Thermal dehydration of Y(TFA)3(H2O)3: Synthesis and molecular structures of [Y(μ,η1:η1-TFA)3(THF)(H2O)]1∞ · THF and [Y4(μ3-OH)4(μ,η1:η1-TFA)6(η1-TFA)(η2-TFA)(THF)3(DMSO)(H2O)] · 6THF (TFA = trifluoroacetate)

In order to obtain a better anhydrous precursor for various applications in materials science and catalysis, thermal dehydration reactions of Y(TFA)₃(H₂O)₃ (TFA = trifluoroacetate) (A) were investigated. Thermal treatment of A at different temperatures under vacuum (5 × 10^?2 mm) for several hours failed to give totally anhydrous yttrium trifluoroacetate (as indicated by IR). Two different complexes, a partially dehydrated [Y(μ,η¹:η¹-TFA)₃(THF)(H₂O)]_1∞·THF (1) and a partially hydrolyzed [Y₄(μ₃-OH)₄(μ,η¹:η¹-TFA)₆(η¹-TFA)(η²-TFA)(THF)₃(DMSO)(H₂O)] · 6THF (2), were obtained with good and moderate yield, respectively, by crystallization of two different thermally treated batches of A from THF (or THF + DMSO) at room temperature. More efficient dehydration of A could be achieved at 200 °C in a furnace, the obtained anhydrous yttrium tris-trifluoroacetate giving Y(TFA)₃(THF)₂ (3) on crystallization from THF. All the products were characterized by elemental analyses, FT-IR and ¹H NMR spectroscopy as well as thermo-gravimetric analysis. In addition, single crystal X-ray structures are reported for 1 and 2, which show either a terminal (η¹ and η²) or bridging (μ,η¹:η¹) bonding behavior of the TFA ligand.     

The novel ligand 4′-phenyl-3,2′:6′,3′′-terpyridine (L) and the supramolecular structure of the dinuclear complex [Zn2(μ-L)(acac)4] · H2O (acac = acetylacetonato)

The new terpyridyl ligand 4′-phenyl-3,2′:6′,3′′-terpyridine (L) reacts with Zn(acac)₂ to produce the dizinc complex [Zn₂(μ-L)(acac)₄] · H₂O (1) (acac = acetylacetonato). The analysis of the crystal structure of this zero-dimensional (0D) complex shows the existence of two Zn(acac)₂ centers bridged symmetrically by one μ-L ligand. The key role played by the acac and L ligands and the guest water molecule allows the generation of a series of intermolecular hydrogen bonds of the O–H/O, C–H/O and C–H/π type which give raise to a 3D supramolecular array. The observed C–H/π interactions are so widespread that all the π-rings present in the structure, viz., those belonging to the L ligand as well as the acetylacetonato chelate rings, participate as hydrogen bond acceptors.     

Microparticles of α-Bi2O3 Obtained from Bismuth Basic Nitrate [Bi6O6(OH)2(NO3)4·2H2O] with Photocatalytic Properties

Topics in Catalysis - Alpha phase bismuth oxide (α-Bi2O3) microparticles were prepared through the annealing at 600 °C of basic bismuth nitrate [Bi6O6(OH)2(NO3)4·2H2O]...     

[Co(Ⅱ)(H2O)6](C4H4O4)·2C6H12N4·4H2O修饰电极电化学催化谷胱苷肽研究

利用气相沉积法研制了基于TiO2凝胶固定化[Co(H2O)6](C4H4O4).2C6H12N4.4H2O(CoL)修饰电极。研究了该修饰电极对谷胱苷肽(GSH)的催化活性,发现在pH 7.5,0.1 mol/L NaAc-HAc的缓冲溶液中,CoL对电氧化GSH浓度之间有较好的线性关系.线性范围为2×10-6~1×10-4mol/L,检测下限为8×10-7mol/L,相对标准偏差为2.0%(cGSH=5×10-6mol/L,n=6)。应用该法测定生物样品中谷胱苷肽的含量并与紫外分光光度法进行对照,结果一致。     

Divalent metal complexes of formylhydrazine: Syntheses and crystal structures of M(CH4N2O)2(H2O)2·2NO3 (M = Zn,Co)

The syntheses and crystal structures of Zn(CH₄N₂O)₂(H₂O)₂·2(NO₃) (1) and Co(CH₄N₂O)₂(H₂O)₂·2(NO₃) (2), the first well-characterised metal complexes of formylhydrazine (fh), are described. In both compounds, the fh acts as an N,O-bidentate ligand in a centrosymmetric [M(fh)₂(H₂O)₂]²⁺ cation, with charge balance supplied by nitrate counter ions. The packing for the two compounds are quite different: in 1, chains of [Zn(fh)₂(H₂O)₂]²⁺ units are seen in the triclinic unit cell, whereas in the monoclinic structure of 2, sheets of cations occur. This might arise because the conformations of the five-membered chelate rings for the ligands are slightly different, with that for 2 showing a greater degree of puckering.     

Synthesis,structure of a coordination polymer: {Na2[Zn(C2O4)1.5H2PO4] · 2H2O}n

A phosphatooxalate compound {Na₂[Zn(C₂O₄)_1.5H₂PO₄] · 2H₂O}_n 1 was synthesized under hydrothermal condition and characterized by single-crystal X-ray diffraction, IR spectroscopy, thermal gravimetric analysis (TGA) and fluorescent spectroscopy. X-ray single-crystal analysis revealed that its structure was a new mixed inorganic–organic ligand supramolecular framework building up through multilayer assembly.     

Syndiospecific styrene polymerization by (tert-BuC5H4)TiCl2(O-2,6-iPr2C6H3) – borate catalyst system

(^tBuC₅H₄)TiCl₂(O-2,6-ⁱPr₂C₆H₃) (2) exhibited relatively high catalytic activity for syndiospecific polymerization of styrene at 25 °C if both [PhMe₂NH]B(C₆F₅)₄ and a mixture of AlⁱBu₃/Al(n-C₈H₁₇)₃ were used as the cocatalyst. Effects of both organoaluminum and organoboron compounds were explored, and the effect of cocatalyst was different from that observed in 1-hexene polymerization catalyzed by Cp*TiCl₂(O-2,6-ⁱPr₂C₆H₃) (1). Resultant syndiotactic polystyrene possessed narrow molecular weight distribution under the optimized conditions, and the M_w values were unchanged during the time course.     

Synthesis,crystal structure,and thermal stability of a novel 3D cadmium carboxyphosphonate containing left-hand helical chains Cd3Cl2[(O3PCH2–N(H)C5H9–COO)2(H2O)2] · 4H2O

A novel 3D cadmium carboxyphosphonate containing left-hand helical chains, Cd₃Cl₂[(O₃PCH₂–N(H)C₅H₉–COO)₂(H₂O)₂] · 4H₂O 1 has been synthesized by hydrothermal reaction at 120 °C and structurally characterized by single-crystal X-ray diffraction as well as with infrared spectroscopy, elemental analysis and thermogravimetric analysis. In compound 1, the hexanuclear clusters based on Cd(1)O₄Cl₂, Cd(2)O₄Cl₂, Cd(3)O₆ and CPO₃ polyhedra are interconnected through carboxyphosphonate ligands to form a 3D open-framework structure with channel system. The result of connections in this manner is the formation of 20- and 30-atom rings that are parallel to one another and run in the a-axis direction. It is interesting that a type of left-hand helical chain is formed by HL^2? ligands bridging Cd₃ ions running along the b-axis.     

Theoretical investigation of mixed-ligand lanthanocene complexes, (η5-C5H5)2LnX · OC4H8 (Ln=La,Gd, Lu; X=F,Cl, Br,I)

For the first time, density functional theory (DFT) calculation was performed on the titled complexes and the calculated geometries are in good agreement with the available experimental data. The decrease in the bond distances (Ln–X) as well as the increase in the Hirshfeld charges and the chemical hardness from La to Lu indicates an increase in ionic character on going from La to Lu. The lanthanide contraction and ionic character of metal–ligand bond are found to follow the order: Ln–X > Ln–Cp > Ln–O.     

超分子化合物[(C6H6N2O)2Co·2H2O]·2NO3的合成和晶体结构

合成了一个钴配合物[(C6H6N2O)2Co.2H2O].2NO3。该化合物属单斜晶系,P2(1)/n空间群,其化学式为:C12H16CoN6O10,Mr=463.24;晶胞参数:a=0.69527(10)nm,b=1.12250(15)nm,c=1.20352(17)nm,β=97.740(2)°,V=0.9307(2)(nm)3,Z=2,Dc=1.653 mg/m3,F(000)=474,μ=0.989 mm-1,最终偏离因子R1=0.0301,wR2=0.0791。配合物基本单元中含有一个Co(Ⅱ)离子、两分子吡啶酰胺、两分子配位水和两分子硝酸根离子。Co2 离子为六配位的畸变的八面体构型。另外,配合物中存在着丰富的氢键,这些分子间氢键相互加强了相邻单元间的结合,使晶体呈现三维网络超分子结构。     

Organic–inorganic hybrid oxides: Structure and magnetic properties of [{Cu(terpy)}2Mo6O17(H2O)(O3PCH2NH2CH2PO3)2] · H2O,a bimetallic oxide constructed from novel {Mo6O17(H2O)(O3PCH2NH2CH2PO3)2}4− clusters

The hydrothermal reaction of MoO₃, CuSO₄ · 5H₂O, 2,2′:6′:2″-terpyridine (terpy) and bis-N,N-(methylphosphonic acid) amine (H₂O₃PCH₂NHCH₂PO₃H₂) provided blue crystals of the bimetallic oxide [{Cu(terpy)}₂Mo₆O₁₇(H₂O)(O₃PCH₂NH₂CH₂PO₃)₂] · H₂O (1 · H₂O). The three-dimensional structure of 1 is constructed from {Mo₆O₁₇(H₂O)(O₃PCH₂NH₂CH₂PO₃)₂}⁴⁻ clusters linked through {Cu(terpy)}²⁺ subunits. The cluster consists of three pairs of edge-sharing {MoO₆} octahedra linked through corner-sharing interactions into a {Mo₆O₆} ring. One phosphonate ligand spans the diameter of the ring, bridging four molybdenum sites and leaving at a pendant {PO} group at each terminus. The second diphosphonate ligand exploits one {–PO₃} unit to cap the hexamolybdate ring and bridge all six molybdenum sites while the second {–PO₃} terminus bridges two molybdenum sites, leaving a pendant {PO} unit. Crystal data: C₃₄H₄₅Cu₂Mo₆N₈O₃₅P₄: monoclinic, P2₁/n, a = 11.9431(7) Å, b = 17.382(1) Å, c = 27.524(2) Å, β = 90.429(1)°, V = 5713.7(6) Å³, Z = 4, D_calc = 2.270 g cm⁻³, R₁ = 0.0466.     

A novel uranyl complex UO2(tci)(C3H5N2) · H2O: Synthesis,crystal structure and characterization

Reaction of uranium oxynitrate hexahydrate with tris(2-carboxyethyl)isocyanurate (tciH₃) in acidic aqueous solution (pH ～4–5) yields the compound UO₂(tci)(C₃H₅N₂) · H₂O. X-ray diffraction shows that the uranyl ion is in a hexagonal bipyramid structure. Uranium ion in the complex is found to be ligated with three chelating COO^? groups at the equatorial plane, two oxygen atoms linking to uranium atom formed the vertical axis. The complex has the layered topology structure in the space. The thermal analysis verifies the component and the structure of the complex.     

(NH4)2C2O4·H2O和NH4HC2O4·0.5H2O 单晶的培养研究

利用六次甲基四胺缓慢水解产生的NH3和草酸反应,扩散法培养出(NH4)2C2O4·H2O和NH4HC2O4·0.5H2O两种单晶.