Catalytic epoxidation of olefin over supramolecular compounds of molybdenum oxide clusters and a copper complex

The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu（bipy）]4[Mo15O47].2H2O （1） and [Cu1（bix）][（Cu1bix） （δ-MoVl8O26）0.5] （2） （bipy = 4,4＇-bipyridine, bix = 1,4-bis（imidazole-1-ylmethyl）benzene）. Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide （t-BuOOH） as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates.

Syntheses, Crystal Structures, Thermal and Fluorescent Properties of Two New Bearing Bi(Ⅲ) Supramolecular Compounds

Two new bearing Bi(Ⅲ) supramolecular compounds [Bi(pydcH)_(3)(Bi(pydcH)(pydcH_(2))(pydc)(Bi(pydcH)(pydcH_(2))(pydc)](1) and {[Bi(pydcH)_(3)]·(H_(2)O)_(5)(Dmap)}_(2)(2) have been successfully synthesized via hydrothermal reaction(pydcH_(2) = 2,6-pyridine dicarboxylate, Dmap = 4-dimethylamiopyridine). They have been structurally determined by single-crystal X-ray analysis, and characterized by fluorescence analysis and thermogravimetric analysis(TG). Both compounds 1 and 2 are of the same triclinic system with different structures. The decomposition mechanisms of compounds 1 and 2 are discussed. Compared to 1, lots of small molecules were possibly removed from compound 2 below 250 ℃. In addition, the photoluminescence properties were also investigated.

Hydrothermal Synthesis,Crystal Structure and Fluorescence Spectrum Studies of a Supramolecular Compound {[2-(2-Pyridyl)benzimidazoleH_2]^(2+)·[SbCl_5]^(2-)}_2

A new supramolecular compound, { [2-（2-pyridyl）benzimidazoleH2]2＋.[SBC15]2-}2, was synthesized by the hydrothermal reaction of o-diaminobenzene, 2-pyridinecarboxylie acid and SbCl3 in 1：1 HC1 solution, and characterized by chemical analysis, elemental analysis, IR spectra, thermogravimetfic analysis and fluorescence spectra. The crystal structure was deter- mined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P211c, with a = 16.0397（13）, b = 14.3189（12）, c = 15.6370（13） A, β = 105.8980（10）°, V = 3454.0（5） A3, Z = 4, C24H22Cl10N6Sb2, Mr = 992.48, Dc = 1.909 g/cm3,/z = 2.366 mm-1, S = 1.010, F（000） = 1920, R = 0.0254 and wR = 0.0555. The coordination anion, [SbCl5]2- which is a distorted tetragonal pyramid, is composed by coordinating action with Sb3＋ ion and five adjacent chloride ions. Every four coordination anions of [SbCl5]2- form a biquaternion ring structure through the secondary bonding of Sb...Cl. Moreover, the compound adopts a three-dimensional network supramolecular structure because of the hydrogen bonds and π-π stacking between the rings and the 2-（2-pyridyl）benzimidazole divalent cations. The title compound also shows good fluorescent behaviors.

Synthesis and Structural Characterization of a Supramolecular Compound [(C_8H_9NO_2)·HgI_2]_n Constructed from Hg…I and C–H…O Linkage

The title complex [（C8H9NO2）·HgI2]n has been synthesized from the reaction of pyridine-3-ethylformate with mercury iodide in the mixture of DMF and absolute methanol. Its structure was determined by IR, elemental analysis and X-ray single-crystal diffraction analysis. The crystal is of monoclinic system, space group P21/n with a = 4.3397（5）, b = 25.051（3）, c = 12.3719（13）A, β = 92.2130（10）°, CsH9HgI2NO2, Mr = 605.55, V = 1344.0（3）A^3, Z = 4, Dc = 2.993 mg·m^-3, F（000） = 1064, μ = 16.024 mml, the final R = 0.0258 and wR = 0.0504. In the title complex, the center Hg（II） exhibits a four-coordinated distorted tetrahedral geometry. A three-dimensional network arrangement is presented via Hg…I weak interactions among adjacent molecules.

Synthesis,Structure and Electrochemical Property of a Supramolecular Compound(H_2en)_2[Cu(en)_2(H_3O)_2][Mo_8O_(28)]

A supramolecular compound（H2en）2[Cu（en）2（H3O）2][Mo8O28]（en=ethylenediamine） was hydrothermally prepared and confirmed by elemental analysis and TG analysis.Single-crystal X-ray analysis reveals that the crystal crystallizes in the triclinic system,space group P1 with a=9.4635（4）,b=9.8645（5）,c=10.9794（5）A,α=69.2050（10）,β=72.3730（10）,γ=78.4510（10）o,Mr=1559.55,V=908.24（7）A^3,Z=1,Dc=2.851 g/m^3,F（000）=749,μ=3.350 mm^-1,S=1.000,the final R=0.0217 and wR=0.0567.The compound consists of（H2en）^2＋,[Mo8O28]^8-anion and [Cu（en）2（H3O）2]^2＋ cations and constructs a 3D supramolecular structure through hydrogen bonds between the nitrogen atoms from en of [Cu（en）2（H3O）2]^4＋ fragments and the terminal oxygen atoms from the [Mo8O28]^8-polyoxoanions.The electrochemical behavior of this compound has been studied in detail based on a solid bulk modified carbon paste electrode of compound（CPE）.

Hydrothermal Synthesis,Crystal Structure and Fluorescence Spectrum Studies of a Novel Supramolecular Compound {[2-(2-Pyridyl)benzimidazoleH_2]_2·[BiCl_6]·Cl}

A novel supramolecular compound,{[2-（2-pyridyl）benzimidazoleH2]2·[BiCl6]·Cl},was synthesized by the hydrothermal reaction of o-phenylenediamine and α-pyridinecarboxylic acid with BiCl3 in 6.0 mol·L-1 HCl solution,and characterized by elemental analysis,IR,X-ray single-crystal diffraction and photoluminescence spectroscopy.The crystal （C24H22N6Cl7Bi,Mr= 851.61） belongs to the triclinic system,space group P1 with a =7.2887（18）,b =9.548（2）,c= 12.469（3）,α=85.306（4）,β=82.814（4）,γ=71.349（4）°,Z=1,V=814.9（3）3,Dc=1.735 g/cm3,μ（MoKα）=6.007 mm-1,F（000）=410,R=0.0307 and wR=0.0787.The bismuth ion and six chlorine ions construct a distorted octahedral configuration.The three-dimensional supramolecular network is built from electrostatic attractions,hydrogen bonds and π-π interaction between the BiCl6 anion,Cl anion and [2-（2-pyridyl）benzimidazoleH2] cation.The photoluminescence spectroscopy study shows that the title compound has a blue fluorescent emission at 450 nm in the solid state.

Synthesis and Structure of a Novel Supramolecular Compound [Co(2,2′-bipy)(H_2O)_4 ][trans-1,4-chdc] and Separation of Isomer of 1,4-Cyclohexanedicarboxylic Acid

A supramolecular compound, [ Co（2,2＇-bipy） （ H2O）4 ] [ trans-1,4-chdc ] （ compound 1 ） （ 2,2＇-bipy = 2,2＇- bipyridine, 1,4-chdcH2 = 1,4-cyclohexanedicarboxylic acid）, was synthesized and characterized by single-crystal Xray diffraction analysis, IR spectrometry, TG analysis, and elemental analyses. Single-crystal X-ray diffraction analysis revealed that [ Co（ 2,2＇-bipy） （ H2O）4 ]^2＋ units and adjacent 1,4-chdc^2- formed a single layer by hydrogen bonding and electrostatic interactions along the ac-plane, and two symmetry-related single layers interacted with each other by hydrogen bonding, resulting in a double layer, which further formed a 3-D structure by π-π stacking. The most attractive structural feature of compound 1 is that 1,4-chdc2- possesses only tram-conformation although there are both c/s- and tram-conformations in the raw material.

Synthesis and Crystal Structure of a Novel Three-dimensional Supramolecular Compound [(AgI_3)(4-HBPFA)_2(H_2O)]

The supramolecular compound [(AgI3)(4-HBPFA)2(H2O)] (Mr = 1361.11) was synthesized via the reaction of 1,1?-bis[(4-pyridylamino)carbonyl]ferrocene (4-BPFA) with AgI, and structurally characterized by single-crystal X-ray diffraction analysis. Crystal data: monoclinic, space group C2/c, a = 1.6783(3), b = 10.646(2), c = 2.5419(5) ?, β = 93.66(3)o, V = 4532.2(16) ?3, Z = 4, Dc = 1.995 g/cm3, F(000) = 2632 and μ = 3.158 mm-1. The compound consists of (4- HBPFA)+, (AgI3)2- and H2O. In the structure, the adjacent (4-HBPFA)+ are linked by C–H…O and N–H…N hydrogen bonds into 1-D chains which are further linked by C–H…I and N–H…I hydrogen bonds as well as intermolecular π-π stacking interactions to form a 3-D supramolecular compound.

A coordination compound featuring a supramolecular hydrogen-bonding network for proton conduction

A new coordination compound [Mg（L）（H2 O）5·H2 O]（NKU-109, H2 L=5-（4 H-1,2,4-triazol-4-yl）benzene-1,3-dicarboxylic acid） was solvothermally synthesized, featuring a supramolecular hydrogen-bonding network. A good proton conductivity of 5.87×10^-4S/cm was recorded at 70℃ and a relative humidity of75% in alternating current（AC） impedance experiment, which sheds a new light on the design of proton conduction materials based on coordination compounds.

Construction of a Ytterbium Supramolecular Compound from 5,5＇-（Buta-diyne- 1,4-diyl）diisophthalic Acid

A novel 3D ytterbium supramolecular compound, [Yb（HBDDC）（H20）4]·2H2O（1）, was synthesized via 5,5＇-（buta-diyne-1,4-diyl）diisophthalic acid ligand（HaBDDC） under solvothermal conditions. Single-crystal X-ray diffraction analysis reveals that compound 1 crystallizes in triclinic system, PT space group with a=0.71372（14） nm, b=1.0566（2） nm, c=1.7969（4） nm, a=101.01（3）°, β=98.15（3）°, γ=99.17（3）° and V=1.2922（4） nm3. Compound 1 exhi- bits a special infinite 1D chain, which stacks parallel each other in an ABAB sequence, leading to the formation of a 3D supramolecular structure owing to the strong π-π interactions between adjacent phenyl ring groups. Moreover, compound 1 manifests excellent luminescent property.