Four Ag(I)/Co(II) complexes based on a flexible V-shaped ligand 3,3′, 4,4′-diphenylsulfone tetracarboxylic acid (H4dstc), namely [Ag(bpe)2]·H3dstc (1), {[Ag2(H2dstc)(bpp)(H2O)]·H2O}n (2), {[Co2(dstc)(bpe)2(H2O)2]·2H2O}n (3) and {[Co4(dstc)2(bpa)3(H2O)6]·7H2O}n (4) have been synthesized in the presence of different rod-like N-donor ligands 1,2-di(4-pyridyl)ethylene (bpe), 1,3-bis(4-pyridyl)propane (bpp), and 1,2-bis(4-pyridyl)ethane (bpa). In complex 1, the H3dstc– ligand does not take part in coordination but balances the charge by its one deprotonated carboxylate group. Complex 2 contains two different motifs: a cationic 1D chain [Ag(bpp)]+ and an anionic 1D meso-helix [Ag(H2dstc)(H2O)]–. Interestingly, the non-covalent hydrogen bonding interactions extend such simple discrete units or 1D chains into 3D supramolecular architectures. Complex 3 represents a 3D binodal 4-connected (64·82) network, while complex 4 can be simplified as a primitive cubic (pcu) network. In addition, the photoluminescence of 1 and 2 and the magnetism of 3 and 4 are investigated, respectively.

A new flexible 3D porous metal-organic framework (MOF) with 1D open nanotube, [Co 2 (µ 5 -CTA I )(dpe)(H 2 O) 2 ] n ·6 n (H 2 O) ( 1 ) (CTA = cyclohexane-1,2,4,5-tetracarboxylic acid, dpe = 1,2-di(4-pyridyl) ethylene) has been prepared and structurally characterized. Meanwhile, each 1D nanotubes filled with 1D water chain with dimension of 13.711 × 12.275 Å 2 . Compound 1 represents a new example that collapse/deform upon dehydration/hydration and shows adsorb H 2 O selectively over organic solvents.

A series of new coordination polymers have been hydrothermally synthesized by the combination of adamantane dicarboxylates and long conformational bis-triazole ligand with Zn(II)/Co(II)/Cd(II) ions, formulated as {[Zn(ADC)(btmb)]center dot 3H(2)O}(n) (1), {[Co-2(ADC)(2)(btmb)(2)]center dot H2O}(n) (2), {[Cd(ADA)(btmb) (H2O)]center dot H2O}(n) (3), {[Zn(ADA)(btmb)(0.5)]center dot H2O}(n) (4), {[Co-2(ADA)(2)(btmb)(2)]center dot H2O}(n) (5), [Cd-2(ADA)(2)(btmb)(2)](n) (6) (H(2)ADC 1,3-adamantanedicarboxylic acid, H(2)ADA = 1,3-adamantanediacetic acid and btmb 4,4'-bis(1,2,4-triazol-1-ylmethyl)biphenyl). All crystalline polymers have been structurally characterized by single-crystal X-ray diffraction, elemental analysis, IR, TGA and XRD. Crystal structural analysis reveals that complex 1 has a 1D infinite tubular structure. Complexes 2 and 3 possess the similar 2D undulating layer structure with (4(4))-sql network. Interestingly, only the polymer 2 displays a 2-fold parallel interpenetrating 2D -> 2D framework. Complex 4 presents a binodal (3,4)-connected V2O5-type net. While both 5 and 6 feature binodal (3,5)connected networks. In particular, intermolecular forces have important effects on the formation and strengthening of the supramolecular architecture. Structural diversities indicate that distinct adamantane dicarboxylates, conformational bis-trizaole ligands and the nature of metal ions play crucial roles in modulating structures and topologies of the final polymers. Moreover, the thermal stability of crystalline sample 1 has been investigated through TGA and VT-XRD measurements. The luminescent properties of 1, 3, 4 and 6 have been studied.

A novel one-dimensional (1D) metal−organic nanotube {[Cd2(ADC)2(bpp)3(H2O)]2·8H2O}n (MONT-1), based on mixed organic ligands, has been synthesized and characterized. MONT-1 presents the first independent 1D metal−organic nanotube with mesohelical structure and a fascinating topology of 1D → 2D interdigital architecture with side arms. This compound also exhibits high thermal stability and blue-shift emission with large intensity enhancement compared with that of the free ligand and can be explored for potential blue luminescent materials.

The reaction between ErCl3·6H2O and H2bmdc (H2bmdc = benzimidazole-5,6-dicarboxylic acid) produced two distinct complexes: 1D helical complex {[Er(Hbmdc)(bmdc)(H2O)3]·3H2O}n (1) obtained under hydrothermal condition at 160°C and discrete complex [Er2(Hbmdc)2(bmdc)2(H2O)8]·8H2O (2) under ambient temperature, evaporated from the mother liquor of 1. The crystal structures of the complexes were determined by X-ray single-crystal diffraction. Through comparison of complexes 1 and 2, we found that enhanced temperature favors the formation of higher dimensional products and lower amount of coordinated water. Both complexes are characterized by IR, elemental analysis, X-ray powder diffraction and thermogravimetric analysis.

An investigation into 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and cupric or cadmium complexes with a large variety of aliphatic alpha,omega-dicarboxylic acids HOOC-X-COOH (X (CH2)(n), n = 0-4 corresponding to oxalic acid (H(2)ox), malonic acid (H(2)mal), succinic acid (H(2)suc), glutaric acid (H(2)glu) and adipic acid (H(2)adi); CH=CH, maleic acid (H(2)male) and fumaric acid (H(2)fum)) is performed. Ten novel metal-organic architectures, [Cu-2(bpt)(ox)(2)](n)center dot 2.92nH(2)O (1), [Cu(bpt)(mal)(H2O)](n)center dot 2nH(2)O (2), [Cu(bpt)(glu)](n) (3), [Cu(bpt)(adi)](n) (4), [Cu-2(bpt)(2)(fum)(2)](n)center dot 3nH(2)O (5), [Cd(bpt)(mal)(H2O)](n) (6), [Cd(bpt)(suc)](n) (7), [Cd(bpt)(glu)](n)center dot nH(2)O (8), [Cd-2(bpt)(2)(male)(2)](n)center dot 2nH(2)O (9), and [Cd(bpt)(fum)(H2O)](n)center dot nH(2)O (10) were successfully synthesized through varying the organic acid linkers. The molecule 1 is a 3D pillared-layer framework with the open channels encapsulating infinite 1D water chains. Complex 2 shows the contorted 2D layer, which is extended to a 2-fold interpenetrated 3D supramolecular net by antidromic R-4(2)(8) hydrogen-bonding pattern. Compound 3 is a grid-like layer motif with the terminal bpt ligands as pendants. The MOFs 4 and 5 present two-fold interpenetrating primitive cubic (alpha-Po) coordination networks. Interestingly, discrete tetrameric water clusters exist in the micropores of the MOF 5. For the cadmium complex 6, six-coordinated metal centers link malonate and bpt to form interdigitated layers through edge-to-face pi-pi stacking interactions. Coordination polymer 7 can be considered as six-connected self-penetrated topological 3D network, in which the right-and left-handed helices are alternately arranged into a wavy Cd/succinate layer. Flexible glutarate with cadmium atoms produces a 1D ribbon, and is further linked by bpt ligands to produce the 2D double-layered motif 8. Incorporating with rigid butenedioic acid, the reaction of seven-coordinated cadmium and bpt leads to two distinct 2D (4,4) layered frameworks 9 and 10, with a one-dimensional Cd-O chain observed in the former framework. A systematic structural comparison of these ten complexes indicates that the final polymeric structures could be tuned through the introduction of the different backbone length and flexibility of the aliphatic dicarboxylates. In addition, host-guest chemistry of MOFs 1 and 5, and the luminescent properties of cadmium compounds were discussed.

Six new coordination polymers, namely {[Zn(btec)(0.5)(btmb)]·2H(2)O}(n) (1), {[Co(btec)(0.5)(btmb)(H(2)O)]·3H(2)O}(n) (2), {[Cu(btec)(0.5)(btmb)]·H(2)O}(n) (3), {[Cu(4)(btc)(4)(btmb)(4)]·H(2)O}(n) (4), {[Co(3)(bta)(2)(btmb)(2)]·2H(2)O}(n) (5), [Co(Hbta)(btmb)](n) (6) (H(4)btec = 1,2,4,5-benzenetetracarboxylate, H(3)btc = 1,3,5-benzenetricarboxylate, H(3)bta = 1,2,4-benzenetricarboxylate and btmb = 4,4'-bis(1,2,4-triazol-1-ylmethyl)biphenyl), have been successfully synthesized under hydrothermal conditions. All these complexes were structurally determined by single-crystal X-ray diffraction, elemental analysis, IR, TGA and XRD. Crystal structural analysis reveals that 1 is the first example of an unusual 3D framework with (8(6)) topology containing a 2D molecular fabric structure. Complex 2 exhibits a 3D NbO network with (6(4)·8(2)) topology. In 3, Cu(II) ions are coordinated by anti-conformational btmb ligands to form left- and right-handed double helices, which are further bridged by the 4-connected btec(4-) anions to give a 3D porous network. Complex 4 presents a rare 3D gra network structure with (6(3))(6(9)·8) topology. 5 and 6 were obtained through controllable pH values of solution, 5 features a scarce binodal (3,8)-connected tfz-d framework with the trinuclear Co(II) clusters acting as nodes, whereas 6 has an extended 2D 4(4) grid-like layer and the adjacent 2D layers are interconnected by strong hydrogen bonding interactions into a 3D supramolecular framework. The structural diversities indicate that distinct organic acid ligands, the nature of metal ions and the pH value play crucial roles in modulating the formation of the resulting coordination complexes and the connectivity of the ultimate topological nets. Moreover, magnetic susceptibility measurement of 5 indicates the presence of weak ferromagnetic interactions between the Co(II) ions bridged by carboxylate groups.

The conformational bis-triazole ligand 4,4'-bis[(1,2,4-triazol-1- yl) methyl] biphenyl (btmb, 1), was successfully synthesized, and seven new coordination polymers, namely {M(oba)( btmb)}(n) [M = Cd2+ (2), Co2+ (3), Ni2+ (4), and Zn2+ (5)], {M(sdba)(btmb)}(n) [M = Co2+ (6) and Cd2+ (7)], and {[Cu(H(2)odpa)(btmb)(H2O)]center dot 2H(2)O}(n) (8), (H(2)oba = 4,4'-oxydibenzoic acid, H(2)sdba = 4,4'-sulfonyldibenzoic acid, and H(4)odpa = 4,4'-oxydiphthalic acid), have been synthesized by utilizing the btmb ligand and the polymers have been characterized in detail. Complexes 2-4 are isostructural exhibiting 2D-layer structures and can be described as (3,4)-connected networks with (4(2).6(3).8)(4(2).6) topological notation. Complex 5 shows 2D layers with left-and right-handed helical chains and has a (3,4)-connected net with (4.5(2))(4.5(3).7(2)) topology. Complexes 6 and 7 are isostructural and display 2D undulating networks with (4,4) sheets that are further packed through van der Waals interactions to generate a 3D supramolecular structure. Complex 8 also represents a 2D network with a 4(4)-sql net, which is extended into a 3D supramolecular framework by hydrogen-bonding interactions. The structural differences of these complexes demonstrate that the conformation of the btmb ligand and flexible aromatic polycarboxylate anions play critical roles in the formation of the resulting frameworks. Furthermore, their thermal properties have been studied by thermogravimetric analysis (TGA) and the TGA results reveal that the triazole-based frameworks have a high thermal stability, which suggests they are good candidates for the construction of more stable complexes. The photoluminescent properties of complexes 2, 5, and 7 have also been studied.

Via hydrothermal synthesis, the self-assembly of d(10) metal, 2,4'-dipyridylamine (L) and 1,3-adamantanediacetic acid (H(2)ADA) generated two unprecedented coordination polymers [Zn(ADA)(L)](n) (1) and [Cd(ADA)(L)(2)]. (2). Complex I possesses a novel I D looped-chain topology structure decorated with arms. Complex 2 shows an extended threaded framework involving 2D coordination layers of square (4(4)) topology with dangling ligands, which gives the novel (2D -> 3D) polythreaded array. To the best of our knowledge, complex 2 is the first example with four dangling arms coordinated in the axial sites of dinuclear nodes. In addition, both of the complexes show strong photoluminescence at room temperature, and may be good candidates for potential luminescence materials. (C) 2009 Elsevier B.V. All rights reserved.

Three new complexes, [Zn(dtb)(4,4′-bipy)]·5H2O (1), [Zn(dtb)(bpp)]·H2O (2) and [Zn(dtb)(phen)2]·CH3-CH2OH·H2O (3) (dtb = 5,5′-dithiobis(2-nitrobenzoic acid), 4,4′-bipy = 4,4′-bipyridine, bpp = 1,3-bi(4-pyridyl) propane, phen = 1,10-phenanthroline), have been constructed by dtb ligand and zinc salt in the presence of different assistant N-containing ligands under hydrothermal conditions. The structures of the complexes were established by single-crystal X-ray diffraction analysis. Although compounds 1 and 2 are both 2D networks, the cavities’ forms and pitch of helix are different. The structure of compound 3 shows a 1D helical chain, and is extended by the supermolecule interactions into a 2D framework. These neutral polymeric complexes exhibit structural and dimensional diversity due to the different coordination modes of the flexible dtb ligand and the effect of assistant ligands.

Compounds [Cu2(trans-oxen)(tp)]n·2nH2O (1·2nH2O), [{Cu2(trans-oxpn)(H2O)2}{Cu2(trans-oxpn)}(isophth)2]n·7nH2O (2·7nH2O) and [Cu2(trans-oxen)(phth)]n·2nH2O (3·2nH2O) [H2oxen = N,N′-bis(2-aminoethyl)oxamide, H2oxpn = N,N′-bis(3-aminopropyl)oxamide, tp = terephthalate, isophth = isophthalate and phth = phthalate] were obtained from the self-organization of trans-oxamidato-bridged dicopper(II) building blocks [Cu2(trans-L)]2+ (L = oxen or oxpn) and phenyldicarboxylate spacers with differently oriented carboxyl groups and their crystal structures determined. All the compounds consist of solvated water molecules and 2-D polymeric coordination networks containing rectangular, H-shaped mosaics and distorted rectangular grids for 1, 2, and 3, respectively. In addition, variegated hydrogen bonds involving solvated water molecules link the 2-D nets into 3-D frameworks. New bridging modes were discovered for the three isomeric phenyldicarboxylates. Magnetic calculations on 2·7nH2O showed that the planar oxamidato bridge transmits antiferromagnetic interactions between the Cu(II) ions.

The assembly of the ditopic N-donor ligands bpy, bpe or dapm and the building block [Cu(trans-oxpy)Cu](2+) (H(2)oxpy=N,N'-bis(2-pyridylmethyl)oxamide) gave rise to three 1-D coordination polymers [Cu-2(trans-oxpy)(bpy)(H2O)(2)](n)[NO3](2n). nH(2)O (bpy=4,4'-bipyridine) 1, [Cu-2(trans-oxpy)(bpe)(H2O)(2)](n)[NO3](2n). 3nH(2)O (bpe=1,2-di-4-pyridylethylene) 2 and [Cu-2(trans-oxpy)(dapm)(2)](n)[NO3](2n). 6nH(2)O (dapm=4,4'-diaminodiphenylmethane) 3 and their structures were determined by single crystal X-ray crystallography. The copper atoms, which are located in distorted square-based pyramidal environments in all the complexes, are bridged alternately by oxpy and a ditopic spacer ligand to form infinite chains with fine structures varying with the flexibility of the ligand. Furthermore, there are interchain pi...pi interactions in 1 and 2 between the pyridyl rings of oxpy and the spacers. The dinuclear unit [Cu(trans-oxpy)Cu](2+) displays an integrity in the assembly process. Variable temperature magnetic susceptibility measurements on 3 showed the presence of antiferromagnetic coupling interactions between the copper(II) ions bridged by oxpy. Thermal analyses indicated that dehydration occurred around 110 degreesC and these complexes are stable up to 230 degreesC.

A heterometallic assembly, [{Cd(en)2Ag(CN)2}{Ag(CN)2}]n, has been synthesized and structurally characterized. The 2D layered structure is constructed by interweaving the coordination chains of {Cd(en)2Ag(CN)2}+ containing CdNCAg linkage with the pseudo-metal wires formed by the anions [Ag(CN)2]− and Ag(I) of the chains through Ag–Ag interactions.

Two compounds with the composition [Cu2(trans-L)(suc)(H2O)2]n·2nH2O (L=oxap 1, oxen 2; suc=succinate) were obtained from the assembly of trans-oxamidato-bridged binuclear motif [Cu2(trans-L)]2+ and suc and their structures were determined by X-ray crystallography. Both compounds contain 1-D zigzag polymeric chains with the Cu(II) atoms alternately linked together by L and suc via covalent bonding interactions. Hydrogen-bonding interactions in them are abundant and very different. Their thermal properties were studied.

A three-dimensional coordination polymer [Ni(en)2Ag3(CN)5]n (en = 1,2-diaminoethane) was synthesized and characterized by X-ray crystallography. It crystallizes in the triclinic space group \(P\bar 1\),a = 7.520(2) Å, b = 8.194(2) Å, c = 8.426(2) Å, α = 65.35(3)°, β = 69.57(3)°, γ = 68.91(3)°, V = 428.0(2), Å3Z = 1. The 2D hexagonal grids are constructed using cyanides as bridges, and the Ag···Ag interactions between layers lead to a three-dimensional network.