Hai-Juan Du

Construction and isomeric transformation of polyoxometalates directed by 1,ω-bis(pyridinium)alkane templates

Ten novel inorganic–organic hybrid polyoxometalates, namely, [1,3-bis(pyridinium) propane]2[α-Mo8O26] (1), [1,4-bis(pyridinium)butane]2[1D-Mo8O26] (2), [1,5-bis(pyridinium)pentane]2[θ-Mo8O26] (3), [1,6-bis(pyridinium)hexane]2[1D-Mo8O26] (4), [1,7-bis(pyridinium)heptane]2[β-Mo8O26] (5), [1,8-bis(pyridinium)octane]2[θ-Mo8O26] (6), [1,9-bis(pyridinium)nonane]2[(α + β)-Mo8O26] (7), [1,10-bis(pyridinium)decane]2[β-Mo8O26] (8), [1,11-bis(pyridinium)undecane]2[β-Mo8O26] (9), [1,12-bis(pyridinium)dodecane]2[γ-Mo8O26] (10), (Scheme 1) were synthesized by cation templated self-assembly with octamolybdate anions under hydrothermal reaction conditions. Crystal data analysis revealed that these compounds were all composed of discrete organic cations and polyacid anions [Mo8O26]4− interacting by electrostatic and hydrogen bond interactions. Interestingly in these compounds the anion fraction could take on α-, β-, θ-, γ-[Mo8O26]4− 0D isomers or rare 1D- polymeric frameworks with a simple length modification of the alkane components. Moreover, these polyacid compounds had definite catalytic activities on the oxidation reaction of acetaldehyde to acetic acid and the relationship of structure/catalytic activities were initially demonstrated.

Crystal structures and photocatalytic properties of two novel iodoplumbate hybrids templated by multivalent organic cations

Two novel complexes based on multivalent organic cations and PbI2, {(tbp)2[Pb3I12]}n (1) (tbp = 1,3,5-tri(N-pyridinium methyl)benzene tribromide) and {(tbpm)[Pb3I9]·H2O}n (2) (tbpm = 1,3,5-tri(4-methylpyridiniummethyl) benzene tribromide), have been synthesized and characterized by X-ray diffractometry. Compound 1 has a trinuclear structure and compound 2 presents a new 1D iodoplumbate. Photochemical studies reveal the good photocatalytic performances of the two iodoplumbate hybrids. Furthermore, the side chains effect on the fabrication of the iodoplumbate and the photocatalytic performances was also investigated.

An unprecedented ι-type octamolybdate: [TbI1]2[(β-Mo8O26)0.5(ι-Mo8O26)] directed by a new tricationic template

Trication-templated assembly of POMs resulted in an unprecedented ι-type octamolybdate configuration. The ι-[Mo8O26]4− cluster is composed of five {MoO6} octahedra and three {MoO4} tetrahedra via an edge-sharing and corner-sharing arrangement to form a cabas-like cluster, which represents the ninth isomer of octamolybdates.

Four hybrid compounds based on a new type of molybdates and a flexible tripodal ligand: synthesis, structures, photochemical and electrochemical properties

The hydrothermal reaction of a mixture of (NH4)6Mo7O24·4H2O, a flexible tripodal ligand 1,3,5-tris-(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (TITMB) and metal salts at different temperatures resulted in four novel compounds, namely [H2TITMB]2[Mo12O38]·4H2O (1), [Zn(Mo2O7)(TITMB)] (2), [H3TITMB]2[Cd(β-Mo8O26)(H2O)2(α-Mo8O26)]·4H2O (3) and [H3TITMB]2[Co(β-Mo8O26)(H2O)2(α-Mo8O26)]·4.5H2O (4). The structures of compounds 1, 2, 3 and 4 were explored with IR spectroscopy, thermal gravimetric analysis (TGA), PXRD, UV-vis diffuse reflectance spectra and single-crystal X-ray diffraction in the solid state. In 1 the new type of isopolymolybdate unit [Mo12O38]4− shared ten distorted {MoO6} octahedra and two distorted {MoO5} tetragonal pyramid with four kinds of O atoms. And the unprecedented bimetallic oxide chain [Zn(Mo2O7)]n in compound 2 consisted of trigonal bipyramids and octahedra through sharing edges. Both compounds 3 and 4 are 3-D octamolybdate-based inorganic–organic hybrids consisting of the polyacid [α-Mo8O26]4− anions and novel infinite chains of [β-Mo8O26]4− anions covalently linked through [Cd(H2O)2]2+ groups or [Co(H2O)2]2+ groups. In addition, the electrochemical behavior and photocatalytic activities of the title compounds were also investigated.

Syntheses and characterization of two novel 1D Pb(II) Halide supramolecular polymers possessing incomplete Cubane subunit directed by π -conjugated Dication templates

AbstractTwo novel cation-templated complexes, {(1, 4-PMBP)[Pb4I10] ⋅DMF}n(1) {(DBBP)2[Pb5I8Br6]}n(2), (1,4-PMBP ⋅2Br =1,1”-[1,4-phenylene-bis(methylene)]bis-4,4’-bipyridinium dibromide; DBBP ⋅2Br = N, N’-dibenzyl- 4, 4’-bipyridinium dibromide) have been synthesized via the self-assembly reaction in solution. X-ray crystallography showed that compounds 1 and 2 can be regarded as 1D iodoplumbate examples which contain incomplete cubane subunit directed by π-conjugated dication templates. It is the H-bonds and electrostatic interactions between the organic counter cations and inorganic moieties that contribute the crystal packing. These compounds have been further characterized by IR spectroscopy, UV-Vis spectra, elemental analysis and thermostability properties. Graphical AbstractWe report two novel 1D iodoplumbate supramolecular polymers which contain incomplete cubane subunit based on л-conjugated dication templates. These compounds have been further characterized by IR, UV–Vis spectra, elemental analysis and thermostability tests.

Six cation-templated halometal complexes and C–H activation of alkylene-bridged azoles

Six dication-templated complexes were discovered in efforts to investigate the effect of linear imidazolium-based template, 1,ω-bis(3,3′-methylimidazolium)alkyl dibromide, on pure inorganic halometal clusters. Complexes {[C4(Mim)2](Pb2I6)}n (1) (ω = 4), {[C1(Mim)2] (Ag2I4)}n (2) (ω = 1), {[C3(Mim)2](Ag2I4)}n (3) (ω = 3), and {[C4(Mim)2](Ag2I4)}n (4) (ω = 4) possess 1-D chain architecture with different organic cations trapped in it. Compound {[C3′(Mim)2](CuBr3)} (5) (ω = 3) contains the mononuclear anion (CuBr3)2− and intra-molecular coupled organic cation with the formed seven-membered ring. {[C2(Mim)2S2]2(Cu2I2)}n (6) (ω = 2) presents an infinite 2-D coordination polymer as the first representative polyrotaxane example featuring the biimidazolium thiolate cation ligand. All compounds were further characterized with IR spectra and thermal analysis properties. Four bis(N-heterocyclic carbene) precursors together with the cyclization and thiolation products were utilized to construct six dication-templated metal halides from 0,1 to 2-D polypseudorotaxane.

Syntheses, Crystal Structures, and Catalytic Activities of Two Inorganic–Organic Hybrid Materials: [py]2[Hpy]3[PMo12O40]·H2O and [btx]2[Mo8O26]·H2O

Two novel organic–inorganic hybrid supramolecular compounds based on organic cations and POMs, namely, [py]2[Hpy]3[PMo12O40]·H2O (1) and [btx]2[Mo8O26]·H2O (2) [btx = 1,6-bis(triethylmethylammonium)xylol], have been hydrothermally synthesized and characterized by single-crystal x-ray diffraction, infrared (IR) spectroscopy, and thermal gravimetric analysis (TGA). The compound 1 crystallizes in the monoclinic, space group P2(1)/c with a = 17.7932(18) Å, b = 19.427(2) Å, c = 15.2515(16) Å, β = 98.479(2)°. Compound 2 crystallizes in the triclinic, space group P-1 with a = 11.6245(8)Å, b = 11.9573(13)Å, c = 12.8756(10)Å, α = 63.830(6)°, β = 75.285(5)°, γ = 68.024(5)°. Compound 1 contained the classical Keggin-type discrete [PMo12O40]3− anion and 2 had the a-[Mo8O26]4− cluster. Moreover, it was indicated that these polyacid compounds had definite catalytic activities on the reaction of acetaldehyde oxidation to acetic acid.

Synthesis and Crystal Structure of an Inorganic-Organic Hybrid Material: [1,1′-dibutyl-4,4′-bipyridinium][α-Mo8O26]0.5

A novel inorganic–organic hybrid polyoxometalate, [1,1′-dibutyl-4,4′-bipyridinium,][α-Mo8O26]0.5 (1), has been synthesized by the cation-templated self-assembly with octamolybdate anions under hydrothermal reaction conditions. The structure has been determined by single-crystal X-ray diffraction analysis and further characterized by PXRD, IR spectra, and elemental analysis. The crystal data analysis revealed that the compound was composed of one discrete [1,1′-dibutyl-4′-bipyridinium]2+ cation and 0.5 polyacid anions [Mo8O26]4– interacted by electrostatic interactions. In the compound the anion fraction take on a [α-Mo8O26]4– cluster.

A new Mo/S/Cu polymeric cluster: Synthesis, structure and properties

Compound {(MoOS3Cu3Br(-bpy)2.5)·0.75DMF}∞ is an isomorphous neutral 3D 4-fold interpenetrating architecture displaying self-interpenetrating feature.sometimes, the compound like the art. All of it have been characterized by single-crystal X-ray diffraction, elemental analysis, IR, TGA, and UV-vis. The results may provide fascinating insights into template effect on the construction of the cluster-based coordination polymers.

Synthesis and Characterization of Two New Polymolybdate Clusters Containing Chlorine Based on Mo-POMs and N-heterocycle Templates

Two new organic-inorganic hybrid materials based on Mo-polyoxometalates and N-heterocycle templates, namely [Ag3 (DIE)6][Mo12O36·ClO4]2 ·Cl (1), and [(IM)4NH4] [Mo12O36·ClO4] (2) [DIE = 1,2-diimidazoloethane, IM = imidazole] have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compounds 1 and 2 possess the classical keggin-type heteropolyoxoanion with Cl as the center atom, and this is the first case. IR spectroscopy and gravimetric analysis were performed to further characterize these compounds.