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ABSTRACT: Three inorganic-organic hybrid solids based on tetravanadate polyanions, {V(4)O(12)}(4-) and cucurbituril, Me(10)Q[5] and Q[5], namely (NH(4))(4)[(V(4)O(12))·(Me(10)Q[5]@0.5H(2)O)(2)]·∼13H(2)O (1), Li(4)(H(2)O)(5)[(V(4)O(12))·(Me(10)Q[5]@H(2)O)(2)]·∼20H(2)O (2), and Na(4)(H(2)O)(2)[(V(4)O(12))·(Q[5])(2)]·∼15H(2)O (3), have been synthesized under hydrothermal conditions. In the structure of compound 1, two {Me(10)Q[5]@0.5H(2)O} moieties connect to one {V(4)O(12)}(4-) cluster through an NH(4)(+) counter-cation to form a trimer unit, which further forms a three-dimensional (3D) supramolecular architecture via extensive hydrogen bonds (H-bonds). Compound 2 contains a one-dimensional (1D) covalently bonded chain structure built by alternate {Me(10)Q[5]@H(2)O} moieties and {Li(2)O(4)(H(2)O)(3)}(2+) dimer units. The anionic {V(4)O(12)}(4-) units bond to every another {Li(2)O(4)(H(2)O)(3)}(2+) dimer unit sitting on the chain through multi-uncoordinated water molecules via H-bonds. Compound 3 is built from {V(4)O(12)}(4-) clusters, Q[5], and sodium cations into a two-dimensional (2D) covalent wavy structure, showing interesting connection between the building units, which is packed into 2D through plentiful H-bonds. It has been found that the cations dramatically affect the coordination of the tetravanadate polyanion and cucurbituril.
Dalton Transactions 06/2012; 41(33):10080-4. · 3.84 Impact Factor
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ABSTRACT: Two anionic metal-organic frameworks were successfully prepared based on pre-designed flexible multicarboxylate ligands and indium cations. Owing to the flexibility of the bridging organic linkers, which could not themselves sustain the frameworks, both of the frameworks showed thermal instability and shrinkage after removal of guest solvent molecules. Inspired by bamboo, we used a guest-dependent approach to tune the permanent porosity of the MOFs. In this approach, several tetraalkyammonium cations of different sizes were introduced into the channels by cation exchange to act as partitions and to support the main frameworks. This approach significantly enhanced the stability of the framework and its permanent porosity. Moreover, the gas-adsorption properties (such as gate sorption, hysteresis, and selectivity) of the MOFs were also modulated by the judicious choice of guest cations.
Chemistry 04/2012; 18(25):7896-902. · 5.93 Impact Factor
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ABSTRACT: A series of four coordination polymers showing entangled architectures based on cobalt and mixed N-donor/O-donor ligands, namely [Co(4,4'-BPIPA)(TP)]·2DMF (1), [Co(4,4'-BPIPA)(2,6-NDC)(DMF)]·DMF (2), [Co(4,4'-BPIPA)(2,6-NDC)]·2DMF (3) and [Co(4,4'-BPIPA)(4,4'-BPDC)]·2DMF (4) (4,4'-BPIPA = N,N'-bis-4-pyridinyl-isophthalamide, TP = terephthalic acid, 2,6-NDC = 2,6-naphthalenedicarboxylic acid, 4,4'-BPDC = 4,4'-biphenyldicarboxylic acid), have been synthesized under solvothermal conditions. Complex 1, containing 4,4'-BPIPA and relatively short dicarboxylate ligands (TP), exhibits two-dimensional (2D) two-fold interpenetration of double wavy 4(4)-sql nets. Complex 2 displays interesting 2D→3D parallel polycatenation of undulated 2D 4(4)-sql layers built by 4,4'-BPIPA and moderate dicarboxylate ligands (2,6-NDC). Complexes 3 and 4, although constructed of dicarboxylate ligands with different lengths (moderate 2,6-NDC and long 4,4'-BPDC), possess similar 3-fold interpenetration of identical self-catenated single nets with 6(5)·8-mok topologies. It has been found that the length of the dicarboxylate ligands plays a key role of module-matching in the self-assemblies of complexes 1-4. Moreover, the effect of the conformations of 4,4'-BPIPA, which can be controlled by tuning reaction temperatures, is also discussed.
Dalton Transactions 01/2012; 41(14):4146-52. · 3.84 Impact Factor
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ABSTRACT: Two isostructural organic-inorganic hybrid solid materials based on cucurbituril derivatives and polyoxometalates, {[K(2)(H(2)O)(2)Na(2)(H(2)O)(2)Na(2)(H(2)O)(6)](P(2)W(18)O(62))(Me(10)Q(5))(2)}·~7H(2)O (1) and {[Rb(2)(H(2)O)(2)Na(2)(H(2)O)Na(2)(H(2)O)(4)](P(2)W(18)O(62))(Me(10)Q(5))(2)}·~8H(2)O (2), which exhibit reversible photochromic properties as well as excellent photocatalytic activities toward the degradation of methyl orange (MO) and rhodamine-B (RB) under visible light irradiation, are reported.
Chemical Communications 11/2011; 48(5):669-71. · 6.17 Impact Factor
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ABSTRACT: We describe two cobalt metal-organic frameworks built by amide derivative and organodicarboxyl co-ligands, displaying 3-fold interpenetration of 6(5).8-mok nets which are 4-connected self-catenated nets described theoretically in the early nineties.
Chemical Communications 06/2011; 47(21):5982-4. · 6.17 Impact Factor
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ABSTRACT: A water insoluble cucurbit[6]uril-polyoxometallates (CB[6]-POMs) composite assembled from α-Keggin type polysilicontungstate anions and macrocycle cucurbit[6]uril (CB[6]) via hydrogen bonding has been synthesized as visible light active photocatalyst. The physical and photocatalytic properties of such photocatalyst have been fully characterized by PXRD, FTIR, TG, XPS, and UV/vis diffuse reflectance spectra. The catalyst shows a good photocatalytic activity towards the degradation of methyl orange (MO) under visible light irradiation and displays good reproducibility of photocatalytic degradation by a simple recycled procedure without obvious loss in catalytic activity, which is of great significance for practical use of the photocatalyst. In the photodegradation process, the {Ni-CB[6]}(n) chain of the photocatalyst acts as sensitizer and can be induced by visible light, meanwhile the POMs chain of the photocatalyst acts as electron acceptor and deposits the electron in its LUMO. The effects of various experimental parameters and the proposed mechanisms are discussed in detail.
Journal of hazardous materials 02/2011; 186(1):948-51. · 4.14 Impact Factor
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ABSTRACT: A series of coordination polymers with anionic, cationic, and neutral metal-carboxylate frameworks have been synthesized by using a flexible tetrapodal ligand tetrakis[4-(carboxyphenyl)oxamethyl] methane acid (H(4)X). The reactions between divalent transition-metal ions and H(4)X ligands gave [M(3)X(2)]·[NH(2)(CH(3))(2)](2)·8DMA (M = Co (1), Mn (2), Cd(3)) which have anionic metal-carboxylate frameworks with NH(2)(CH(3))(2)(+) cations filled in channels. The reactions of trivalent metal ions Y(III), Dy(III), and In(III) with H(4)X ligands afforded cationic metal-carboxylate frameworks [M(3)X(2)·(NO(3))·(DMA)(2)·(H(2)O)]·5DMA·2H(2)O (M = Y(4), Dy(5)) and [In(2)X·(OH)(2)]·3DMA·6H(2)O (6) with the NO(3)(-) and OH(-) serving as counterions, respectively. Moreover, a neutral metal-carboxylate framework [Pb(2)X·(DMA)(2)]·2DMA (7) can also be isolated from reaction of Pb(II) and H(4)X ligands. The charged metal-carboxylate frameworks 1-5 have selectivity for specific counterions in the reaction system, and compounds 1 and 2 display ion-exchange behavior. Moreover, magnetic property measurements on compounds 1, 2, and 5 indicate that there exists weak antiferromagnetic interactions between magnetic centers in the three compounds.
Inorganic Chemistry 02/2011; 50(6):2264-71. · 4.60 Impact Factor
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ABSTRACT: One-dimensional (1D) homochiral nickel coordination polymers [Ni(3)(bpdc)(RR-L)(2)·(DMF)](n) (2R, RR-L = (R,R)-(-)-1,2-cyclohexanediamino-N,N'-bis(3-tert-butyl-5-(4-pyridyl)salicylidene), bpdc = 4,4'-biphenyldicarboxylic acid) and [Ni(3)(bpdc)(SS-L)(2)·(DMF)](n) (2S, SS-L = (S,S)-(-)-1,2-cyclohexanediamino-N,N'-bis(3-tert-butyl-5-(4-pyridyl)salicylidene) based on enantiopure pyridyl-functionalized salen(Ni) metalloligand units NiL ((1,2-cyclohexanediamino-N,N'-bis(3-tert-butyl-5-(4-pyridyl)salicylidene))Ni(II)) have been synthesized and characterized by microanalysis, IR spectroscopy, solid-state UV-vis spectroscopy, thermogravimetric analysis (TGA), circular dichroism (CD) spectroscopy, cyclic voltammetric measurement, and powder and single crystal X-ray diffraction. Each NiL as unbridging pendant metalloligand uses one terminal pyridyl group to coordinate achiral unit (nickel and bpdc(2-)) building a helical chain, while the other pyridyl group remains uncoordinated. Both 2R and 2S contain left- and right-handed helical chains made of the achiral building blocks, while the NiL as remote external chiral source is perpendicular to the backbone of the helices. The nickel coordination polymers 2R and 2S containing unsaturated active nickel center in metalloligand NiL can be used as self-supported heterogeneous catalysts. They show catalytic activity comparable with their homogeneous counterpart in alkene epoxidation and exhibit great potential as recyclable catalysts.
Inorganic Chemistry 02/2011; 50(6):2191-8. · 4.60 Impact Factor
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ABSTRACT: Quartz slides bearing layers of a palladium azopyridine complex are seen to liberate catalytic amounts of a soluble active palladium species which can be used for Suzuki coupling.
Chemical Communications 10/2010; 46(40):7584-6. · 6.17 Impact Factor
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ABSTRACT: A pcu network can be ordered through trigonal bipyramidal nanocages as secondary building blocks, which have the striking feature of hydrophilic affinity to the polar molecules and π-π interactions for aromatic molecules.
Chemical Communications 10/2010; 46(44):8439-41. · 6.17 Impact Factor
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ABSTRACT: A series of Pt nanoparticles (NPs) smaller than 3 nm were successfully encapsulated in dendrimer/SBA-15 organic and inorganic hybrid composite. The obtained catalysts were characterized by XPS, XRD and TEM. The results of XPS and XRD indicate the existence of Pt NPs in the hybrid matrix. TEM images display the Pt NPs with narrow size distribution are monodispersed in SBA-15 channels. Catalytic property of the supported Pt catalysts was investigated in inorganic (ferricyanide to ferrocyanide by thiosulfate) and organic (p-nitrophenol to p-aminophenol by sodium borohydride) electron transfer (redox) reactions. In both cases, the reduction reactions followed smoothly and the catalysts showed excellent catalytic activity. Moreover, the catalysts can be easily separated and reused several times preserving good catalytic performance.
Journal of Colloid and Interface Science 10/2010; 353(1):149-55. · 3.07 Impact Factor
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ABSTRACT: A series of tartrazine-lanthanide dye compounds has been synthesized and characterized. Structural studies reveal that the light rare-earth elements La, Ce, Pr and Nd form coordination compounds with tartrazine ligands in a 1:1 ratio and result in 1-D 'fish-bone' chain-like structures having uncoordinated organosulfonate groups on each side of the chain. However, reactions of tartrazine and heavy rare-earth elements Ho, Er, Tm and Yb, in the presence of auxiliary 1,10-phenanthroline, give new 1-D coordination polymers in which uncoordinated organosulfonate groups are located on the same side of the chains. The tartrazine ligands display similar but slightly different coordination modes in both types of structures and the 1,10-phenanthroline plays a vital role in the formation of heavy rare-earth dye compounds. Based on the knowledge of their structures, the light rare-earth dye compounds were utilized to assemble with positively-charged PEI into multilayer thin films by means of layer-by-layer depositions. The as-synthesized thin films showed enhanced stability and consistency on solid surfaces.
Dalton Transactions 10/2010; 39(45):10967-73. · 3.84 Impact Factor
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Berichte der deutschen chemischen Gesellschaft 07/2010; 2010(24):3842 - 3849. · 2.94 Impact Factor
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ABSTRACT: The layer-by-layer (LbL) assembled thin films containing tetraamino-thiacalix[4]arenes (1) and tetraamino-calix[4]arenes (2) were used as nanoreactor to synthesize in situ Ag nanoparticles (Ag NPs). UV-vis spectra and AFM images demonstrate that Ag NPs are included in the (1/Ag NPs)(n) and (2/Ag NPs)(n) multilayer films. The silver ions are absorbed through cation-pi interaction and calix[4]arene-metal ion coordination interaction and are reduced into Ag NPs by calix[4]arenes. TEM images indicated that Ag NPs within aminocalix[4]arene multilayers were highly dispersed and uniform. Moreover, the mean size of Ag NPs is smaller than 10 nm.
Journal of Colloid and Interface Science 09/2009; 341(2):320-5. · 3.07 Impact Factor
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ABSTRACT: Ten coordination compounds based on a sulfonated monoazo dye, formulated as M(H(2)O)(2)(4,4'-abs)(2) (M = Mn , Co , Cu , Zn , Cd and Pb ; 4,4'-abs = 4-aminoazobenzene-4'-sulfonic anion), Ag(4,4'-abs) (), [Ln(H(2)O)(phen)(2)(4,4'-abs)(3)].3H(2)O (Ln = Gd , Tb , and Ho ; phen = 1,10-phenanthroline), as well as the parent ligand L [(4,4'-Habs)(2).4H(2)O] and precursor NaL.HL [Na(4,4'-abs)(4,4'-Habs)] were successfully isolated. Structural analyses revealed that the structures of compounds, and vary according to the coordination geometries of the metal ions, and vary from double-strand chain structures () to a 3-D pillared-layer framework to mononuclear complexes. The double-strand chain structures of are isostructural, and are built on octahedral metal centers and double bridging 4,4'-abs ligands coordinating via terminal N- and O-donors. The silver-containing compound displays a pillared-layer structure constructed from 4.8(2) silver sulfonate nets pillared by the linear backbones of 4,4'-abs ligands. Compounds , which are also isostructural, possess mononuclear structures consisting of a metal cation, three 4,4'-abs anions, two auxiliary phen ligands, one aqua ligand and three non-coordinated water molecules. Evidence on two series of isostructural compounds indicates that structures of d- and f-block metal derivatives are dominated by the coordination mode of the ligands. The surface chemistry of compound has been investigated based on the LBL (layer-by-layer) technique. The as-synthesized multilayer films with different composite components exhibit different surface behaviours.
Dalton Transactions 04/2009; · 3.84 Impact Factor
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ABSTRACT: Three supramolecular compounds constructed from decamethylcucurbit[5]uril (Me(10)Q(5)) and decavanadate [H(2)V(10)O(28)](4-) were synthesized and characterized.
Dalton Transactions 03/2009; · 3.84 Impact Factor
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ABSTRACT: A novel pentadecatungstate, [H 6Ce 2(H 2O)Cl(W 5O 18) 3] (7-) ( 1), constructed by a dinuclear cerium unit and 15-member ring WO 6 units was prepared and characterized by single-crystal X-ray diffraction. Polyanion 1 exhibits blue photoluminescence with an emission maximum at 488 nm, which is characteristic of cerium(III) transitions from 5d to (2)F 5/2 states. Furthermore, the study of the electrochemical property investigation of 1 shows two reversible redox peaks ascribing to two-electron processes.
Inorganic Chemistry 08/2008; 47(13):5612-5. · 4.60 Impact Factor
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ABSTRACT: Three lanthanide coordination polymers constructed from infinite rod-shaped secondary building units (SBUs), [Nd(2)(H(2)O)(2)(cis-chdc)(2)(trans-chdc)]2H(2)O (1), Nd(2)(H(2)O)(4)(trans-chdc)(3) (2), and [Sm(2)(H(2)O)(2)(cis-chdc)(trans-chdc)(2)]4H(2)O (3) (chdcH(2)=1,4-cyclohexanedicarboxylic acid), were hydrothermally synthesized and structurally characterized. The structures of 1-3 are modulated by different ratios of the cis and trans configurations of chdc(2-) ligands, which was achieved by temperature control in the hydrothermal reactions. Crystal-structure analysis revealed that 1 is a four-connected pcu-type rod packing network built from cross-linking of rod-shaped neodymium-oxygen SBUs by cis- and trans-chdc(2-) ligands in a 2:1 ratio, 2 displays a complicated six-connected hex-type rod packing structure built by connection of rod-shaped neodymium-oxygen SBUs and trans-chdc(2-) ligands, and 3 features an unprecedented five-connected rod packing pattern constructed from rod-shaped samarium-oxygen SBUs and cis- and trans-chdc(2-) ligands in a 1:2 ratio.
Chemistry - An Asian Journal 04/2008; 3(3):542-7. · 4.50 Impact Factor
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ABSTRACT: Multilayer films composed of single-component and positively-charged tetraaminocalix[4]arenes are formed through hydrogen bonding.
Chemical Communications 06/2007; · 6.17 Impact Factor
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ABSTRACT: The hydrothermal reaction of 5-hydroxyisophthalic acid (H3L) and lead and nickel nitrates produced a heterometallic polymer [Pb6Ni(mu3-OH)8(La)2]n containing heptanuclear [Pb6Ni(mu3-OH)8]6+ units and a homometallic complex {[Pb(Lb)(H2O)].(H2O)0.25}n consisting of one-dimensional lead-oxide chains: evidently, the La and Lb ligands resulted from in situ hydroxyl-directed dinitration of L ligand during the hydrothermal reaction.
Chemical Communications 06/2006; · 6.17 Impact Factor
