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Three bimetallic organic-inorganic hybrids based on the [V2O6]2- building unit, [Cu(pty)(V2O6)]·H2O (1), [Cu(pty)(V2O6)] (2), [Cu(tpy)(V2O6)] (3), (pty = 4'-(4″-pyridyl)-2,2':6',2″-terpyridine, tpy = 2,2':6',2″-terpyridine), were synthesized via a one-pot method. Hybrid 1 has a 1D straight chain architecture with [V2O6]2- clusters and Cu-pty complexes; hybrids 2 and 3 possess a 2D sheet structure including 10-membered rings assembled from four [Cu(pty)]2+ motifs and six [V2O6]2- clusters in 2, and two [Cu(tpy)]2+ units and eight [V2O6]2- clusters in 3. Noteworthy, hybrids 1-3 can be employed as bifunctional electrocatalysts for electroreduction of nitrite and electrooxidation of ascorbic acid. Additionally, theoretical calculations including the molecular electrostatic potential and the frontier molecular orbital were performed to estimate the electronic structure of hybrids 1-3. The natural bond orbital analysis was also calculated to interpret the electron charge distribution.

A mild and environmentally friendly method to synthesize half-sandwich ruthenium complexes through the Wittig reaction between an aldehyde-tagged half-sandwich ruthenium complex and phosphorus ylide mechanochemically is reported herein. The mechanochemical synthesis of valuable half-sandwich ruthenium complexes resulted in a fast reaction, good yield with simple workup, and the avoidance of harsh reaction conditions and organic solvents. The synthesized half-sandwich ruthenium complexes exhibited high catalytic activity for transfer hydrogenation of ketones using 2-propanol as the hydrogen source and solvent. Density functional theory was carried out to propose a mechanism for the transfer hydrogenation process. The modeling suggests the importance of the labile p-cymene ligand in modulating the reactivity of the catalyst.

By application of a newly designed T-shaped ligand 5-(4-pyridin-4-yl-benzoylamino)isophthalic acid (H2PBAI) to assemble with Zn(II) ions under solvothermal conditions, a novel porous polyhedral metal-organic framework (Zn-PBAI) with pcu topology has been obtained. When treated as a precursor by annealing of Zn-PBAI at various temperatures, porous carbon polyhedra (PCP) were prepared and tested as an anode material for lithium-ion batteries. The results show that PCP carbonized at 1000 °C (PCP-1000) manifest the highest reversible specific capacity of about 1125 mAh g-1 at a current of 500 mA g-1 after 200 cycles, which is supposed to benefit from the large accessible specific area and high electric conductivity. Moreover, PCP-1000 electrode materials also exhibit superior cyclic stability and good rate capacity.

Six new heteropoly compounds in the [M4(H2O)2(As2W15O56)2]16- series (M = CuII, MnII, CoII, NiII, ZnII, CdII), previously unknown, were synthesized and characterized by means of IR, UV-vis, CV, 183W NMR, TG-DSC, and elemental analyses. The synthetic method used in preparing this type of heteropoly compounds was different from that in preparing the corresponding tungstophosphates in that the starting materials were transition metal chlorides in 1.5 times the stoichiometric amount and the required pH value is lower than 2. The crystal structure of Na16[Cu4(H2O)2(As2W15O56)2].47H2O was solved in triclinic, P1 symmetry, with a = 12.721(3) A, b = 24.516(5) A, c = 26.450(5) A, alpha = 89.90(3) degrees, beta = 77.32(3) degrees, gamma = 89.96(3)degrees, V = 8048(3) A3, Z = 2, and R = 0.0966. This anion is isostructural with the previously reported [Cu4(H2O)2(P2W15O56)2]16-, having a rhombic tetrameric cluster Cu4O16 sandwiched by two trivacant Dawson-Wells anions [As2W15O56]12-. The range of the bond lengths of the equatorial Cu-O bonds is 1.83-2.05 A, while that of the axial Cu-O bonds is 2.30-2.39 A. The distortion of the Cu4O16 cluster is smaller in the As species than in the P species. Two copper atoms in the Cu4O16 cluster are coordinated by water molecules. The replacement reactions of the coordinated water molecules of this series of heteropoly compounds in aqueous solutions and in selected organic solvents are also reported here for the first time. The results show that [Fe(CN)6]4-, [Fe(CN)6]3-, H2NCH2CH2NH2, etc., can replace the coordinated water to form its characteristic color in aqueous solutions, while in organic solvents the coordinated water molecules are lost, leaving unshared coordination positions that can be occupied by some organic ligands such as pyridine, lactic acid, and acetone to restore the octahedral coordination of M2+. The crystallographic morphologies of this series of heteropolyanions after phase transfer are dependent on different transition metal ions present in the central M4O16 clusters although the anions are isostructural with each other.

An in situ ligand reaction from the pyridine cycle to -COO- in the copper-organic framework is achieved under hydrothermal conditions. Compound [Cu 2 (bpa) 4 ] [1; bpa = 5-(4-bromophenyl)picolinic acid] exhibits a one-dimensional chain architecture based on weak Cu-O interactions. The mechanism of ligand transformation is discussed.

A novel three-dimensional copper molybdate with mixed ligands, [{CuII(2,2‘-bpy)}{CuII(IN)2}{Mo4O12(OH)2}] (IN- = isonicotinate ion, 2,2‘-bpy = 2,2‘-bipyridine), 1, has been hydrothermally synthesized and structurally characterized, and this compound is built from an unprecedented tetranuclear molybdenum oxide cluster covalently bonded to two types of copper complex fragments, {CuII(2,2‘-bpy)}2+ and {CuII(IN)2}, via terminal oxygen atoms of {MoO6} octahedra. Crystal data for compound 1: monoclinic, space group C2/c, a = 16.4755 A, b = 10.3714 A, c = 17.4382 A, α = 90.0000°, β = 94.8098°, γ = 90.0000°; V = 2969.24 A3; Z = 2. Variable temperature magnetic susceptibility indicates that both ferromagnetic and antiferromagnetic interactions exist in 1.

The synthesis and characterization of microtubes of SiMoW(11) Keggin polyoxometalates containing either an Mo(V) or Mo(VI) atom is reported. The introduction of a Mo atom into the Keggin-type tungstosilicate microtubes endows them with new properties. The Mo-substituted microtubes may exert both W and Mo functionalities in electrocatalytic reactions and in the immobilization of noble metal nanoparticles. The degree of reduction of the Mo component in the SiMoW(11) microtubes is controllable simply by tuning the amount of reductant present in the mother liquor. Mo-substituted Keggin tungstosilicate microtubes in their reduced state are more stable than the all-tungsten Keggin tungstosilicate heteropoly blue microtubes.

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))].2H(2)O (4) [btb = 1,4-bis(1,2,4-triazol-1-yl)butane], were hydrothermally synthesized through use of the same Keggin polyoxometalate as the template and tuning the molar ratio of the bis(triazole) ligand to the Cu(II) ion. The ratio of the bis(triazole) ligand to Cu(II) has a crucial influence on the structures of this series. Single-crystal X-ray diffraction analyses indicate that compound 1 is constructed by tetranuclear ring-connecting chains and polymerized [Cu(bte)](+) chains, between which SiW(12) anions are inserted to form a three-dimensional (3D) structure. Compound 2 shows a (4(4).6(2)) two-dimensional grid sheet. The discrete SiW(12) anions are sandwiched by the sheets, just like "hamburgers". Compound 3 presents channel-like [Cu(2)(btb)](2+) polymerized chains, which are further connected by SiW(12) anions to construct a 3D framework. Compound 4 exhibits a (6(6)) 3D Cu-btb framework with hexagonal channels, into which the tetradentate SiW(12) anions are incorporated. The thermal stabilities of the compounds are discussed.

Four new hybrids based on the Wells-Dawson polyoxometalate [P2W18O62](6-) (P2W18), ([Ag(bipy)]2[P2W18O62]).2[H2bipy].4H2O (1), ([Ag(bipy)]4[P2W18O62]).2[Hbipy](2), K[P2W18O62].2.5[H2bipy].2H2O (3), and [P2W18O62] 2.[H2bipy]4.[Hbipy]4 .3H2O (4), were hydrothermally synthesized and structurally characterized by routine techniques and single-crystal X-ray diffraction. Compounds 1 and 2 are isolated at lower pH values. 1 represents a 3D (4,4)-net structure with NbO topology, in which the P2W18 clusters are modified by four Ag-N coordination polymeric chains, and 2 exhibits a 3D (3,4)-net structure with the (9(2).12)(8.10(4).12)(3(2).10(2).11(2))(3.6.10(2).12(2)) topology, in which Ag-bipy layers are intercalated by the dimer of P2W18 clusters in a staggering mode, and the P2W18 clusters show the highest coordination number to date. By increasing the pH value, compounds 3 and 4 are obtained as supramolecular compounds. Their structural differences reveal that the pH value of the reaction system is the key factor influencing the structure and topology of these compounds, which can be explained by the acid-base chemistry of the molecular building units and silver chemistry.

Organometallic products formed from the reaction of an electrophilic iron carbene complex with nitrosoarenes or azobenzene reflect net insertion of the ArN{double bond}X moiety into the Fe{double bond}CHAr bond. Cp(CO){sub 2}Fe-O-N(Ar{prime}){double bond}CHAr{sup +} and Cp(CO){sub 2}FeN(Ph)-N(Ph){double bond}CHAr{sup +} (Ar = p-C{sub 6}H{sub 4}OMe, Ar{prime} = p-C{sub 6}H{sub 4}NMe{sub 2}) have been isolated and spectroscopically characterized; the crystal structure of Cp(CO){sub 2}Fe-O-N(Ph){double bond}CHAr{sup +} is reported. Exposure of acetone solutions of Cp(CO){sub 2}Fe-O-N(Ar{prime}){double bond}CHAr{sup +} or Cp(CO){sub 2}FeN(Ph)-N(Ph){double bond}char{sup +} to light yields imine products Ar{prime}N{double bond}CHAr or PhN{double bond}CHAr, respectively. There is no evidence to support the formation of the simple stoichiometric iron-containing products of these reactions, the oxo and nitrene complexes Cp(CO){sub 2}Fe{double bond}O{sup +} and Cp(CO){sub 2}Fe{double bond}NPh{sup +}. Hydrolysis of the nitrone complexes Cp(CO){sub 2}Fe-O-N(Ar{prime}){double bond}CHAr{sup +} in aqueous acetone yields aldehyde products Ar{prime}CHO. 30 refs., 1 fig., 4 tabs.

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. Single-crystal X-ray diffraction analysis reveals that compound 1 exhibits a unique (3,4,6)-connected 3D framework with a (6(2).8(1))2(8(3))2(6(4).8(2))2(6(1).8(14)) topology, constructed from {AsMo12O40(VO)[VO(H2O)]}5- polyoxoanions modified by six {Cu(bipy)}n coordination polymeric chains. The asymmetrical polar coordination mode has never been found in the POM chemistry hitherto. It is also the first example of the bivanadium-capped POM as an anionic template to construct a 3D framework with the highest connection number of bicapped POMs. Additionally, by just changing the length of the organic ligand, a new compound {[AsMo12O40(VO)2][Cu(bpe)]2}.[Cu(bpe)].[H2bpe].H2O (2) (bpe = bis(4-pyridyl)ethylene), has been obtained, in which the {AsMo12O40(VO)2} sections are modified by double monotrack {Cu(bpe)}n coordination polymeric chains to form a "rail-like" 1D structure.

By introducing the flexible 1,1'-(1,4-butanediyl)bis(imidazole) (bbi) ligand into the polyoxovanadate system, five novel polyoxoanion-templated architectures based on [As(8)V(14)O(42)](4-) and [V(16)O(38)Cl](6-) building blocks were obtained: [M(bbi)(2)](2)[As(8)V(14)O(42)(H(2)O)] [M = Co (1), Ni (2), and Zn (3)], [Cu(bbi)](4)[As(8)V(14)O(42)(H(2)O)] (4), and [Cu(bbi)](6)[V(16)O(38)Cl] (5). Compounds 1-3 are isostructural, and they exhibit a binodal (4,6)-connected 2D structure with Schläfli symbol (3(4) x 4(2))(3(4) x 4(4) x 5(4) x 6(3))(2), in which the polyoxoanion induces a closed four-membered circuit of M(4)(bbi)(4). Compound 4 exhibits an interesting 3D framework constructed from tetradentate [As(8)V(14)O(42)](4-) cluster anions and cationic ladderlike double chains. There exists a bigger M(8)(bbi)(6)O(2) circuit in 4. The 3D extended structure of 5 is composed of heptadentate [V(16)O(38)Cl](6-) anions and flexural cationic chains; the latter consists of six Cu(bbi) segments arranged alternately. It presents the largest 24-membered circuit of M(24)(bbi)(24) so far observed made of bbi molecules and transition-metal cations. Investigation of their structural relations shows the important template role of the polyoxoanions and the synergetic interactions among the polyoxoanions, transition-metal ions, and flexible ligand in the assembly process. The magnetic properties of compounds 1-3 were also studied.

Microtubes of alpha-K4SiW12O40 with the length around 1 cm and inner diameter and wall thickness in the ranges of 7-55 mum and 3-15 mum, respectively, were copiously fabricated by a one-step, template-free aqueous synthesis. The formation mechanism is discussed. The discovered tubular structure of the polyoxometalate is believed to be promising for use in templates, as a precursor of tungsten oxide ceramic microtubes, and for other uses associated with tubular structures.

A novel three-dimensional copper molybdate with mixed ligands, [[Cu(II)(2,2'-bpy)][Cu(II)(IN)(2)][Mo(4)O(12)(OH)(2)]] (IN(-) = isonicotinate ion, 2,2'-bpy = 2,2'-bipyridine), 1, has been hydrothermally synthesized and structurally characterized, and this compound is built from an unprecedented tetranuclear molybdenum oxide cluster covalently bonded to two types of copper complex fragments, [Cu(II)(2,2'-bpy)](2+) and [Cu(II)(IN)(2)], via terminal oxygen atoms of [MoO(6)] octahedra. Crystal data for compound 1: monoclinic, space group C2/c, a = 16.4755 A, b = 10.3714 A, c = 17.4382 A, alpha = 90.0000 degrees, beta = 94.8098 degrees, gamma = 90.0000 degrees; V = 2969.24 A(3); Z = 2. Variable temperature magnetic susceptibility indicates that both ferromagnetic and antiferromagnetic interactions exist in 1.