different topology nets. Complexes 3, 4 and 6 are 2D coordination polymers with different structures. Their anhydrous frameworks are quite thermally stable. The complexes emit blue luminescence originating from ligand-centered emission.

•Four new Zn (II) coordination polymers have been synthesized and characterized.•The size of solvent molecular may as template to make more porosity for assembling structure.•The solvent effects play an important role for design these compounds.Four unique complexes with diverse coordination architectures were synthesized upon complexation of 5,5-(1,4-phenylenebis (methylene))bis (oxy)- diisophthalic acid (H4L) with zinc ions by using different solvent. namely, {[Zn(H2L) (bpp)]·DEF}n (1), {[Zn2(L) (bpp)2]·4H2O}n (2), {[Zn2(L) (pdp)2]·3H2O·DEF}n (3), {[Zn2(L) (pdp)2].4H2O}n (4). Complexes 1,2 and 3,4 are obtained by varying solvents to control their structures. The size of solvent molecular plays an important role to control different structure of these compounds. Compound 1 is 2D waved framework with (4, 4) grid layer as sql topology. Compound 3 displays a (4,6)-connected 2-nodal net with a fsc topology. Compounds 2 and 4 are all three-dimensional network simplified as (4,4)-connected 2-nodal net with a bbf topology. The photochemical properties of compounds 1–4 were tested in the solid state at room temperature, owing to their strong luminescent emissions, complexes 1–4 are good candidates for photoactive materials.

A homochiral three-dimensional framework material, [Cu7(4-bpt)6(CN)(H2O)] (1) (4-bpt = 3,5-bis(4-pyridyl)-1,2,4-triazole), has been successfully synthesized by solvothermal reaction, which is generated through an unusual spontaneous asymmetrical crystallization from achiral precursors, and its photocatalytic properties in degradation of organic dyes are also investigated.

•Two-interpenetrated microporous compounds.•Different stability.•Storage and separation of gases.Solvothermal synthesis afford two new porous metal-organic frameworks (MOFs): {[Cu6(L)3(H2O)4(py)2]·6(DMF)13(H2O)}n (1) and {[Cu6(L)3(H2O)6]·29(H2O}n (2). [5,5′-(1,3-phenylenebis(methylene))bis(oxy)diisophthalic acid (HL)]. Although possessing similar structures, the two MOFs have markedly different stabilities. Compound 1 and 2 can take up 16.8 mg/g and 15.9 mg/g of H2 at 77 K at 1 bar and 133 cm3/g and 120 cm3/g of H2 at 87 K (Fig. 8), which is higher than the performance of well-known MOFs PCN-6 and HKUST-1 at 77 K and 1 bar. Notably, both MOFs exhibited highly efficient, selective adsorption of CO2 over CH4 under ambient conditions. Such compounds may therefore prove useful for gas separation and purification.

Six zinc metal–organic frameworks, namely, [Zn(bpmb)(HCOO)]n·[Zn(bpmb)(OH)]n·4nH2O (1), [Zn(bpmb)(HCOO)]n (2), [Zn2(bpmb)2(fum)]n·9nH2O (3), [Zn3(bpmb)2(d-cam)2]n (4), [Zn2(bpmb)(1,3,5-btc)]n·nDMA (5), and [Zn(bpmb)(1,2,4,5-H2btec)]n·4nH2O (6) (Hbpmb = 3,5-bis(4-pyridylmethoxy)benzoic acid; H2fum = fumaric acid; d-H2cam = d-camphoric acid; 1,3,5-H3btc = 1,3,5-benzenetricarboxylic acid; 1,2,4,5-H4btec = 1,2,4,5-benzenetetracarboxylic acid; DMA = N,N-dimethylacetamide), were synthesized under solvothermal conditions. Their structures were characterized by EA, IR, PXRD, TG, and single-crystal XRD. Complex 1 is constructed of two independent neutral 3D MOFs with large 1D nanosized square channels, which are further entangled by each other to give an unexpected 4-fold [2 + 2] interpenetrating architecture. Complex 2 is a 3D MOF constructed from tetradentate bpmb and bidentate formate ligands, which is an isomer of the [Zn(bpmb)(HCOO)]n piece in 1. Complex 3 displays a 2D double-layered network that possesses 1D nanosized pores. Each 2D double layer is further interlocked with two neighboring ones to form an interesting 3D polycatenation array. Complex 4 possesses a 2D network constructed from a trinuclear [Zn3(COO)6N4] cluster and Zn–cam double-helical chain. Complex 5 is a 3D porous MOF constructed from tridentate bpmb and hexadentate 1,3,5-btc ligands. Complex 6 exhibits a 2-fold interpenetrating 2D wavelike (4,4) network constructed from bidentate bpmb and 1,2,4,5-H2btec ligands. The bpmb ligand adopts four types of coordination modes in 1–6. The secondary carboxylate ligands have obvious effects on their coordination architectures. Tetrahedral-, octahedral-, and trigonal-bipyramidal geometries around Zn(II) ions are observed. A general solvothermal method is proposed for preparing carboxylate complexes in DMF−H2O solution without any basic additive. In the preparation of 3, maleic acid is converted to a fumarate ligand. The thermal stabilities of six complexes and N2 adsorption behaviors of 1 and 3 are investigated. All the Zn(II) complexes emit blue luminescence originating from ligand-centered emission.

Eight coordination polymers based on H4L1/H4L2 (5,5′-(1,4/1,3-phenylenebis(methoxy))diisophthalic acid) and 3/4-abpt (4-amino-3,5-bis(3/4-pyridyl)-1,2,4-triazole) ligands were synthesized: [Co4(L1)2(4-abpt)(H2O)10.5]n (1), {[Zn2(L1)(4-abpt)(H2O)3]·5H2O}n (2), {[Co(H2L1)(3-abpt)(H2O)2]·0.5H4L1}n (3), {[Co2(L1)(4-abpt)2]·4H2O}n (4), {[Zn2(L2)(4-abpt)(H2O)]·2.5H2O}n (5), {[Zn2(L2)(4-abpt)(H2O)]·3H2O}n (6), {[Co1.5(HL2)(3-abpt)(H2O)]·H2O}n (7), and {[Zn1.5(HL2)(3-abpt)(H2O)]·H2O}n (8). Their structures were characterized by EA, IR, powder X-ray diffraction, thermogravimetric analysis (TGA), and single crystal X-ray diffraction. Complex 1 exhibits a three-dimensional (3D) metal–organic framework (MOF) composed of an interesting tetranuclear Co4(μ2-H2O)3(μ2-COO)4 cluster and 76-membered ring. Complex 2 shows a two-dimensional (2D) sheetlike network assembled by a one-dimensional (1D) [Zn2(L1)(H2O)3]n ribbon and 4-abpt linker. Complex 3 is a 1D nanotube coordination polymer constructed from parallel Co2(H2L1)2 rings pillared by two rows of 3-abpt spacers, which contains H4L1 guest molecule. Complex 4 displays a beautiful 3D porous MOF built by 2D sheetlike [Co2(L1)]n networks pillared by 4-abpt spacers. Complex 5 features a porous 3D MOF with regular nanosized rectangle tunnel. Complex 6 exhibits a 3D structure constructed from a double-layered [Zn2(L2)(H2O)]n network and 4-abpt linker. Complexes 7 and 8 are isostructural 3D polymers completed by 2D [Co1.5/Zn1.5(HL2)(H2O)]n networks pillared by 3-abpt spacers. H4L1 and H4L2 are fully or partly deprotonated in these complexes and exhibit six types of coordination modes. The 3/4-abpt ligands act as bidentate linkers. TGA shows that both tetracarboxylates ligands are thermally stable to 300 °C. Zn(II) complexes 2 and 8 are strong luminescent emitters. Variable-temperature magnetic studies indicate that complexes 1, 4, and 7 exhibit antiferromagnetic coupling between carboxyl-bridging CoII ions.

•Six 3-(4-hydroxypyridinium-1-yl)phthalate coordination polymers were prepared.•Complex 4 exhibits a 1D nano-tubular structure with larger cavity occupied by (H2O)5 cluster.•Four typical coordination modes of 3-(4-hydroxypyridinium-1-yl)phthalate are observed.•Complexes 1 and 3 exhibit blue luminescence.Hydro(solvo)thermal reactions of metal salts and 3-(4-hydroxypyridinium-1-yl)phthalic acid (H2L) with 4,4′-bipyridine (4,4′-bipy), N,N′-bis(4-pyridylmethyl)piperazine (4-bpmp), and 1,3-bis(4-pyridyl)propane (bpp) auxiliary dipyridyl ligands afforded six new coordination polymers, namely [CdL(H2O)]n (1), [CoL(4,4’-bipy)0.5(H2O)]n (2), [ZnL(4-bpmp)0.5(H2O)]n·2nH2O (3), [ZnL(bpp)]n·5nH2O (4), [Zn2L2(bpp)(H2O)2]n·nH2O (5) and [Zn2L2(bpp)(H2O)]n·4nH2O (6). They were characterized by elemental analysis, IR, PXRD, thermogravimetry and X-ray structural analysis. Complex 1 is a 1D ribbon coordination polymer. Complex 2 is a 2D coordination polymer constructed from L and 4,4′-bipy ligands, which is further extended into a 3D supramolecular framework through strong hydrogen bonds. Complex 3 features a 1D chain polymeric structure formed by [Zn2L2] dimer and 4-bpmp linker. Complex 4 exhibits a 1D nano-tubular structure with larger cavities, which are fully occupied by (H2O)5 clusters. Complex 5 displays a 1D linear chain structure. Complex 6 is a 2D layered coordination polymer. These complexes exhibit structural diversity originating from four typical coordination modes of 3-(4-hydroxypyridinium-1-yl)phthalate and various dipyridyl spacers. Thermogravimetric analyses demonstrate that the dehydrate complexes are thermally stable to ca. 260–300 °C. Complexes 1 and 3 emit strong blue luminescence originating from ligand-centered emission.Graphical abstractSix coordination polymers were prepared with 3-(4-hydroxypyridinium-1-yl)phthalate primary ligand which displays four typical coordination modes. [ZnL(bpp)]n·5nH2O (4) exhibits a 1D nano-tubular structure with larger cavity occupied by (H2O)5 cluster. The dehydrate coordination polymers are thermally stable to ca. 260–300 °C. Complexes 1 and 3 emit strong blue luminescence originating from ligand-centered emission.

A homochiral three-dimensional framework material, [Cu7(4-bpt)6(CN)(H2O)] (1) (4-bpt = 3,5-bis(4-pyridyl)-1,2,4-triazole), has been successfully synthesized by solvothermal reaction, which is generated through an unusual spontaneous asymmetrical crystallization from achiral precursors, and its photocatalytic properties in degradation of organic dyes are also investigated.