A Series of Polyoxometalate-Viologen Photochromic Materials for UV Probing, Amine Detecting and Inkless and Erasable Printing.

In this work, by using two kinds of viologen ligands three POM-based Compounds were obtained under hydrothermal conditions, namely [Ag (bmypd) (β-Mo O ) ] (1) (bmypd ⋅ 2Cl=1,1'-[Biphenyl-4,4'-bis(methylene)]bis(4,4'-bipyridyinium)dichloride), [Ag (bypy) (HSiW O ) ] ⋅ 14H O (2) and [Ag (bypy)(γ-Mo O ) ] (3) (bypy⋅Cl=1-Benzyl-4,4'-bipyridyinium chloride). The structures were characterized by Fourier transform infrared spectroscopy (FT-IR), Powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS) and single crystal X-ray diffraction. Compounds 1-3 show excellent photochromic ability with fast photoresponse under the irradiation of ultraviolet light with different degrees of color changes.

Electrocatalytic and Hg Fluorescence Identifiable Bifunctional Sensors for a Series of Keggin Compounds.

By using a 2,2'-dimethyl-4,4'-bithiazole (dm4bt) ligand, Keggin polyanions, and different metal ions, nine Keggin-based compounds, namely, {[Ag(dm4bt)][Ag(dm4bt)]}(PWO)(HPWWO) (1), [Cu(dm4bt)][Cu(dm4bt)(PWO)] (2), [Cu(dm4bt)](SiWO) (3), {[Zn(dm4bt)](SiWO)} (4), [Zn(dm4bt)(HO)](HPMoMoO)·2HO (5), [Zn(dm4bt)(MoO)] (6), [Cd(dm4bt)][Cd(dm4bt)(HO)(PMoO)]·2HO (7), [Cd(dm4bt)](PMoO)·(Hdm4bt) (8), and [Cd(dm4bt)(HO)](HPMoMoO)·2HO (9), have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, IR spectroscopy, and elemental analyses. Compounds 1-9 are zero-dimensional structures except compound 6, which exhibits a one-dimensional structure. In compound 1, there are three isolated subunits: Keggin anions, binuclear [Ag(dm4bt)], and mononuclear [Ag(dm4bt)] clusters.

Systematic Investigation of Reaction-Time Dependence of Three Series of Copper-Lanthanide/Lanthanide Coordination Polymers: Syntheses, Structures, Photoluminescence, and Magnetism.

Three series of copper-lanthanide/lanthanide coordination polymers (CPs) Ln(III) Cu(II) Cu(I) (bct)3 (H2 O)2 [Ln=La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Er (10), Yb (11), and Lu (12), H2 bct=2,5-bis(carboxymethylmercapto)-1,3,4-thiadiazole acid], Ln(III) Cu(I) (bct)2 [Ln=Ce (2 a), Pr (3 a), Nd (4 a), Sm (5 a), Eu (6 a), Gd (7 a), Tb (8 a), Dy (9 a), Er (10 a), Yb (11 a), and Lu (12 a)], and Ln(III) 2 (bct)3 (H2 O)5 [Ln=La (1 b), Ce (2 b), Pr (3 b), Nd (4 b), Sm (5 b), Eu (6 b), Gd (7 b), Tb (8 b), and Dy (9 b)] have been successfully constructed under hydrothermal conditions by modulating the reaction time. Structural characterization has revealed that CPs 1-12 possess a unique one-dimensional (1D) strip-shaped structure containing two types of double-helical chains and a double-helical channel. CPs 2 a-12 a show a three-dimensional (3D) framework formed by Cu(I) linking two types of homochiral layers with double-helical channels.

Three multi-nuclear clusters and one infinite chain induced by a pendant 4-butyl-1H-pyrazole ligand for modification of Keggin anions.

By utilizing pendant 4-butyl-1H-pyrazole (Hbpz) with an alkyl "tail"--(CH2)3CH3, four Keggin-based complexes containing different transition metal multi-nuclear clusters and an infinite chain were hydrothermally synthesized and structurally characterized, [Cu(I)4(bpz)4(pz)2(H6PW11Cu(II)O39)2]·10H2O (1), [Cu(II)2(bpz)2(H2O)2(H3PCu0.5Mo11.5O40)]·3H2O (2), [Ag3(bpz)2(pz)(H4SiW12O40)]·4H2O (3) and [Ag5(bpz)4(H5/2PMo12O40)2]·6H2O (4) (pz = pyrazole).

Unprecedented application of flexible bis(pyridyl-tetrazole) ligands to construct helix/loop subunits to modify polyoxometalate anions.

By introducing the unprecedented and flexible isomeric bis(pyridyl-tetrazole) ligands into a polyoxometalates (POMs) system, three POM-based compounds, {Ag2(4-bptzb)2(H2O)2[H2PMo12O40]2}·4-bptzb·5H2O (1), [Ag4(3-bptzb)2(PMo(V)Mo(VI)11O40)]·2H2O (2), and Ag3(3-bptzb)2.5(H2O)2[H3P2W18O62] (3) [4-bptzb = 1,4-bis(5-(4-pyridyl)tetrazolyl)butane and 3-bptzb =1,4-bis(5-(3-pyridyl)tetrazolyl)butane], were synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction analyses. Compound 1 exhibits a dimeric structure constructed from two Keggin [PMo12O40](3-) anions and a binuclear [Ag2(trans-4-bptzb)2](2+) subunit in which the trans-4-bptzb acts as a bidentate bridging ligand with one tetrazolyl group.

The key role of -CH3 steric hindrance in bis(pyrazolyl) ligand on polyoxometalate-based compounds.

Through using two kinds of bis(pyrazolyl) ligands, four polyoxometalate (POM)-based compounds were hydrothermally synthesized and structurally characterized, [Ag3(Hbhpe)2(H2O)(H2PMo12O40)]·H2O (1), [Ag(H2bdpm)2(H2PW12O40)]·4H2O (2), [Ag6(H2bdpm)6(HPW(VI)8W(V)4O40)]·2H2O (2) and [Ag4(H2bdpm)4(H2P2W18O62)]·3H2O (4) (H2bhpe = 1,2-bis(1-H-pyrazolate)ethane, H2bdpm = 1,1'-bis(3,5-dimethyl-1H-pyrazolate)methane). In compound 1, the Ag-Hbhpe subunit is a 2D layer containing large penta-membered cycles and small tri-nuclear Ag(I) clusters. The Keggin anions covalently float on the large cycles.

Assembly and properties of transition-metal coordination polymers based on semi-rigid bis-pyridyl-bis-amide ligand: effect of polycarboxylates on the dimensionality.

Seven new coordination polymers, [Co(3-bpcd)(1,3-BDC)(H(2)O)(3)]·H(2)O (1), [Co(3-bpcd)(1,2-BDC)(H(2)O)]·H(2)O (2), [Co(3)(3-bpcd)(1,2,4-BTC)(2)(H(2)O)(4)]·4H(2)O (3), [Co(3-bpcd)(NPH)]·2H(2)O (4), [Cu(3-bpcd)(1,3-BDC)] (5), [Cu(3-bpcd)(1,2-BDC)] (6), [Cu(3-bpcd)(1,3,5-HBTC)(H(2)O)](2)·2H(2)O (7) (3-bpcd = N,N'-bis(pyridin-3-yl)cyclohexane-1,4-dicarboxamide, 1,3-H(2)BDC = 1,3-benzenedicarboxylic acid, 1,2-H(2)BDC = 1,2-benzenedicarboxylic acid, 1,2,4-H(3)BTC = 1,2,4-benzenetricarboxylic acid, H(2)NPH = 3-nitrophthalic acid and 1,3,5-H(3)BTC = 1,3,5-benzenetricarboxylic acid) have been hydrothermally synthesized by assembling transition-metal cobalt-copper salts with semi-rigid bis-pyridyl-bis-amide ligand 3-bpcd and different aromatic polycarboxylic acids. Complex 1 exhibits a one-dimensional (1D) sinusoidal-like chain, which is further assembled into a three-dimensional (3D) supramolecular framework through hydrogen-bonding interactions. Complex possesses a 3D framework with 4-connected 6(6) topology, which contains a two-dimensional (2D) distorted asymmetric hexagonal grid.

Assemblies of copper bis(triazole) coordination polymers using the same keggin polyoxometalate template.

Four inorganic-organic hybrid compounds, [Cu(I)(4)(bte)(4)(SiW(12)O(40))] (1), [Cu(II)(2)(bte)(4)(SiW(12)O(40))].4H(2)O (2) [bte = 1,2-bis(1,2,4-triazol-1-yl)ethane], [Cu(I)(4)(btb)(2)(SiW(12)O(40))].2H(2)O (3), and [Cu(II)(2)(btb)(4)(SiW(12)O(40))].

Assembly of the highest connectivity Wells-Dawson polyoxometalate coordination polymer: the use of organic ligand flexibility.

Through tuning the length of flexible bis(triazole) ligands and different metal ion coordination geometries, four Wells-Dawson polyoxoanion-based hybrid compounds, [Cu 6(btp) 3(P 2W 18O 62)].3H 2O ( 1) (btp = 1,3-bis(1,2,4-triazol-1-y1)propane), [Cu 6(btb) 3((P 2W 18O 62)].2H 2O ( 2), [Cu 3(btb) 6(P 2W 18O 62)].

Asymmetrical polar modification of a bivanadium-capped Keggin POM by multiple Cu-N coordination polymeric chains.

An unprecedented asymmetrically modified bivanadium-capped Keggin polyoxometalate (POM), {AsMo12O40(VO)[VO(H2O)]}.[Cu(4,4'-bipy)]5.H2O (1) (bipy = bipyridine), has been hydrothermally synthesized and structurally characterized by a routine technique.