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Diamine-containing UiO-66 (UiO-66-(NH2)2) was utilized as a support to load PdAu nanoparticles (NPs) through a double-solvent strategy for the catalytic application in the dehydrogenation of formic...

The hydro(solvo)thermal reactions of CuI with diverse bisimidazole molecules were investigated, affording five new copper(I) iodides [Cu4I4(L1)2] (L1=1,3-bis(2-methylimidazol-1-ylmethyl)benzene) 1, [CuI(L2)] (L2=4,4′-bis(imidazolyl)biphenyl) 2, [Cu4I4(L3)] (L3=1,3-bis(2-methylimidazol-1-yl)propane) 3, [Cu4I4(L4)2] (L4=1,4-bis(2-ethylimidazol-1-yl)butane) 4, and [Cu4I4(L5)] (L5=1,4-bis(1-imidazoly)benzene) 5. X-ray single-crystal diffraction analysis reveals that (i) in 1, a tetranuclear Cu-I cluster (stepped cubane) is observed, and the L1 molecule only acts as an ancillary ligand; (ii) in 2, the L2 molecules extend the castellated Cu-I chains into a 2-D layer network with a certain thickness; (iii) in 2-D single-layer network of 3, a 1-D Cu-I column is found, which can be viewed as a longitudinal packing of stepped Cu4I4 cubanes; (vi) in 4, the L4 molecules propagate the cubic Cu4I4 cubanes into a 3-D 4-fold interpenetrated network with a cds topology; and (v) in 5, the L5 molecules link the 1-D Cu-I ribbons into a 2-D single-layer network. The photoluminescence analysis indicates that 1, 2 and 4 emit light (red light for 1; yellow light for 2 and 4), while 3 and 5 are not emissive. Their photoluminescence behaviors are confirmed to be related to the Cu···Cu interactions in the molecules.

Three new organic–inorganic hybrid compounds based on [SiNb12V2O42]12− have been obtained under hydrothermal conditions and characterized by IR, XRD, and single crystal X-ray diffraction analysis. Single crystal X-ray analysis reveals that [Cu(en)2]4[Cu(en)2(H2O)2]2[SiNb12V2O42]·14H2O (1) is constructed from [SiNb12V2O42]12− and two kinds of copper complexes, polyoxoanions in [Cu(en)2]2[Cu(en)2(H2O)]4[SiNb12V2O42]·4H2O (2) and [Cu(en)2(H2O)2]4[Cu(en)2(H2O)]2[SiNb12V2O42]·11H2O (3) are identical to compound 1, but the copper complex combinations of these two compounds are different from that of compound 1. Therefore, the final structures of the three are different from one another. All the three compounds are excellent catalysts for the epoxidation of styrene. In addition, we also synthesized an isopolyniobate K6H2Nb6O19·17H2O (4), which exhibits a 3-D structure constructed from [Nb6O19]8− and potassium clusters.

Five new organic–inorganic hybrid compounds based on [P2W18O62]6− (abbreviated as {P2W18}) and several types of transition metal complexes (TMCs) have been synthesized and characterized by IR, UV-Vis, XRD, cyclic voltammetry measurements and single crystal X-ray diffraction analysis. [Cu(phen)2][Cu(phen)(H2O)3][Cu(phen)2(H2O)][P2W18O62]·8H2O (1) (phen = 1,10-phenanthroline) is a {P2W18} bi-supported complex of phen, while [Cu(2,2′-bpy)(H2O)2]2[Cu(2,2′-bpy)2][P2W18O62]·3.5H2O (2) (2,2′-bpy = 2,2′-bipyridine) is a 1-D chain structure formed by {P2W18} and copper complexes of 2,2′-bpy. [Ag(2,2′-bpy)2]5[HP2W18O62]·H2O (3), [Ag(2,2′-bpy)(H2O)]2[Ag(2,2′-bpy)]2[Ag2(2,2′-bpy)3][P2W18O62] (4), and [Ag(2,2′-bpy)(H2O)]3[Ag2(2,2′-bpy)3][Ag(2,2′-bpy)][P2W18O62]·H2O (5) are constructed from {P2W18} and silver complexes of 2,2′-bpy. Compounds 4 and 5 are novel dimers of {P2W18} joined by silver complexes, while compound 3 contains two different kinds of silver complexes, forming a novel supramolecular structure. Each of the five compounds is formed by {P2W18} and more than one type of TMC. The formation mechanism of these compounds has been carefully discussed. In addition, we also synthesized two supramolecular structures based on {P2W18} and organic moieties: [H6P2W18O62](phen)5.5 (6) and [H6P2W18O62](phen)3·43H2O (7). The catalytic properties of these compounds were also tested.

A novel two-dimensional (2-D) solid material [Ni(en)2]2{SiMoVI8VIV6O42[Ni(en)2]2}·4H2O 1 (en = ethylenediamine) has been hydrothermally synthesized and structurally characterized by IR, UV–Vis spectrum, elemental analysis, XRD, ESR, XPS, X-ray diffraction analysis, magnetic property analysis and electrochemistry study. Single-crystal X-ray analysis reveals that the 2-D framework of compound 1 is based on Mo/V/Si bicapped Keggin clusters interconnected by nickel ethylenediamine complexes. Magnetic susceptibility measurement indicates that compound 1 exhibits antiferromagnetic coupling interactions.

Three new compounds based on arsenic–vanadium clusters {[Cu(im)2]4[H2As8V14O42(SO4)]}·H2O (1) and [Cu(phen)(im)]3[Cu(phen)2][As8V14O42(H2O)] (2, 3) (im = imidazole, phen = phenanthroline) have been synthesized and characterized by IR, UV–Vis, XRD, TG analysis, elemental analysis, single-crystal X-ray diffraction analysis and catalytic properties. Crystal analysis reveals that compound 1 shows an unprecedented 3-D twofold interpenetrating network structure with each of the two interpenetrating frameworks exhibiting a novel diamondoid framework structure based on POMs and transition metal complexes. Compounds 2 and 3 are based on identical polyanions and identical transition metal complexes. However, the two compounds are not isomorphous and isostructural with each other. That is to say, the two compounds have an identical chemical formula with different structures: the two are polymorphs of each other. In addition, catalytic properties of compounds 1–3 have been studied.

Seven novel compounds based on arsenic–vanadium clusters [Ni(im)(2,2′-bpy)]2[Ni(im)2]2[Ni(2,2′-bpy)][As8V14O42(H2O)] (1), [Ni(2,2′-bpy)3][Ni(im)2]0.5[Ni(2,2′-bpy)(im)][As8V14O42(H2O)] (1a), [Ni(2,2′-bpy)(phen)][Ni(2,2′-bpy)2][As8V14O42(H2O)]·H2O (2) and [Ni(2,2′-biim)(2,2′-bpy)2]2[As8V14O42(H2O)]·6H2O (3), [Cd(2,2′-bpy)(phen)2]2[As8V14O42(H2O)]·4H2O (4), [Cd4(phen)4(ox)(H2O)6][As6V15O42(H2O)]·2H2O (5) and [Co2(phen)4(ox)][H2As8V14O42(H2O)]·(apy)2·2H2O (6) (Him = imidazole, phen = 1,10-phenanthroline, 2,2′-biim = 2,2′-biimidazole, apy = 2-aminopyridine) have been synthesized and characterized by IR, UV-vis, XRD, TG, CD spectrum, elemental analysis and single-crystal X-ray diffraction analysis. Crystal analysis reveals that compound 1 is the first example of a hybrid compound constructed from polyoxometalates and transition metal mixed-organic-ligand complexes of negatively charged nitrogen-containing ligands and neutral nitrogen-containing ligands. Compound 1a is the first example of a POM supported TMC which is formed via arsenic–metal contact. Compound 2 is a chiral compound which exhibits a novel 1-D triple-chain structure constructed from [As8V14O42(H2O)]4− clusters, a type of chiral transition metal mixed-organic-ligand complex and a type of chiral transition metal complex. Compounds 3 and 4 are supramolecular compounds which are formed by [As8V14O42(H2O)]4− clusters and transition metal mixed-organic-ligand complexes, respectively. Compounds 5 and 6 are constructed from arsenic–vanadium clusters and transition metal complexes of nitrogen-containing ligands and oxalic groups. The catalytic properties of compounds 1 and 2–6 have been investigated and we found that the transition metal mixed-organic-ligand complexes have dramatic influences on the catalytic properties of catalysts.

Under hydro(solvo)thermal conditions, four organic bidentate bridging N,N′-donor ligands 1,3-bis(2-methylimidazol-1-yl)propane (L1), 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl (L2), 1,2-bis(2-methyl-1H-imidazol-1-ylmethyl)benzene (L3) and 5,6,7,8-tetrahydroquinoxaline (L4) were employed to react with CuBr/CuI, generating four 2-D layered copper(I)–polymer coordination polymer materials [Cu2Br2(L1)] 1, [CuI(L2)] 2, [CuI(L3)] 3 and [CuI(L4)0.5] 4. In 1–4, different Cu–X motifs are found: a cubic Cu4Br4 core in 1; a castellated Cu–I single chain in 2; a rhombic Cu2I2 core in 3; and a staircase-like Cu–I double chain in 4. The 2-D layer networks of 1–3 can all be simplified into a simple 44 topology (planar for 1 and 3; wave-like for 2), while the 2-D layer network of 4 has a 63 topology. The photoluminescence behaviors of 1–4 under a UV lamp suggest that 1 and 2 possess fluorescence thermochromism properties. Under the UV lamp, with the decrease in temperature, (i) 1 exhibits a yellow-to-red emission; (ii) 2 exhibits a yellow-to-green emission; (iii) 3 always emits green light; and (iv) 4 never emits light. These are further confirmed by their emission spectra. From 297 K to 77 K, the emission of 1 exhibits a large red shift from 561 nm to 623 nm; the emission of 2 exhibits a large blue shift from 571 nm to 515 nm; only a minor red shift is observed for the emission of 3; and no peaks appear in the emission spectra of 4. The crystal data of 1 and 2 at different temperatures have been collected for revealing the origination of their fluorescence thermochromism properties. Based on the above investigations, the effect of the rigidity/flexibility of the organic ligand on the fluorescence thermochromism properties of copper(I)–polymer coordination polymer materials is discussed. The quantum yields at 297 K and the photoluminescence lifetimes at 297 K and 77 K for 1–3 were also measured for better understanding their photoluminescence properties.

Having been designed via bottom-up strategy based on density functional theory(DFT) calculations, a complex of ytterbium(II) with pyridyl amido ligand was successfully synthesized by one-pot reaction in laboratory. DFT calculation shows that pyridyl amido ligands can stabilize the complex via steric and electron effect. This success in integrating computation with synthesis will inspire more explorations in the development of a new complex in lanthanide chemistry.

A new compound based on bi-capped Keggin polyoxoniobates and copper coordination complexes, with formula [Cu(en)2][Cu(en)2(H2O)2][Cu(en)2(H2O)]2[H4SiNb12V2O42]·7H2O (1) (en = ethylenediamine), was obtained under hydrothermal condition and characterized by single crystal X-ray diffraction, infrared spectrum (IR), powder X-ray diffraction (PXRD), Ultraviolet–visible spectroscopy (UV–vis) and electron spin resonance (ESR) analysis. Compound 1 has three different types of copper complexes in it. A [Cu(en)2]2 + and two [Cu(en)2(H2O)]2 + fragments were supported by the polyoxoniobate to form a novel polyoxoniobate tri-supported coordination complex.

A new compound, [Cu(en)2(H2O)]{[Cu0.5(en)]3[VVW6.5VIW3VV4.5IVO42Cu(en)2]}·3.5H2O (1) (en = ethylenediamine), has been hydrothermally synthesized and characterized by elemental analysis, IR, ESR, XPS, TG analysis and single-crystal X-ray diffraction analysis. Compound 1 exhibits a novel 2-D structure linked by 1-D infinite left- and right-handed helical chains and transition metal coordination fragments. Adjacent layers are further interconnected into a 3-D supramolecular structure via hydrogen bonds. The magnetic susceptibility of compound 1 demonstrated the presence of antiferromagnetic interactions.

A new compound, [Cu(en) 2 ][Cu(en) 2 (H 2 O)] 2 [SiMo 8 V 6 O 42 ][Cu(en) 2 ]·1.5H 2 O ( 1 ) (en = ethylenediamine), has been hydrothermally synthesized and characterized by elemental analysis, IR, ESR spectrum, TG analysis and single-crystal X-ray diffraction analysis. Compound 1 represents a 1-D zigzag chain-like structure constructed from dimeric units of bi-capped polyoxoanions {[Cu(en) 2 ] 2 [Cu(en) 2 (H 2 O)] 2 [SiMo 8 V 6 O 42 ] 2 [Cu(en) 2 ]} 6− and transition metal coordination fragment [Cu(en) 2 ] 2 + . The adjacent chains are further interconnected into a 3-D supramolecular structure via hydrogen bonds. The magnetic susceptibility of 1 demonstrated the presence of antiferromagnetic interactions.

Two new compounds [Cu(enMe) 2 ][Cu(enMe) 2 (H 2 O)][SiMo V 6 Mo VI 6 Sb 2 O 40 ] ( 1 ) and [Ni(en) 2 ] 2 [SiMo V 6 Mo VI 6 Sb 2 O 40 ] ( 2 ) (enMe = 1,2-diaminopropane, en = 1,2-ethylenediamine) have been hydrothermally synthesized and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses and single crystal X-ray diffraction. The two compounds represent the first examples of hybrids based on bi-antimony capped Keggin polyanions {SiMo 12 Sb 2 O 40 } and different transition metal coordination complexes.

[Cu(en)2][Cu(en)2(H2O)2] [Cu(en)2(H2O)]2 [H4SiNb12V2O42]·7 H2O (I) based on bi-capped Keggin-type polyoxoniobates and Cu coordination complexes is prepared hydrothermally.

Four new organic–inorganic hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}: [H24,4′-bpy][PMo12Sb2O40]·6H2O (1), [Him]2[PMo12Sb2O40]·H2O (2), [H3(DABCO)2][PMo12Sb2O40]·2H2O (3) and [Mn(phen)3][PMo12Sb2O40] (4) (bpy = bipyridine, im = imidazole, DABCO = 1,4-diazabicyclo[2,2,2]octane, phen = phenanthroline) have been prepared hydrothermally and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses, fluorescence analysis and single crystal X-ray diffraction analyses. The four compounds are new examples of hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}. Compound 1, 2 and 3 are constructed from {PMo12Sb2O40} anions and different organic moieties, respectively. Compound 4 is formed by combining {PMo12Sb2O40} anions and manganese coordination complexes.

At the ambient condition, the simple self-assembly between ZnI2, KI, and dabco in acidic H2O/C2H5OH solution produced a tetranuclear iodine cluster with diprotonated dabco as the cation [H2dabco](I4) (dabco = 1,4-diazabicyclo[2,2,2]octane) 1. But the same precursors reacted under the solvothermal condition, producing a chained iodine cluster polymer with dedabco2+ as the cation [dedabco](I3)2 (dedabco2+ = N,N′-diethyl-1,4-diazabicyclo[2,2,2]octane) 2. Note that dedabco2+ originated from the solvothermal in situ N-alkylation of dabco with C2H5OH solvent in acidic KI solution.

Five new hybrid compounds constructed from polyoxometalates and transition metal coordination complexes with lower positive charge: [PW11CuO39][Cu(bpy)2]5 (1), [BW12O40][Cu(bpy)2]5 (2) [BW12O40][Cu(Phen)2]3[Cu(Phen)(H2O)]2·2H2O (3), [SiW12O40][Cu(bpy)2]4 (4) and [PW12O40][Cu(bpy)2]4 (5) have been prepared and characterized by IR, UV-Vis, XPS, XRD and single crystal X-ray diffraction analyses. The packing motif of the [Cu(bpy)2]+ copper coordination complexes in compound 1 exhibits square supramolecular channels running along the a axis, which are then filled by the [PW11CuO39]5− ions. Compound 2 is isomorphours with compound 1. Compound 3 contains a novel 2-D supramolecular layer structure constructed from [Cu(Phen)2]+ copper coordination complexes through π⋯π interactions. The packing motif of the [Cu(bpy)2]+ copper coordination complexes in compound 4 exhibits a supramolecular channel which is different from compound 1. Compound 5 is isomorphours with compound 4.

Four new heteropolyanions {[PMo12Sb2O40][Cu(Im)2]2}·Im (1), {[PMo12Sb2O40][(Cd(Phen)2)2Cl]} (2), [Cu(Phen)2]2[PMo12Sb2O40] (3) and [Cd(bpy)4(H2O)2][PMo12Sb2O40]·bpy·2H2O (4) (Im = imidazole, Phen = 1,10-phenanthroline, bpy = 4,4′-bipyridine) have been synthesized and characterized by IR, UV/Vis spectrophotometry, X-ray photoelectron spectroscopy, powder XRD analyses and elemental analyses. Single-crystal X-ray diffraction analyses revealed that these four compounds represent examples of compounds based on the bis-antimony-capped Keggin polyoxoanion {PMo12Sb2O40} and different transition-metal coordination complexes. Compound 1 exhibits a novel 1D chain structure, compound 2 is the first example of an extended structure constructed from polyoxoanions, transition-metal coordination complexes and halide ions and compounds 3 and 4 are supramolecular structures constructed from {PMo12Sb2O40} polyoxoanions and different transition-metal coordination fragments.

The hydrothermal reactions of Cul, KI and bidentate amines [1, 10-phenanthroline (phen) or ethylenediamine (en)] gave the three copper (I) halide compounds, Cu3I3 (phen)2 (1), CuI (phen)2 (2) and [Cu (en)2] [CuI2]2 (3), which were structurally characterized via single-crystal X-ray diffraction studies. Hydrogen bonds and τ-τ interactions are the most remarkable structural features of the title compounds. All can be described as higher-dimensional supramolecular compounds connected via these secondary bondings. Moreover, the title compounds were characterized by elemental analyses, IR spectra and TGA analyses. The third-order non-linear optical properties of the title compounds were also investigated and all exhibit nicer non-linear absorption and self-focusing performance.

The title compound Cu2Cl2phen (phen = 1,10-phenanthroline, C12H8N2) 1 was synthesized from CuCl2·2H2O, CuCl and phen by hydrothermal method and its structure was determined by single crystal X-ray analysis. With phen, CuG forms one-dimensional chains, which comprise two zigzag chains based on fused Cu-X units and connected via covalent bonds. The compound contains two crystallographically unique monovalent copper ions, Cu(1) and Cu(2). The Cu(1) atom in the tetrahedral site, is coordinated to two bridging Cl− and two N atoms in phen. The Cu(2) atom with a slightly distorted triangular planar geometry, is coordinated to three Cl−. The compound 1 was crystallized in monoclinic, space group P21/n with a = 0.37338(4), b = 1.9510(2), c = 1.68008(19) nm, β = 95.605 (3)°, R = 0.0458, and was characterized by elemental analysis, IR spectrum and TGA analysis.

A polyoxometalate [Co(phen)3][Co(en)3][Co(en)2(H2O)2][Co(en)2]0.5[ O40(VIVO)2] · 6H2O (1) (en = ethylenediamine, phen = 1,10-phenanthroline) has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, electron paramagnetic resonance, X-ray photoelectron spectroscopy, elemental analyses, and thermogravimetry. The structure is an interesting 3-D supramolecular network containing bi-capped Keggin-type molybdenum–vanadium clusters with transition metal complexes generated in situ under mild hydrothermal conditions. Compound 1 contains four different counteractions being coordinated complexes of cobalt. The magnetic properties of 1 have also been studied in the temperature range of 4–300 K, and its magnetic susceptibility obeys the Curie–Weiss law, showing ferromagnetic coupling.

Four inorganic–organic hybrid materials based on poly(oxomolybdophosphate) cluster building blocks have been obtained by hydrothermal methods. 1 shows a 2-D sheet structure, 2 and 3 possess 1-D chain structures and 4 is the discrete cluster. Crystal structural analysis reveals that the dimensionality and organization of those compounds can be tuned by the pH value of the reaction system. In addition, the fluorescence emissions are analysed of compounds 1, 2 and 4 containing Cd atoms with d10 electronic configuration red-shift along with the increase in the dimensions of those compounds.

A novel modified POM [ H 4 PMo 7 V Mo 5 VI O 40 Sb 2 III ] (im)2·2H2O (im = imidazole) (1) has been hydrothermally synthesized from the system Sb2O3–H3PMo12O40–H2C2O4–im and characterized by elemental analysis, IR, UV–Vis, XPS, TGA and single crystal X-ray diffraction. The highly reduced polyoxoanion [ PMo 7 V Mo 5 VI O 40 Sb 2 III ] 4 - represents the first example of bi-antimony capped α-Keggin phosphomolybdate, in which the Sb atoms exhibit novel Ψ-rhombic pyramidal {SbO4E} hemidirected coordination geometry with coordination number 4.

Two new supramolecular compounds based on tungsten–vanadium polyoxoanions formulated as [Cu(2,2′-bipy) 3 ] 2 H 14 [PW 2.2 V 9.8 O 40 (VO) 2 [Cu(2,2′-bipy) 2 H 2 O] 2 ][PW 2.2 V 9.8 O 40 (VO) 2 ]·10H 2 O ( 1 ) and [Cu 4 (2,2′-bipy) 4 (H 2 O) 2 (PO 4 ) 2 ]H 6.5 [PW 8.4 V 3.6 O 40 ]·2H 2 O ( 2 ) (2,2′-bipy=2,2′-bipyridine) have been synthesized hydrothermally and characterized by IR, TG, XPS and X-ray diffraction analyses. Crystal structure analyses reveal that compounds 1 and 2 exhibit novel 2D supramolecular layer structures constructed from tungsten–vanadium polyoxoanions and different types of secondary building units (SBUs), respectively, the different SBUs are formed by [Cu(2,2′-bipy) 2 H 2 O] 2+ and [Cu(2,2′-bipy) 3 ] 2+ cations in compound 1 and [Cu 4 (2,2′-bipy) 4 (H 2 O) 2 (PO 4 ) 2 ] 2+ cations in 2 , respectively. Study of magnetic properties indicated the presence of antiferromagnetic behaviors for both compound 1 and 2 .

Two new polyoxometalates [ Ni ( phen ) 3 ] [ Ni ( en ) 3 ] [ Ni ( en ) 2 ( H 2 O ) 2 ] [ Ni ( en ) 2 ] 0.5 [ PW VI 7 W V 2 V IV 3 O 40 ( V IV O ) 2 ] · 6 H 2 O (1) and [ Ni ( phen ) 3 ] 2 [ Ni ( en ) 2 ] Na [ PW VI 7 W V 2 V IV 3 O 40 ( V IV O ) 2 ] · 8 H 2 O (2) (en=ethylenediamine, phen=1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, EPR, XPS, elemental analysis and thermogravimetry. Their structures exhibit interesting 3D supramolecular networks, and contain new bicapped (pseudo-) Keggin-type tungsten–vanadium cluster and the template transition-metal complexes (TMCs) being generated in situ under mild hydrothermal conditions. Interestingly, compound 1 contains four different kinds of nickel complex countercations.

Two new molybdenum–vanadium polyoxometalate tri-supported transition metal complexes [Cu(2,2 ′ -bipy)] [Cu(2,2 ′ -bipy) 2 ] 2 [PMo 8 V 6 O 42 ]· n H 2 O ( n = 1.5 ( 1 ) and n = 2 ( 2 ); 2,2 ′ -bipy = 2,2 ′ -bipyridine) have been hydrothermally synthesized and characterized by elemental analyses, IR, XPS and single-crystal X-ray diffraction analyses. Both compound 1 and compound 2 contain molybdenum–vanadium polyoxometalates, each of which support one [Cu(2,2 ′ -bipy)] 2+ cation and two [Cu(2,2 ′ -bipy) 2 ] 2+ cations, respectively. The difference between compound 1 and compound 2 is that the polyoxoanion of 1 is a bi-capped α-Keggin cluster and that of 2 is a bi-capped pseudo-Keggin one. Studies of magnetic properties indicated the presence of ferromagnetic behaviors for compounds 1 and 2 .

A novel polyoxometalate {[Ni(enMe) 2 ] 2 [Ni(enMe) 2 (H 2 O)] 2 [As 2 W 18 Ni 4 (enMe) 2 O 68 ]}·2H 3 O·2H 2 O ( 1 ) (enMe = 1,2-propylenediamine) has been synthesized and characterized, which is the first high-dimensional structure constructed from sandwich-type transition metal substituted tungstates and transition metal coordination groups.

A novel polyoxometalate [Cu(en)2(H2O)]2[Cu(en)2]2 [AsW9V7O44] · 2H2O (1) has been hydrothermally synthesized and characterized by elemental analysis, IR spectrum, XPS spectrum and single crystal X-ray diffraction analysis. It is the first example of two-dimensional layer structure constructed from four vanadium-capped pseudo-Keggin tungstates. The study of the magnetic susceptibility of 1 demonstrates the presence of ferromagnetic interactions.

Two novel coordination polymers, {[Cu(ip)(Him)2(DMF)]·H2O} (1) and Co(ip)(Him)2 (2), (ip = isophthalate, Him = imidazole) were prepared under hydrothermal conditions and their structures were determined by single-crystal X-ray diffraction. X-ray structural analysis reveals that 1-D zigzag metal-organic chains are connected to form a 3-D supramolecular framework in compounds 1 and 2 by hydrogen-bonding and π–π interaction or other intermolecular contacts. Infrared, UV–vis, and elemental analysis were performed to characterize the two compounds. The result of magnetic determination for compound 2 shows there exist antiferromagnetic interaction between magnetic centers.

Six new complexes constructed by 5-sulfosalicylic acid and bipyridyl-like ligands (2,2′-bipy and 1,10-phen), namely [Cu4(OH)2(ssal)2(phen)4 · 7H2O] (1), [Cu4(OH)2(ssal)2(bipy)4 · 2H2O] (2), [Cd(Hssal)(bipy)] (3), [Cd(HL)2(phen)2] (4), [Cr(ssal)(bipy)(H2O)2 · 2H2O] (5) and [Cr(ssal)(phen)2] (6) (H3ssal = 5-sulfosalicylic acid, H2L = p-hydroxybenzenesulfonic acid, bipy = 2,2′-bipy, phen = 1,10-phen) were prepared under hydrothermal conditions and their structures were determined by single-crystal X-ray diffraction. Complexes 1 and 2 are both tetranuclear copper complexes with a stepped topology. In complex 3, a new coordination mode of the Hssal2− group is reported in this work. During the synthetic process of complex 4, in situ decarboxylation of 5-sulfosalicylic acid into p-hydroxybenzenesulfonic acid is involved. Two chromium 5-sulfosalicylates (5 and 6) are reported for the first time. These new complexes display different supramolecular structures by O–H⋯O, C–H⋯O hydrogen bonds as well as π⋯π, C–H⋯π and O⋯π interactions. The results of magnetic determination show that ferromagnetic interactions exist in complex 1, however, antiferromagnetic interactions exist in 2.

A cobalt(II) thiocyanate complex [Co(py)4(NCS)2] 1 (py = pyridine) has been synthesized by low-temperature solid-state reaction. Single crystal X-ray analysis reveals that 1 possesses a one-dimensional (1-D) zigzag chain structure. Each Co ion is symmetrically coordinated by four pyridine ligands and also coordinates with two NCS− anions. Compound 1 was characterized by elemental analyses, IR spectra and UV-visible spectra. The third-order non-linear optical (NLO) properties were also investigated and they exhibit non-linear absorption and self-defocusing performance with modulus of the hyperpolarizability 9.46 × 10−30 esu for 1 in a 3.6 × 10−4 mol dm−3 DMF solution.

The reactions of (NH4)(2)WS4 and three polycarboxylate ligands {including nitrilotriacetate (nta(3-)), citrate (Hcit(3-)) and ethylenediaminetetra acetate (EDTA(4-))} in H2O/EtOH at ambient temperature have resulted in three new trioxotungsten (VI) complexes, K-3[WO3(nta)]center dot H2O 1, (NH4)(4)[WO3(cit)]center dot 2 H2O 2 and K-2(NH4)(2)[W2O6(EDTA)]center dot 4H(2)O 3, respectively. These three complexes have been characterized by IR, XPS, TGA-DTA, H-1 and C-13 NMR spectroscopy. And their structures have been determined by X-ray crystallographic studies, which confirm that I and 2 are mononuclear compounds and 3 is a binuclear compound. Each tungsten atom in 1-3 is coordinated to three unshared oxygen atoms, which adopt fac stereochemistry, while the remaining fac positions are occupied by three atoms from the ligands. The electrochemical properties of 2 and 3 have been investigated. (c) 2006 Elsevier B.V. All rights reserved.

The title layered double salt Mn3(OH)2(SO4)2(H2O)2 · K2SO4 (1) was obtained from a simple hydrothermal reaction of CdSO4 · 8/3H2O, MnCl2 · 4H2O, α-aminopyridine (apy) and KI. X-ray analysis reveals that the two-dimensional (2-D) sheet of 1 is built up of the dimers of edge-sharing Mn(1) octahedral, extended by the apices of Mn(2) octahedral together with μ3 and μ4 SO4 groups. With free K+ ion as guest species, the 2-D sheets are further self-assembled into a 3-D supramolecular network with 1-D channels through the Ow-H ⋯ O hydrogen-bonded interactions. The magnetic property of 1 was investigated, and a classical behavior is observed with an antiferromagnetic order below 12.5 K.

Mo2O2S2(HGly)(GlY)(2) 1 and K-6[Mo2O2S2(nta)(2)][Mo2O2S2(ntaH)(2)]center dot 4H(2)O 2 were synthesized by the reactions of (NH4)(2)MoS4 and amino acids L (L = glycine, nitrilotriacetic acid) in ethanol-water medium at ambient temperature. The two complexes were characterized by elemental analysis, infrared spectra, UV-visible spectra, TG-DTA and XPS.

A novel molybdenum–copper cluster with highly delocalized mixed-valence Cu(I)/Cu(II) [MoO3Cu2(obipy)2]2O (1), has been hydrothermally synthesized and characterized by the elemental analyses, IR, XPS, TG analysis and the single crystal X-ray diffraction. The feature of 1 is that two copper atoms have different coordination configuration and valences. Variable temperature magnetic susceptibility measurements show the occurrence of a weak ferromagnetic interaction in 1.

A novel polyoxometalate ( C 2 N 2 H 9 ) 2 [ PMo 5 V Mo 7 VI Sb 2 III O 40 ] · 2 H 2 O (1) has been synthesized in the system of Sb2O3-(NH4)6Mo7O24 · 4H2O-H3PO4-en-H2O under hydrothermal conditions and characterized by IR, TGA, elemental analyses, single crystal X-ray diffraction and XPS. Interestingly, compound 1 displays three-dimensional network consisting of one-dimensional sinusoidal chain [(Hen)2(H2O)2]2+ and two-dimensional layer formed by [ PMo 5 V Mo 7 VI Sb 2 III O 40 ] 2 - . The structure unit [ PMo 5 V Mo 7 VI Sb 2 III O 40 ] 2 - is the first example of bicapped by antimony α-Keggin structure.

Three novel heteropolyoxovanadates, [Ni(2,2'-bpy) 3 ] 2 [{Ni-(en) 2 }As 6 V 1 5 O 4 2 (H 2 O)].9.5H 2 O (1), [Zn 2 (dien) 3 (H 2 O) 2 ] 1 / 2 -{[Zn 2 (dien) 3 ]As 6 V 1 5 O 4 2 (H 2 O)}.2H 2 O (2), and [Co(enMe) 2 ] 3 -[As 6 V 1 5 O 4 2 (H 2 O)]2H 2 O (3), were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Crystal data: 1, monoclinic, P2 1 /n, a = 14.0324(9) A, b = 13.9900(8) A, c = 30.5785(19) A, β = 102.861(1)°, Z = 2; 2, monoclinic, P2 1 /c, a = 13.361(5) A, b = 23.979(8) A, c = 22.873(8) A, β = 102.459(4)°, Z = 4; 3, triclinic, P1, a = 13.2976(1) A, b = 15.0583(1) A, c = 20.1661(2) A, a = 85.620(8)°, β = 79.553(9)°, y = 65.087(9)°, Z = 2. Compound 1 consists of 1D [(Ni(en) 2 }As 6 V 1 5 O 4 2 (H 2 O)] 4 - chains and [Ni(2,2'-bpy) 3 ] 2 + cations, in which the chain host has a molecular recognition ability for the chiral guest cations. Compound 2 is constructed from linking of the [As 6 V 1 5 O 4 2 ] 6 - polyoxoanions and novel dinuclear [Zn 2 (dien) 3 ] 4 + cations into the first 1D helical As-V-O cluster chain. Compound 3 is the first 2D framework based on [As 6 V 1 5 O 4 2 ] 6 - polyoxoanions as building blocks.

The new polyoxometalate double-supporting transition metal complexes, {[Co(phen)2]2C2O4} {H2P O44[Co(phen)2H2O]2}·7H2O (1) (phen = 1,10-phenanthroline) have been hydrothermally synthesized and characterized by single crystal X-ray analysis, IR, XPS, ESR and elemental analysis. Compound 1 is composed of a highly reduced tetra-capped pseudo-Keggin polyoxoanion supporting two transition metal complexes, a binuclear cobalt complex cation and lattice water. The magnetism and third-order non-linear optical properties of 1 have also been studied.

A group of four binuclear sulfur-bridged molybdenum–polycarboxylato complexes with homocitrate, citrate, cysteine, ethylenediaminetetraacetate ligands, respectively, have been synthesized and characterized. These complexes were prepared in order to study the interaction of Mo and homocitrate in the FeMo-co of nitrogenases. In the structures of K 4 (NH 4 ) 2 [Mo 2 O 2 S 2 (C 6 H 4 O 7 ) 2 ] · 10H 2 O ( 2 ), (NH 4 ) 2 [Mo 2 O 2 S 2 (C 3 H 5 SNO 2 ) 2 ] · 5H 2 O ( 3) and (NH 4 ) 2 [Mo 2 O 2 S 2 (C 10 H 12 N 2 O 8 )] · 3.5H 2 O ( 4 ), molybdenum (V) atom adopts a distorted octahedral arrangement through a terminal oxygen atom, two bridging sulfur atoms and three atoms from the ligand (hydroxyl, α-, β-carboxylates, sulfide or amine). The coordination mode of homocitrate ligand in K 5 (NH 4 )[Mo 2 O 2 S 2 (C 7 H 5 O 7 ) 2 ] · 3H 2 O · CH 3 OH ( 1 ) has been proposed in a tridentate fashion via its hydroxyl and a pair of carboxylate groups (α-, β-carboxylates). The electrochemical properties of these complexes have been discussed.

Two new arsenic–vanadium clusters, [Co(2,2′- bpy)3]2[As8V14O42(H2O)] · 3H2O (1), [2,2′-bpy][Ni(2,2′-bpy)3]2[As8V14O42(H2O)] · 3H2O (2) (2,2′-bpy=2,2′-bipyridine), have been hydrothermally synthesized and characterized by IR, elemental analysis, UV–VIS, EPR, TGA, XPS, and single crystal X-ray diffraction analysis. Crystal data: 1, triclinic, P1, a=14.368(3) A, b=16.753(3) A, c=24.632(5) A, α=94.15(3)°, β=93.16(3)°, γ=113.05(3)°, Z=2; 2, monoclinic, P21/c, a= 30.2150(4) A, b=14.0690(3) A, c=26.0536(3) A, β=106.8960(10)°, Z=4. X-ray crystallographic studies showed that crystals 1 and 2 are both composed of discrete cluster anion [As8V14O42(H2O)]4− and transition metal coordination complexes [M(2,2′-bpy)3]2+ (M=Co or Ni). Interestingly, compound 2 contains another neutral organic space filler of 2,2′-bpy. To the best of our knowledge, compounds 1 and 2 are the first examples of structurally characterized vanadium/2,2′-bpy/arsenate polyoxometallates.

The coordination polymer {K[Mn(C6H5O7)(H2O)]}n (1) (C6H5O73− = citrate trianion) was synthesized by solvothermal reaction and characterized analytically, spectroscopically (IR, EPR, XPS), thermally and magnetically. In compound 1, each citrate served as the unique pentadentate ligand coordinating to three Mn(II) ions. The carboxylate-bridged di-manganese cores were interlocked by α- and β-carboxylates of the citrate chains into 2D layers, which are then woven in [1 0 0] direction into a novel 3D network by the K+ linkers.

Four zinc(II) or cadmium(II) supramolecular compounds, namely, [Zn(ox)(Him)]n (1), [Zn(bta)2]n (2), [Zn(H2O)4(na)2]n (3), and [Cd2(ox)(OH)2]n (4) (ox = oxalate anion, Him = imidazole, bta = benzotriazole anion, and na = nicotinic anion), have been synthesized. Among them, 1 is constructed to be a 3-D supramolecular framework by covalent and noncovalent interactions, 2 containing two bta coordination modes displays a 2-D layer structure linked by covalent bonds, the 3-D network of 3 is mainly constructed by strong hydrogen bonds, while 4 exhibits a 3-D framework with 1-D channels only constructed by covalent interactions. The different metal centers and ligand dimensions result in the different structures although they were obtained from similar reaction systems. All of these compounds display strong fluorescence emissions in the blue region, which may be assigned to charge transfer between metal and ligand (for 1, 3, and 4) and the π → π* transition of bta (for 2).

The novel polyoxometalate ([As(8)V(13)NiClO(41)][Ni(en)(2)(H(2)O)][Ni(en)(2)])([Ni(en)(2)(H(2)O)(2)](0.5)).4H(2)O (1), which is the first example of a chainlike inorganic-organic hybrid polymer based on dimeric polyoxoanions linked by nickel complex fragments, has been synthesized in the system of As(2)O(3)-V(2)O(5)-H(2)C(2)O(4)-en-NiCl(2).6H(2)O-H(2)O under hydrothermal conditions and characterized by IR, TGA, elemental analysis, single crystal X-ray diffraction, XPS, and magnetic susceptibility studies, respectively. This compound crystallized in the triclinic space group P with a = 13.358(3) angstroms, b = 14.198(3) angstroms, c = 19.723(4) angstroms, alpha = 83.88(3) degrees, beta = 86.04(3) degrees, gamma = 64.66(3) degrees, V = 3360.2(2) angstroms(3), and Z = 2. Interestingly, the dimeric polyoxoanion contains two ([Ni(en)(2)(H(2)O)][As(8)V(13)NiClO(41)]) cluster units linked by Ni-O-As bonds and is a Ni-substituted [As(8)V(13)NiClO(41)] cluster supported by [Ni(en)(2)(H(2)O)] coordination fragment. The chainlike structure consists of ([Ni(en)(2)(H(2)O)][As(8)V(13)NiClO(41)])(2) dimeric polyoxoanions and [Ni(en)(2)] groups which are linked together through vertexes forming a unique one-dimensional polymer. The study of the magnetic susceptibility of 1 demonstrates the presence of antiferromagnetic interaction in 1.

The hydrothermal reaction of CuBr2, CuBr and 1,10-phen gives birth to a 2-D coordination polymer [ Cu 4 II ( OH ) 4 (1,10-phen)4][ Cu 8 I Br 12 ] (1), consisting of the unique [ Cu 8 I Br 12 ] 4 - chains linked by the stepped-cubane copper(II)-hydroxo clusters [ Cu 4 II ( OH ) 4 ( phen ) 4 ] 4 + as the bridges. Compound 1 possesses high thermal stable. The non-linear optical property of 1 was studied, and the compound exhibits the reverse saturable absorption (α2 = 0.80 × 10−11 m W−1) and self-defocusing performance (n2 = −1.55 × 10−18 m2 W−1).

A novel cobalt phosphomolybdate: (NH 3 CH 2 CH 2 NH 3 )(NH 3 CH 2 CH 2 NH 2 ) 3 Na 3 [Co 4 Mo 12 O 24 (OH) 6 (H 2 O) 2 (HPO 4 ) 2 (PO 4 ) 6 ]·8H 2 O 1 , has been hydrothermally synthesized (200°C, 5 days, autogenously pressure) and characterized by IR, ESR, XPS, elemental analyses and X-ray crystallography. The crystal data: monoclinic space group C 2/ c , a =12.3281(3) A, b =21.5729(4) A, c =26.0242(5) A, β =99.5401°(3), V =6825(2) A 3 , Z =4, R 1 =0.0346, w R 2 =0.0650. The structure of compound 1 is based on Co[Mo 6 P 4 ] 2 units connected together via additional Co 2+ ions to give a new three-dimensional framework. The interconnected void and channels in the cobalt molybdophosphate frameworks are filled with counter cations and water molecules. The magnetic property of 1 exhibits antiferromagnetic coupling interactions.

Two novel coordination polymers of cobalt(II), [Co(µ3-H2bbh)(phen)]n (1) and [Co(µ4-H2bbh) (H2O)2]n (2) (phen = 1,10-phenanthroline; H4bbh = benzene-1,2,4,5-tetracarbo-1,2:4,5-dihydrazide), in which H2bbh ligands are in situ generated by an acylation reaction of H4bta (H4bta = benzene-1,2,4,5-tetracarboxylic acid) with hydrazine hydrate under hydrothermal conditions have been synthesized and structurally characterized. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

A novel cerium–adipate coordination polymer [Ce2(ad)3(H2O)2]n(1) has been hydrothermally synthesized and structurally characterized, which possesses three-dimensional network structure constructed from infinite chains of edge-sharing CeO8(H2O) polyhedron and long carbon chains. Each cerium cation binds to nine oxygen atoms belonging to six adipates and one water molecule, the adjacent cerium atoms are linked together through chelating-bridging and bidentate bridging carboxylates to form infinite polyhedron chains along [1 0 0] direction. The starlike distribution of six μ4-adipates around the central cerium generates a complicated network, which is thermally stable without any collapse even though no any guest molecules reside in the large channels.

The novel polyoxovanadate containing antimony [(C2N2H10)2β-{SbIII8VIV14O42(H2O)}](C2N2H8) · 4H2O has been synthesized from a mixture of VOSO4, Sb2O3, en and H2O under hydrothermal conditions. The spherical [β-{SbIII8VIV14O42(H2O)}]4− clusters form a one-dimensional double-chain structure with non-bonding Sb ⋯ O contacts.