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Zn(II) and Cd(II) coordination polymers constructed from a new angular bis-pyridyl-bis-amide ligand and naphthalene-1,4-dicarboxylic acid (1,4-H2NDC), {[Zn2(L)(1,4-NDC)2]·2H2O} [L = 4,4′-oxybis(N-(pyridin-3-ylmethyl)benzamide)], 1, and {[Cd2(L)(1,4-NDC)2]·EtOH}, 2, have been solvothermally synthesized and structurally characterized by using single-crystal X-ray diffraction. While complex 1 displays a 2D double layer with the rare (46·64)-5 L4 topology, complex 2 shows a 3D framework with a new (4·5·6)(45·55·69·7·8) topology. Both complexes 1 and 2 display luminescence properties and 2 exhibits a high sensitivity toward the detection of Fe3+ ions with a Ksv value of 1.9 × 104 M−1. The quenching effect can most probably be ascribed to the interactions between the metal ions and the amide carbonyl oxygen atoms.

One-pot solvothermal reactions of 2-aminopyridine, triethylorthoformate and sodium hydroxide with CuX (X = Br, and I) in dimethylformamide (DMF) and methanol (MeOH) afforded extended metal chains based on the linear tetracopper units, {[Cu4Br2(Dpyf)2]·DMF}n, 1, and [Cu4I2(Dpyf)2]n, 2, which were structurally identified by X-ray crystallography. Complexes 1 and 2 present closed-shell Cu(I)–Cu(I) interactions that are supported by formamidinate ligands, resulting in a face-to-side configuration and a face-to-face configuration, respectively, for the tetranuclear units. Complexes 1 and 2 represent the first example of one-dimensional (1D) coordination polymers that are based on linear tetracopper units. Moreover, complexes 1 and 2 can be regarded as copper(I) halide aggregates with the unique Cu4Br22+ and Cu4I22+ cations extending into a 1D zigzag chain and a looped chain, respectively. Complexes 1 and 2 show broad emissions at 570 and 549 nm, respectively, which can most probably be ascribed to 3d(Cu) → π* metal to ligand charge transfer. Reversible crystal-to-crystal transformation and luminescence change were observed for complex 1 upon solvent exchange, which can be regarded as a potential luminescent sensor for selective detection of water and methanol.

Solvothermal reactions of Cd(CH3COO)2 and 2,2′-(1,3-phenylene)-bis(N-pyridin-3-yl)acetamide (1,3-pbpa) with 1,3-phenylenediacetic acid (1,3-H2PDA), 4,4′-oxybis(benzoic acid) (4,4′-H2OBA) and 1,4-benzenedicarboxylic acid (1,4-H2BDC) afforded [Cd(1,3-pbpa)(1,3-PDA)]n, 1, [Cd(1,3-pbpa)(OBA)·2H2O]n, 2, and [Cd(1,3-pbpa)(1,4-BDC)(H2O)·EtOH·H2O]n, 3, respectively, which were structurally characterized as two-dimensional (2D) coordination polymers. Complexes 1 and 2 show the rare {84·122}{8}2-2,4L2 topology, whereas complex 3 adopts a new topology with a point symbol of {12}{4·125}{4}, which can be further simplified as the 44-sql topology and the 63-hcb topology, respectively. Desolvated product of 2 shows a moderate uptake of CO2 and a good selectivity over N2, which also exhibits a better H2 and CO2 sorption compared to the activated product of 1, indicating the effect of ligand type on the adsorption properties of 2D complexes with the 44-sql topology. Thermal gravimetric analysis (TGA) and the solid state luminescence properties of 1–3 have also been investigated.

Reactions of divalent metal salts with 4,4-oxybis(N-(pyridine-4-yl)-benzamide), L, and naphthalene-1,4-dicarboxylic acid (1,4-H2NDC) in various solvents gave [Zn(L)(1,4-NDC)·H2O]n, 1, [Cd(L)(1,4-NDC)(H2O)·MeOH]n, 2, and [Co(L)(1,4-NDC)(H2O)0.5·MeOH]n, 3, which have been structurally characterized. Complexes 1–3 show eight-fold interpenetrating frameworks with the dia topology, which exhibit porosities substantiated by CO2 adsorption, whereas 1 and 2 manifest stability in aqueous environments and show high selectivity toward sensing of mesitylene molecules and Fe3+ ions with low detection limits and good reusability up to five cycles.

Four coordination polymers constructed from the flexible isomeric bis-pyridyl-bis-amide (bpba) ligands, N,N′-di(3-pyridyl)suberoamide (L1) and N,N′-di(4-pyridyl)suberoamide (L2), and the auxiliary 1,4-naphthalenedicarboxylic acid (1,4-H2NDC), including [Co(L1)1.5(1,4-NDC)(H2O)]n, 1, [Co3(L1)1.5(1,4-NDC)3(EtOH)]n, 2, {[Co(L2)1.5(1,4-NDC)]·H2O}n, 3, and {[Co(L2)0.5(1,4-NDC)]·EtOH}n, 4, have been synthesized and structurally characterized by using single crystal X-ray crystallography. Complex 1 forms a two-dimensional layer with double edges and 2 exhibits a unique three-dimensional (3D) self-catenated framework with the (48.66.8)-6T60 topology, while 3 displays a 3D framework with the highest 5-fold interpenetration for the bnn topology and 4 shows a 3D 2-fold interpenetrated framework with the pcu topology. The donor atom positions of the L1 and L2 ligands and the identity of the solvents play important roles in determining the structural diversity. Moreover, irreversible structural transformation from 2 t...

Solvothermal reactions of Cd(II) salts and naphthalene-1,4-dicarboxylic acid (1,4-H2NDC) with bis(N-pyrid-3-ylmethyl)adipoamide, L1, and bis(N-pyrid-3-ylmethyl)suberoamide, L2, afforded three Cd(II) coordination polymers, {[Cd(L1)(1,4-NDC)(H2O)]·H2O}n, 1, {[Cd(L2)(1,4-NDC)]·2H2O}n, 2, and {[Cd2(L2)(1,4-NDC)2]·3H2O}n, 3, which have been structurally characterized using single-crystal X-ray crystallography. Complex 1 forms a 2D layer with 44-sql topology, whereas 2 and 3 are 3D frameworks with rare {32·62·72}{32·65·73}2-4,5T61 and unique {32·54}{34·46·58·66·74}-sqc776 topologies, respectively. Complex 2 undergoes reversible crystal-to-crystal transformation to 3, while irreversible structural transformations from 1 to 2 and 3 to 1 can be carried out by linker exchange. Reorientation of the amide oxygen atoms that results in the change of the ligand conformation is proposed for the initiation of the crystal-to-crystal transformation. Complex 3 represents a unique example of a coordination polymer that is able to undergo both crystal-to-crystal transformation and linker exchange.

The syntheses, structures and thermal properties of six coordination polymers based on semi-rigid N,N′-bis(3-pyridinyl)terephthalamide (L1), flexible N,N′-di(3-pyridyl)adipoamide (L2) and N,N′-di(3-pyridyl)suberoamide (L3) and auxiliary dicarboxylate ligands, [M(L1)(AIPA)·2H2O]n, (M = Ni, 1; Co, 2; H2AIPA = 5-acetamido isophthalic acid), [Ni(L2)(AIPA)(H2O)2]n, 3, [Co(L2)0.5(AIPA)(H2O)]n, 4, [Co(L3)(2,4-PDC)(H2O)]n (2,4-H2PDC = 2,4-pyridinedicarboxylic acid), 5, and [Co(L3)(5-Br-IPA)(H2O)]n (5-Br H2IPA = 5-bromoisophthalic acid), 6, are reported, which have been structurally characterized by X-ray crystallography. Complexes 1 and 2 are isomorphous, forming 3D nets with the new (4⋅6⋅8)(4⋅64⋅85) topology, which can be further simplified as self-catenated networks with the (424⋅64)-8T2 topology, while 3 is a 1D looped chain and 4 and 6 show 2D layers with the (42⋅63⋅8)(42⋅6)-3,4L83 and (44⋅62)-sql topologies, respectively. Moreover, complex 5 shows quadruple-strained helices formed by cobalt ions and L3 ligands, which are supported by 2,4-PDC2- anions to construct the rare single-walled metal-organic nanotubes that are supported by extensive N H --O and O H --O hydrogen bonds. The roles of ligand flexibility and the identity of the metal ion in the formation of 1–6 as well as their thermal properties are discussed.

A series of Co(II), Ni(II) and Cu(II) coordination polymers and dinuclear metallocycles containing 4-aminopyridine (4-ampy) and benzenedicarboxylate ligands, {[M(4-ampy)2(1,4-BDC)]&middot, H2O&middot, CH3CH2OH}n (M = Ni, 1a, Co, 1b, 1,4-H2BDC = benzene-1,4-dicarboxylic acid), {[Ni2(4-ampy)4(1,3-BDC)2]&middot, CH3CH2OH}n (1,3-H2BDC = benzene-1,3-dicarboxylic acid), 2, [M2(4-ampy)4(1,2-BDC)2] (M = Ni, 3a, Co, 3b, 1,2-H2BDC = benzene-1,2-dicarboxylic acid), [Co(4-ampy)2(1,3-BDC)]n, 4, {[Cu(4-ampy)2(1,4-BDC)] CH3CH2OH}n, 5a, and {[Cu(4-ampy)2(1,4-BDC)]&middot, H2O}n, 5b&middot, H2O, are reported, which were hydrothermally prepared and structurally characterized by using single crystal X-ray diffraction. Complexes 1a and 1b are isomorphous 1D zigzag chains, while 2 displays a concave&ndash, convex chain and 3a and 3b are dinuclear metallocycles that differ in the boding modes of the 1,2-BDC2&minus, ligands, forming a 3D and a 2D supramolecular structures with the pcu and sql topologies, respectively. Complex 4 exhibit a 1D helical chain and complexes 5a and 5b&middot, H2O are 1D linear and zigzag chains, in which the Cu2-1,4-BDC2&minus, units adopt the cis and trans configurations, respectively. A novel irreversible structural transformation due to cis&rarr, trans isomerization of the Cu2-1,4-BDC2&minus, units was observed in 5b&sdot, H2O and 5a upon water adsorption of the desolvated product of 5b&middot, H2O.

Solvothermal reactions of HgX2 salts with the new bis-pyridyl-bis-amide ligand 2,2′-(1,3-phenylene)-bis(N-(pyridin-3-yl)acetamide) (1,3-pbpa) in acetonitrile afforded the complexes [Hg(1,3-pbpa)X2]n (X = Cl, 1; Br, 2; I, 3), while the complexes [Hg(1,3-pbpa)X2·MeCN]n (X = Br, 4; I, 5) were obtained by layering solutions of HgX2 and 1,3-pbpa at room temperature. Complexes 1 and 2 are isostructural one-dimensional (1D) helical chains different from the 1D helical chain 3 in spans, which are 18.0, 18.3 and 29.1 A, respectively. Upon solvent adoption and removal, complexes 2 and 3 undergo reversible structural transformation into the 1D mesohelical chains 4 and 5 with spans of 29.1 and 29.9 A, respectively. Pyridyl ring rotation and amide group reorientation are proposed for the structural transformation accompanied by a simultaneous change in luminescence. The structural transformation in 2 and 4 represents a unique example of elastic 1D helical chains that show stretching during the process. The roles of halide anions in the structural changes and the luminescence properties of 1–5 are also discussed.

The synthesis, structures and properties of five new coordination polymers containing isomeric N,N′-di(pyridyl)suberoamide and polycarboxylate ligands, {[Cd(1,3-BDC)(L1)]·H2O}n [L1 = N,N′-di(3-pyridyl)suberoamide; 1,3-H2BDC = benzene-1,3-dicarboxylic Acid] 1; [Cd(5-OH-IPA)(L1)]n (5-OH-IPA = 5-hydroxyisophthalic Acid), 2; {[Cd3(1,3,5-BTC)2(L1)3(H2O)3]·8H2O}n (1,3,5-H3BTC = 1,3,5-benzenetricarboxylic Acid), 3; [Cd(5-Br-IPA)(L2)]n [L2 = N,N′-di(4-pyridyl)suberoamide; 5-Br-H2IPA = 5-bromoisophthalic Acid], 4; [Cd(5-tert-IPA)(L2)0.5]n (5-tert-H2IPA = 5-tert-butylisophthalic acid), 5, are reported, which have been characterized by single crystal X-ray diffraction. Complexes 1 and 2 show 2D double layers with the 3,5L2 topology and 3 reveals a 3D structure with the rare 3,4,4T90 topology. Complex 4 is a twofold interpenetrated 2D layer with a 2,6L1 topology and 5 shows a 3D coordination network with a rare 4,6T136 topology. In 5, the L2 ligand adopts a unique tetradentate bonding mode through two pyridyl nitrogen and two amide oxygen atoms. The structure-directing role roles of the substituent groups on the polycarboxylate ligands in determining the structural diversity are discussed. Their thermal and luminescent properties are also investigated.

The reactions of CuCl and CuBr with 2-amino-5-chloropyrimidine ( L-Cl ), 2-amino-5-bromopyrimidine ( L-Br ) and 2-amino-5-iodopyrimidine ( L-I ) in aqueous solutions of HCl and HBr afforded [CuCl 2 (H L-I ) · H 2 O] n , 1 , [CuBr 2 (H L-I ) · H 2 O] n , 2 , [CuCl 2 (H L-Br ) · H 2 O] n , 3 , [CuBr 2 (H L-Br ) · H 2 O] n , 4 , and [CuCl 2 (H L-Cl ) · H 2 O) n , 5 . Complexes 1 – 5 show 1D zigzag chains due to the zigzag arrangements of the bridging halide atoms. While the iodo atoms of the pyrimidyl rings in 1 and 2 are trans to the bridging halide anions and the Cu(I) ions are in a linear array, the chloro and bromo atoms of the pyrimidyl rings in 3 – 5 are cis to the bridging halide anions and the Cu(I) ions are in a zigzag fashion. The structural difference can most probably be ascribed to the identity of the halogen atoms. While the chloro and bromo atoms play the same role in the crystal structures, the iodo atom is distinct. X-ray crystallographic study and Hirshfeld surface analysis are invoked to investigate the structural differences.

Solvothermal reactions of HgX2 with 2,2′-(1,2-phenylene)-bis(N-pyridin-3-yl)acetamide, L, in ethanol afforded [Hg(L)X2]n (X = Cl, 1; Br, 2; I, 3), which are isostructural one-dimensional (1D) zigzag chains, while layering reactions of a ethanoic solution of L with a methanoic solution and an acetonitrile solution of HgI2, respectively, gave 1D helical chains [Hg(L)I2·MeOH]n, 4, and [Hg(L)I2·MeCN]n, 5. In marked contrast to 1 and 2, the iodide-containing 3 is able to exhibit reversible structural transformation with 4 and 5 by adsorption and desorption of methanol and acetonitrile, suggesting the importance of N–H---X and Hg---X interactions in the evaluation of structural transformation. Moreover, complexes 4 and 5 exhibit reversible crystal to crystal transformation triggered by solvent exchange. Complexes 3–5 represent a unique example that the solvents show a significant effect on folding and unfolding of the HgI2 single-stranded helical coordination polymers.

A series of coordination networks constructed from divalent metal ions, N,N′-di(3-pyridyl)adipoamide (L) and phenylenediacetate ligands, including [Co(L)0.5(1,2-pda)(H2O)]n (1,2-H2pda = 1,2-phenylenediacetic acid), 1, [Co(L)(1,4-pda)]n (1,4-H2pda = 1,4-phenylenediacetic acid), 2, [Ni2(L)2(1,2-pda)2(H2O)2·4.5H2O]n, 3, [Ni(L)(1,4-pda)(H2O)0.5·2.5H2O]n, 4, [Zn(L)0.5(1,2-pda)]n, 5, [CdBr(L)(1,2-pda)0.5]n, 6, and [CdI(L)(1,2-pda)0.5]n, 7, have been synthesized by hydrothermal reactions and structurally characterized by single crystal X-ray diffraction. Complexes 1, 2 and 5 adopt the (42,63,8)(42,6)-3,4L83, (42,67,8)(42,6)-3,5L2 and (42,63,8)(42,6)-3,4L83 topologies, respectively, while 3 and 4 show the (48,67)-6T2 and (48,67)-sqc26 topologies, respectively, and both 6 and 7 display the (412,63)-pcu topology. The L ligands in 3 adopt three different conformations, while the pda2− ligands in 5 adopts the rare cis-conformation and those in the other complexes exhibit the trans-conformation. Moreover, the pda2− ligands in complexes 1, 2 and 5 display the μ3 bonding mode to afford the 2D layer structures, in contrast to those in the other complexes that show the μ4 and/or μ2 bonding modes to form the 3D frameworks. The conformations of the L ligands are subject to the changes of metal ions and pda2− ligands, resulting in various types of structure for 1–7. Temperature-dependent PXRD patterns of complexes 1, 3 and 4 indicate that their structural transformations upon removal of the water molecules are irreversible. The emission spectra of 6 and 7 reveal that the lower electronegativity of the iodide relative to the bromide has a significant effect on the bathochromic shift.

The one-pot solvothermal reactions of 3- and 4-(aminomethyl)pyridine with triethyl orthoformate and Cu(O2CCH3)2 in methanol saturated with dinitrogen afforded the first examples of coordination polymers that are supported by dinitrogen, namely [Cu2.5(3-mpyf)(N2)1.5]n [3-Hmpyf = N,N′-bis(pyridine-3-ylmethyl)formamidine], 1, and {[Cu3(4-Hmpyf)(N2)3]·(CH3OH)}n [4-Hmpyf = N,N′-bis(pyridine-4-ylmethyl)formamidine], 2. The dinitrogen anions of 1 adopt the end-on-dinuclear (μ-η1:η1) bonding mode, resulting in a 4,4-connected binodal net with the new (53·73)2(54·82) topology, and those of 2 display both end-on-dinuclear and end-on-trinuclear (μ-η1:η1:η1) bonding modes, forming a 3,8-connected binodal net with the rare (53)4(58·64·78·84·94)2-3,8T16 topology.

By using a new flexible tetracarboxylic acid, bis(3,5-dicarboxyphenyl) adipoamide, H4L1, and its isomer, bis(2,5-dicarboxyphenyl)adipoamide, H4L2, three Mg(II) coordination polymers, {[Mg2(L1)(H2O)2]·2EtOH·3H2O}n, 1, [Mg2(L1)(H2O)8]n, 2, and {[Mg2(L2)(H2O)6]·H2O}n, 3, have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complexes 1 and 2 are the solvent ratio-dependent hydrothermally stable products. The tetracarboxylate ligand of complex 1 connects eight Mg(II) ions through nine oxygen atoms, resulting in a three-dimensional (3D) 5-connected uninodal net with a rare non-interpenetrating (44.66)-pcu-5-Pmna topology, whereas those of 2 and 3 link four Mg(II) ions through four oxygen atoms and six Mg(II) ions through six oxygen atoms, forming a 1D linear chain and a 3,6-connected 2-nodal 3D net having {4.62}2{42.610.83}-rtl topology, respectively. Complex 1 shows a series of structural transformations on heating to 200 °C and almost reversible structural transformation when the activated products were immersed in a mixture of ethanol and water or on hydrothermal. Likewise, complex 2 exhibits a reversible structural transformation on heating/hydrothermal, while 3 exhibits irreversible structural transformations. All three complexes exhibit blue light emissions, with that of complex 3 being much more intense.

Ten coordination polymers constructed from divalent metal salts, polycarboxylic acids, and bis-pyridyl-bis-amide ligands with different donor atom positions and flexibility are reported. They were structurally characterized by single-crystal X-ray diffraction. The ten coordination polymers are as follows: (1) {[Ni(L1)(3,5-PDA)(H2O)3]·2H2O}n (L1 = N,N′-di(3-pyridyl)suberoamide, 3,5-H2PDA = 3,5-pyridinedicarboxylic acid); (2) {[Ni2(L1)2(1,3,5-HBTC)2(H2O)4]·H2O}n (1,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid); (3) {[Ni(L2)(5-tert-IPA)(H2O)2]·2H2O}n (L2 = N,N′-di(3-pyridyl)adipoamide, 5-tert-H2IPA = 5-tert-butylisophthalic acid); (4) [Ni(L3)1.5(5-tert-IPA)]n (L3 = N,N′-di(4-pyridyl)adipoamide); (5) [Co(L1)(1,3,5-HBTC)(H2O)]n; (6) {[Co3(L1)3(1,3,5-BTC)2(H2O)2]·6H2O}n; (7) [Cu(L4)(AIPA)]n (L4 = N,N′-bis(3-pyridinyl)terephthalamide, H2AIPA = 5-acetamido isophthalic acid); (8) {[Cu(L2)0.5(AIPA)]·MeOH}n; (9) {[Zn(L4)(AIPA)]·2H2O}n; and (10) {[Zn(L2)(AIPA)]·2H2O}n. Complex 1 forms a 1D chain and 2 is a two-fold interpenetrated 2D layer with the sql topology, while 3 is a 2D layer with the hcp topology and 4 shows a self-catenated 3D framework with the rare (42·67·8)-hxg-d-5-C2/c topology. Different Co/1,3,5-H3BTC ratios were used to prepare 5 and 6, affording a 2D layer with the sql topology and a 2D layer with the (4·85)2(4)2(83)2(8) topology that can be further simplified to an hcp topology. While complex 7 is a 2D layer with the (42·67·8)(42·6)-3,5L2 topology and 8 is a 2-fold interpenetrated 3D framework with the pcu topology, complexes 9 and 10 are self-catenated 3D frameworks with the (424·64)-8T2 and the (44·610·8)-mab topologies, respectively. The effects of the identity of the metal center, the ligand isomerism, and the flexibility of the spacer ligands on the structural diversity of these divalent coordination polymers are discussed. The luminescent properties of 9 and 10 and their photocatalytic effects on the degradation of dyes are also investigated.

The synthesis, structures and properties of six coordination networks based on N,N′-di(4-pyridyl)suberoamide (L) and angular dicarboxylate ligands, {[Co(L)(MBA)]·2H2O}n (H2MBA = diphenylmethane-4,4′-dicarboxylic acid), 1, {[Co(L)0.5(MBA)]·CH3OH}n, 2, [Co(L)0.5(MBA)]n, 3, {[Co2(L)(OBA)2]·7CH3OH}n [H2OBA = 4,4′-oxybis(benzoic acid)], 4, {[Co(L)(hfipbb)]·2H2O}n [H2hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid)], 5, and {[Co(L)(SDA)]·H2O}n (H2SDA = 4,4′-sulfonyldibenzoic acid), 6, are reported. Complex 1 is a 1D → 2D polycatenane derived from the helical channels, whereas both complexes 2 and 3 show 2D layers with the (42·68·8·104)(4)2-2,6L1 topology, which are further entangled to form a 2-fold 2D → 2D interpenetration network and a 2D → 3D inclined polycatenation network, respectively, and complex 4 shows a 3-fold 3D → 3D interpenetration network with the (412·63)-pcu topology. The unusual topological features of 5 and 6 consist of 2- and 3-fold interpenetrated layers with the (44·62)-sql topology, which are further catenated to the two such adjacent sheets in parallel and uniform fashions to give 2D → 3D polycatenated networks. Complexes 1, 5 and 6 represent unique examples that the angular dicarboxylate ligands show significant effect on the degree of interpenetration of polycatenation coordination networks with interpenetrating modes. The CO2 capture is preferable to N2 and H2 in the gas sorption for the desolvated product of 4.

New types of organic copolymer–inorganic hybrid material zinc-phosphonate-phosphates are prepared with amines as templates. Notably, crystalline samples are obtained not with traditional methods but with simple reactions. Moreover, the samples are provided with the potential application as superior performance catalyst supports.

Four one-dimensional (1D) mercury(II) halide coordination polymers have been synthesized by using a semi-rigid N-donor ligand, 2,2&prime, (1,4-phenylene)-bis(N-(pyridin-3-yl)acetamide) (1,4-pbpa). While [Hg(1,4-pbpa)Cl2&middot, CH3OH]n, 1, forms a sinusoidal chain, the complexes [Hg(1,4-pbpa)X2]n (X = Cl, 2, Br, 3, I, 4) are helical. The sinusoidal 1 undergoes reversible structural transformation with helical 2 upon removal and uptake of CH3OH, which was accompanied with the conformation adjustment of the 1,4-pbpa ligand from trans anti-anti to trans syn-anti. Pyridyl ring rotation of the 1,4-pbpa ligand that results in the change of the ligand conformation is proposed for the initiation of the structural transformation.

The simultaneous removal of SO2 and NO was investigated with the activated carbon from sewage sludge (referred as ACS) modified by chitosan (referred as CS).The effects of CS loading and operating conditions on the simultaneous removal of SO2 and NO were analyzed. The results indicate that compared with the ACS, impregnating CS results in significant increase in SO2 or NO removal. Relative humidity enhances SO2 adsorption capacities, but not for NO. The SO2 adsorption capacities of the CS / ACS show no obvious decrease at small amount of NO in the feed. However, higher amounts of NO reduce the SO2 adsorption capacities. The opposite phenomenon appears for NO when a small amount of SO2. So a competitive sorption consists between NO and SO2. Simultaneous adsorptions for NO and SO2 is due to more active sites from CS.

Heavy metal leaching limits activated carbon from sewage sludge (referred as ACS) to be used for wastewater treatment. Cr and Cd leaching from ACS exceed the permitted values. The leaching content of Cr and Cd decrease much with depositing ACS with chitosan (CS),below the permitted values. This is mainly due to the bind of Cr and Cd with the much group –NH2 of CS. The effects of initial dye concentration, pH and contact time had been studied. The dye adsorbed can act as a supple complexion agent with increasing initial dye concentration, increase the affinity for Cr and Cd. For Cd, the amount leaching of CS/ACS or ACS remains content with pH.The amount leaching of Cr decreases when the pH from 1 to 5 and then increases above the pH of 6.0. The contact time has no important influence on the leaching contents of Cr or Cd.

Reactions of N,N’-bis(pyridine-4-yl)formamidine (4-Hpyf) with HgX2 (X = Cl, Br, and I) afforded the formamidinate complex {[Hg(4-pyf)2]·(THF)}n, 1, and the formamidine complexes {[HgX2(4-Hpyf)]·(MeCN)}n (X = Br, 2; I, 3), which have been structurally characterized by X-ray crystallography. Complex 1 is a 2D layer with the {44·62}-sql topology and complexes 2 and 3 are helical chains. While the helical chains of 2 are linked through N–H···Br hydrogen bonds, those of 3 are linked through self-complementary double N–H···N hydrogen bonds, resulting in 2D supramolecular structures. The 4-pyf- ligands of 1 coordinate to the Hg(II) ions through one pyridyl and one adjacent amine nitrogen atoms and the 4-Hpyf ligands of 2 and 3 coordinate to the Hg(II) ions through two pyridyl nitrogen atoms, resulting in new bidentate binding modes. Complexes 1–3 provide a unique opportunity to envisage the effect of the halide anions of the starting Hg(II) salts on folding and unfolding the Hg(II) coordination polymers. Density function theory (DFT) calculation indicates that the emission of 1 is due to intraligand π→π * charge transfer between two different 4-pyf- ligands, whereas those of 2 and 3 can be ascribed to the charge transfer from non-bonding p-type orbitals of the halide anions to π * orbitals of the 4-pyf- ligands (n→π *). The gas sorption properties of the desolvated product of 1 are compared with the Cu analogues to show that the nature of the counteranion and the solvent-accessible volume are important in determining their adsorption capability.

Poly(methylmethacrylate)(PMMA)/oxymethylene-linked polyoxyethylene multi-block polymer(Om-POEn, where n represents number of unit CH2CH2O) blend based composite electrolyte films containing different lithium salt concentration and nanofillers' content are prepared using solvent evaporation technique. The interaction of polymer–salt complex has been confirmed using FTIR spectral studies. The figuration of CPE was studied by XRD. Ionic conductivity and thermal behavior of the CPEs were studied with various salt concentrations, temperature, and nanofillers' content. The surface structure of the CPE is also investigated using scanning electron microscopy. The high room temperature ionic conductivity, transmittivity in the visible region, and thermal stability make these CPEs potential candidates as solid-like electrolytes for electrochemical devices. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007

A star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized, and its corresponding gel polymer electrolyte based on lithium perchlorate and plasticizers EC/PC with the character being colorless and highly transparent has been also prepared. The polymer host was characterized and confirmed to be of a star network and an amorphous structure by FTIR, 1H NMR and XRD studies. The polymer host hold good mechanical properties for pentaerythritol cross-linking. Maximum ionic conductivity of the prepared polymer electrolyte has reached 8.83×10−4 S·cm−1 at room temperature. Thermogravimetry (TG) of the polymer electrolyte showed that the thermal stability was up to at least 150 °C. The gel polymer electrolyte was further evaluated in electrochromic devices fabricated by transparent PET-ITO and electrochromically active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolyte as ionic conductor material in electrochromic devices.

The high quality TiO 2 , MoO 3 -doped WO 3 electrochromic film was prepared by the sol–gel method for the first time. The sol, which has hydrogen peroxide (H 2 O 2 ) and oxalic acid (H 2 C 2 O 4 ), was very stable at room temperature and quite suitable for the deposition of films. The WO 3 electrochromic film prepared from this doped sol had excellent performance, such as short response time, no cracks, good adhesion to the substrate, high coloring efficiency and longevity of service.

The layered amorphous and crystalline samples of zirconium [ N -(phosphonomethyl)morpholine-phosphate] Zr(HPO 4 )[O 3 PCH 2 N(CH 2 CH 2 ) 2 O]· n H 2 O (1a, 2a), zirconium [ N -(phosphonomethyl)iminodiacetic acid-phosphate] Zr(HPO 4 )[O 3 PCH 2 N(CH 2 CO 2 H) 2 ]· n H 2 O (1b, 2b) and zirconium [ N , N -di(phosphonomethyl) acetic acid] Zr[(O 3 PCH 2 ) 2 NCH 2 CO 2 H]· n H 2 O (1c, 2c) were synthesized for the first time with zirconium oxychloride, sodium dihydrogen phosphate and H 2 O 3 PCH 2 N(CH 2 CH 2 ) 2 O, H 2 O 3 PCH 2 N(CH 2 CO 2 H) 2 or (H 2 O 3 PCH 2 ) 2 NCH 2 CO 2 H in the absence and presence of hydrofluoric acid. The samples were comparatively characterized by XRD, IR, TG and elemental analysis. XRD data showed that the crystalline samples 2a, 2b and 2c are highly crystalline with interlayer spacings of 1.606, 1.538 and 1.239 nm, respectively. The amorphous and crystalline samples lost nearly the weight calculated for their organic component over the same broad temperature range of 172–664, 184–680 and 176–668 °C, respectively. XPS data indicated that the coordination bonds formed between nitrogen and palladium in the palladium complexes. Their palladium complexes possessed good activities for the hydrogenation of the carbon–carbon double bond. The catalytic activities of the palladium complexes of amorphous 1a, 1b and 1c is 1.5–3.1 times as high as that of the palladium complexes of crystalline 2a, 2b and 2c.

Zirconium (benxyldiethylammoniomethylphosphonate chloride)phosphate Zr(HPO4)2-x (O3PCH2N+Et2 CH2ph-Cl−)x-H2O, (0.25 < x < 0.75, ZBEPC-ZP) were prepared for the first time and characterized by IR andelemental analyses. ZBEPC-ZP catalyzed some typical PTC reactions in L/S/L phases were carried out to give good results. ZBEPC-ZP can be easily separated from the reaction mixture and recovered about 70–100%, and can be reused and did not show any change in activity after 10 cycles.

A series of 4-hydroxybenzene acrylic acid derivatives were designed and synthesized based on the ferulic acid of natural active ingredients. The tested compound 5a, 5f and 6a have significant anti-inflammatory activity with suppression rates of 45.29%, 44.75% and 24.11%, respectively, compared with that of indomethacin, and their cardiac toxicity was not observed. The structure-function relationship shows that the p-hydroxyl group on the α-position benzene ring, particularly if acetylated, contributes to the considerable anti-inflammatory activity; that the carboxyl group on the double bond, if esterified, also contributes to the anti-inflammatory activity; that the p-methylsulfonyl group on the other benzene ring, whose introduction is due to the COX-2 selectivity, also contributes to anti-inflammatory activity surprisingly.

The treatment of α-bromo-α,β-unsaturated esters with FSO2CF2CO2Me and CuI in DMF/HMPA constitutes a new synthetic scheme for the preparation of α-trifluoromethyl-α,β-unsaturated esters.

The treatment of α-bromo-α,β-unsaturated esters with FSO2CF2CO2Me and CuI in DMF/HMPA constitutes a new synthetic scheme for the preparation of α-trifluoromethyl-α,β-unsaturated esters.

The trifluoromethylation of (Z)/(E)-tert-butyl (4S)-4-(2'-ethoxycarbonyl-2'-bromoprop-1'-enyl)-2,2-dimethyloxazolidine-3-carboxylate (4), which is derived from chiral serine aldehyde, yields α-trifluoromethyl-α,β-unsaturated ester 1. Compound 1 is used as a key intermediate for the synthesis of a number of 2',3'-dideoxy-2'-trifluoromethyl-N-azanucleosides.

A random copolymer P(VAc-MMA) was synthesized via seeded emulsion copolymerization with vinyl acetate (VAc) and methyl methacrylate (MMA) as monomers, and the polymer electrolytes comprising blend of corresponding copolymer P(VAc-MMA) as a host polymer and LiClO4 as a dopant were prepared by solution casting technique. Performances of the synthesized copolymer and prepared polymer membrane and electrolyte were studied by FTIR, XRD, TG, DSC, mechanical testing and AC impedance. According to the study of FTIR and DSC, it was found that P(VAc-MMA) had been formed. XRD indicates that the amorphous nature in copolymer increased with increasing the ratio of VAc in monomers, resulting in expedite migration of ions. The polymer electrolytes based on P(VAc-MMA) possess excellent thermal stability, fine mechanical performance and high ionic conductivity. The maximum ionic conductivity value was found to reach 1.27 × 10-3S · cm-1 at 25°C. The temperature dependence of the polymer electrolyte complexes appeared to ob...

An amorphous, colorless, and highly transparent star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized from the poly(ethylene glycol) (PEG), pentaerythritol, and dichloromethane by Williamson reaction. FTIR and 1 H-NMR measurement demonstrated that the polymer repeating units were C(CH2―OCH2O―(CH2CH2O)m―CH2O―(CH2CH2O)n―CH2O)4. The polymer host held well mechanical properties for pentaerythritol cross-linking. The gel polymer electrolytes based on Lithium perchlorate (LiClO4) and ethylene carbonate/propylene carbonate (EC/PC) were prepared and characterized by AC impedance spectroscopy and thermogravimetry (TG), the results showed thermal stability up to at least 150°C and ionic conductivity reaching 8.83 × 10 −4 S·cm −1 at room temperature. The gel polymer electrolytes were further evaluated in electrochromic devices (ECD) fabricated by transparent PET-ITO and electrochromic active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolytes as ionic conductor material in ECD.