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1.
Abstract

The epoxidation of allylic alcohols with H2O2 catalyzed by a new Mo-species, [PMo12O40]3?[C5H5N+(CH2)15CH3]3 (MPCP), prepared from 12-molybdatophosphoric acid (H3PMo12O40) and cetylpyridinium chloride [C5H5N+(CH2)15CH3 · Cl?], has recently rep0rted.) The high regioselectivity for the epoxidation by this MPCP-H2O2 system was comparable to that of Sharpless method using t-BuOOH as oxidant.  相似文献   

2.
Wang  Shutao  Wang  Enbo  Hou  Yu  Li  Yangguang  Wang  Li  Yuan  Mei  Hu  Changwen 《Transition Metal Chemistry》2003,28(6):616-620
A novel organic/inorganic hybrid molybdenum phosphate, [NH3(CH2CH2)2NH3]3[NH3(CH2CH2)2NH2]Na5-[Mo6O12(OH)3(PO4)(HPO4)3]2·4H2O (1), involving molybdenum presented in V oxidation, has been hydrothermally prepared and characterized by elemental analysis, i.r., u.v.–vis., x.p.s., t.g. and single crystal X-ray diffraction. The structure of the title compound (1) may be considered to consist of two [Mo6O12(OH)3(PO4)(HPO4)3] units bonded together with NaO6 octahedra, forming dimers. Further, these dimers connect with each other through four Na+ cations as bridges, giving rise to novel one-dimensional chain-like skeleton. Piperazines exist among inorganic chains acting as charge balancing cations.  相似文献   

3.
Alkylammonium Hexachlorometallates. I. Crystallization Properties and Crystal Structure of Diethylenetriammonium Hexachlororhodate, [H3N(CH2)2NH2(CH2)2NH3][RhCl6] The reaction of RhCl3 · 3H2O with diethylenetriamine in 12 m hydrochloric acid yielded diethylenetriammonium hexachlororhodate [H3N(CH2)2NH2(CH2)2NH3][RhCl6] ( 1 ). Dark red single crystals of the compound were grown under hydrothermal conditions at a temperature interval of 180°C to 125°C in closed glass ampoules over several weeks (space group C2/c, a = 30.956(4) Å, b = 7.371(2) Å, c = 12.9736(15) Å, β = 113.787(11)°, Z = 8, 2385 reflections with I > 0, wR2(obs.) = 0.0279, R1(I > 2σ(I)) = 0.0271). The crystal structure is determined by a complex framework of hydrogen bonds between the hexachlororhodate anions and the diethylenetriammonium cations.  相似文献   

4.
Synthesis and Crystal Structures of [P(C6H5)4][1-(NH3)B10H9] and Cs[(NH3)B12H11] · 2CH3OH The reduction of [1-(NO2)B10H9]2? with aluminum in alkaline solution yields [1-(NH3)B10H9]? and by treatment of [B12H12]2? with hydroxylamine-O-sulfonic acid [(NH3)B12H11]? is formed. The crystal structures of [P(C6H5)4][1-(NH3)B10H9] (triclinic, space group P1 , a = 7.491(2), b = 13.341(2), c = 14.235(1) Å, α = 68.127(9), β = 81.85(2), γ = 86.860(3)°, Z = 2) and Cs[(NH3)B12H11] · 2CH3OH (monoclinic, space group P21/n, a = 14.570(2), b = 7.796(1), c = 15.076(2) Å, β = 111.801(8)°, Z = 4) reveal for both compounds the bonding of an ammine substituent to the cluster anion.  相似文献   

5.
(CH3NH3)4YbCl7 has been synthesized from a solution of CH3NH3Cl and YbCl3 in a mixture of ethnole/acetonitrile. The structure was solved from 1464 single crystal data by Patterson methods and refined to a final Rw = 0.035 space group P2, a = 9.972(6) Å, b = 7.605(5) Å, c = 12.866(6) Å, β = 90.53(4)°. The structure consists of alternating [YbCl6]3? octahedra and of tetrahedrally arranged [(CH3NH3)4Cl]3+ units. Raman spectra display a splitting of frequencies related to the CH3NH3+ group in agreement with the structure determination. The magnetic susceptibility shows a remarkable deviation from a Curie-Weiss law below 170 K which may be explained by crystal field effects of Yb3+.  相似文献   

6.
The reaction of ammonium heptamolybdate with hydrazine sulfate in an aqueous solution of glycine at room temperature yielded colorless crystals of (NH4)4[(NH3CH2CO)2(Mo8O28)] · 2 H2O. The crystal is monoclinic, space group C2/c (no. 15), a = 17.234 Å, b = 10.6892 Å, c = 18.598 Å, β = 108.280°, V = 3253.2 Å3, Z = 4. The crystal structure contains ammonium cations and isolated octamolybdate(4–) anions, [(NH3CH2CO)2(Mo8O28)]4–, with two zwitterionic glycine molecules as ligands.  相似文献   

7.
Trans-[Cr(NH3)4(H2O)Cl]Cl2 (A) crystallizes in the monoclinic space group P21/m (No. 11) with a = 6.556(1), b = 10.630(5), c = 6.729(2) Å and β = 96.15(3)°. Trans-[Cr(NH3)4Cl2]I (B) has monoclinic C2/m (No. 12) space group and a = 9.877(2), b = 8.497(2), c = 6.047(2) Å and β = 108.98(2)°. Both unit cells contain two formula units. Cr? Cl, Cr? O(H2O) and three independent Cr? N(NH3) distances for A are 2.98(1), 2.023(2), 2.067(2), 2.086(3) and 2.064(3) °. Cr? Cl and Cr? N(NH3) bonds in B are 2.325(1) and 2.071(2) °. All octahedral angles are close to 90 and 180°. Both structures were refined to very low R values. Water molecule from trans-[Cr(NH3)4(H2O)Cl]2+ is hydrogen bonded to both ionic chlorides. Cation and two anions form the motive which repeats itself in the crystal. Cations and anions of the second structure are distributed in layers. Each cation and anion have coordination number eight.  相似文献   

8.
Crystal Structures of Acid Hydrates and Oxonium Salts. XX. Oxonium Tetrafluoroborates H3OBF4, [H5O2]BF4, and [H(CH3OH)2]BF4 The crystal structures of three oxonium tetrafluoroborates were determined. H3OBF4, oxonium tetrafluoroborate proper, is triclinic with space group P1 , Z = 2 and the unit cell dimensions a = 4.758, b = 6.047, c = 6.352 Å and α = 80.40, β = 79.48, γ = 88.25° at ?26°C. Cations H3O+ and anions BF4? are linked by hydrogen bonds O? H…?F into ribbons of condensed rings. In [H5O2]BF4 (diaquohydrogen tetrafluoroborate, monoclinic, P21/c, Z = 4, a = 6.584, b = 9.725, c = 7.084 Å, β = 95.15° at ?100°C) the hydrogen bond in the cation H5O2+ is 2.412 Å short, asymmetric and approximately centered and the linking of cations and anions three-dimensional. In [H(CH3OH)2]BF4 (Bis(methanol)hydrogen tetrafluoroborate, monoclinic, P21/c, Z = 4, a = 5.197, b = 14.458, c = 9.318 Å, β = 94.61° at ?50°C) the cation [H(CH3OH)2]+ is characterized for the first time in a crystal structure with an again very short (2.394 Å), asymmetric and effectively centered hydrogen bond. By further hydrogen bonds cations and anions form only dimers of the formula unit of centrosymmetric cyclic structure.  相似文献   

9.
Preparation and Crystal Structure of (CH3NH3)8[NdCl6][NdCl4(H20)2]2Cl3 (CH3NH3)8[NdCl6][NdCl4 (H2O)2]2Cl3 is for the first time prepared and investigated by X-ray, single crystal work. It crystallizes in the monoclinic system (space group C2/m, Z = 2) with a = 9.358(5), b = 17.424(9), c = 15.360(8) Å, β = 108.30(4)°. The structure contains besides isolated Cl? ions distorted [NdCl6]3? octahedra and [NdCl4(H2O)2]? chains.  相似文献   

10.
A new microporous iron (III) phosphate, [H3N(CH2)4NH3]3[Fe8(HPO4)12(PO4)2(H2O)6], has been prepared using low temperature hydrothermal methods and characterized by single-crystal X-ray diffraction, EDAX, infrared spectroscopy, thermogravimetric analysis and bond valence sums. The title compound crystallizes as light pink hexagonal-shaped tabs in the centrosymmetric hexagonal space group 3¯ (No.147) with a = b = 13.495(2) Å, c = 9.396(2) Å, V = 1481.9(4) Å3 and Z = 4 with R/Rw = 0.044/0.048. The compound exhibits a complicated three-dimensional microporous structure with quaternary ammonium ions acting as a template for the framework. It is similar to previously reported [HN(CH2CH2)3NH]3[Fe8(HPO4)12(PO4)2(H2O)6].  相似文献   

11.
Anhydrous Lanthanum Acetate, La(CH3COO)3, and its Precursor, ·NH4)3[La(CH3COO)6] · 1/2 H2O: Synthesis, Structures, Thermal Behaviour Single crystals of (NH4)3[La(CH3COO)6] · ½ H2O are obtained by refluxing La2O3in (CH3COO)3 · 1.5 H2O with an excess of NH4CH3COO in methanol. The crystal structure (trigonal, R3 , Z = 6, a = 1 365.0(3) pm, c = 2 360(1) pm, R = 0.088, Rw = 0.061 exhibits the coordination number of nine for La3+, which is surrounded by three chelating-type bidentate and three unidentate acetate groups. Characteristic are monomeric units of [La(CH3COO)6]3? which are connected to a three-dimensional network by hydrogen bonds with the NH ions. Thermal decomposition consists of four steps with La(CH3COO)3, La2(CO3)3 and La2O2CO3 as intermediates and La2O3 as the final Product. Single crystals of La(CH3COO)3 are obtained from La2O3 in a melt of NH4CH3COO (molar ratio 1:12) in a sealed glass ampoule. The crystal structure (trigonal, R3 , Z = 18, a = 2 203.0(5) pm; c = 987.1(3) pm, R = 0.027, Rw = 0.023) shows the coordination number of ten for La3+. These are three-dimensionally connected by oxygen atoms of the acetate groups with two tetradentate double-bridging and one Z,Z-type-bridging bidentate acetate group.  相似文献   

12.
A charge-transfer compound [(CH3)3CNH3]3[PMo12O40] · 2H2O was synthesized and characterized by IR, UV, ESR, diffusion reflectance electronic spectrum, cyclic voltammogram and X-ray crystallography. Oxygen atoms of the polyoxometalate anion, N atoms of organic substrates (CH3)3CNH2 and O atoms of water molecules are involved in hydrogen bonding. The solid reflectance electronic spectra and IR data indicate the presence of interaction between the [PMo12O40]3− and the organic substrates in the solid state. Photosensitivity to ultraviolet light was assessed for the compound, showing that charge-transfer resulted from oxidation of the organic substrates and the reduction of the heteropolyanion.  相似文献   

13.
The structure of two trinuclear iron acetates [Fe3O(CH3COO)6(H2O)3]Cl· 6H2O (I) and [Fe3O(CH3COO)6(H2O)3][FeCl4] · 2CH3COOH (II) was determined by X-ray diffraction analysis. Crystals I and II are ionic and belong to the orthorhombic system with parameters a = 13.704(3), b = 23.332(5), c = 9.167(2) Å, R = 0.0355, space goup P21212 for I and a = 10.145(4), b = 15.323(6), c = 22.999(8) Å, R = 0.0752, space group Pbc21 for II. The complex cation [Fe3O(CH3COO)6(H2O)3]+ has a μ3-O-bridged structure typical for trinuclear iron (III) compounds. As shown by Mössbauer spectroscopy, the iron(III) ions are in the high-spin state. In trinuclear cations, antiferromagnetic exchange interaction takes place between the Fe(III) ions with the exchange parameter J = -26.69 cm?1 for II (Heisenberg-Dirac-Van Vleck model for D3h, symmetry).  相似文献   

14.

A novel hybrid compound, [(CH3)2NH2]6[Cu(DMF)4(GeW12O40 4-)2] [sdot] 2DMF, has been synthesized from H4GeW12O40 [sdot] n H2O, CuCl2 and N, N -dimethylformamide (DMF) in aqueous solution and characterized by elemental analysis, UV and IR spectra. Single crystal X-ray structure analysis shows that the crystal consists of a α-Keggin heteropolyanion-supported anion [Cu(DMF)4(GeW12O40 4-)2], two free N, N-dimethylformamide molecules, six protonated dimethylamine (DMA) molecules, and that the coordinating atoms of DMF are the oxygen atoms of C=O group. Thermal analysis indicates that the thermal stability of the GeW12O40 4- anion in the title compound is stronger than that in acid.  相似文献   

15.
A hydrothermal reaction of a mixture of ZnO, HCl, ethylenediphosphonic acid, ethylenediamine, acetic acid in a water, THF mixture gave rise to a new three‐dimensional zinc ethylenediphosphonate, [NH3(CH2)2NH3][Zn3{O3P(CH2)2}4], I . The structure, determined by single crystal X‐ray diffraction, (monoclinic, space group = C2/c, a = 16.9948(14), b = 6.7383(6), c = 16.8886(14)Å, β = 1113.568(1)°, V = 1772.7(3)Å3, Z = 4, R1 = 0.0227, wR2 = 0.0601), consists of a network of strictly alternating ZnO4 and PO3C tetrahedral units linked through their vertices forming the three‐dimensional structure. The amine molecules occupy the middle of the 8‐membered channels and interact with the framework through the hydrogen bonds. Unlike other zinc diphosphonates, I appear to have close similarity to zinc phosphate structures reported in the literature. To our knowledge, this is the first three‐dimensional zinc diphosphonate prepared in the presence of an organic amine molecule.  相似文献   

16.
K3[DyIII(nta)2(H2O)]·5H2O and (NH4)3[DyIII(nta)2] have been synthesized in aqueous solution and characterized by IR, elemental analysis and single-crystal X-ray diffraction techniques. In K3[DyIII(nta)2(H2O)]·5H2O the DyIII ion is nine coordinated yielding a tricapped trigonal prismatic conformation, and its crystal belongs to monoclinic system and C2/c space group. The crystal data are as follows: a = 15.373(5) Å, b = 12.896(4) Å, c = 26.202(9) Å; β = 96.122(5)°, V = 5165(3) Å3, Z = 8, D c = 1.965 g·cm?3, μ = 3.458 mm?1, F(000) = 3016, R 1 = 0.0452 and wR 2 = 0.1025 for 4550 observed reflections with I ≥ 2σ(I). In (NH4)3[DyIII(nta)2] the DyIII ion is eight coordinated yielding a usual dicapped trigonal anti-prismatic conformation, and its crystal belongs to monoclinic system and C2/c space group. The crystal data are as follows: a = 13.736(3) Å, b = 7.9389(16) Å, c = 18.781(4) Å; β = 104.099(3)°, V = 1986.3(7) Å3, Z = 2, D c = 1.983 g·cm?3, μ = 3.834 mm?1, F(000) = 1172, R 1 = 0.0208 and wR 2 = 0.0500 for 2022 observed reflections with I ≥ 2σ(I). The results indicate that the difference in counter ion also influences coordination numbers and structures of rare earth metal complexes with aminopolycarboxylic acid ligands.  相似文献   

17.
The crystal structures have been determined of CH3NH3HgCl3, (CH3NH3)2HgCl4, and CH3NH3Hg2Cl5. In (CH3NH3)2HgCl4 the HgII atom is tetrahedrally coordinated by four Cl atoms with Hg? Cl bond lengths of 2.464 to 2.478 Å. In the other two compounds the HgII atom is involved in two short covalent Hg? Cl bonds, forming a pseudo HgCl2 molecule and two much longer bridging Hg? Cl bonds. The methylammonium groups are connected by hydrogen bonds to the chlorine atoms. The nature of the hydrogen bonding scheme probably causes disorder of the methylammonium groups.  相似文献   

18.
《Solid State Sciences》1999,1(6):321-329
Chemical preparation, crystal structure and infrared absorption spectra are given for a new organic cation dihydrogendiphosphate. The new synthesized compound [C6H5(CH2)2NH3]2H2P2O7; crystallized in the monoclinic system (P21/c space group) with Z = 4 and with the following unit-cell dimensions: a = 19.006(3); b = 10.718(2), c = 10.996(3) Å and β = 98.99(2) °. Its crystal structure was determined and refined down to R = 0,056 by using 3278 independent reflections. As in all atomic arrangements including acidic diphosphate groups; we can observe the formation of an infinite network of anions connected by strong H-bonds.  相似文献   

19.
The Crystal Structures of (NH4)2[ReCl6], [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN and [ReCl4(18)(Crown-6)] Brown single crystals of (NH4)2[ReCl6] are formed by the reaction of NH4Cl with ReCl5 in a suspension of diethylether. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN crystallizes as brown crystal plates from a solution of ReCl5 in acetonitrile. Lustrous green single crystals of [ReCl4(18-crown-6)] are obtained by the reaction of 18-crown-6 with ReCl5 in a dichloromethane suspension. All rhenium compounds are characterized by IR spectroscopy and by crystal structure determinations. (NH4)2[ReCl6]: Space group Fm3 m, Z = 4, 75 observed unique reflections, R = 0.01. Lattice constant at ?70°C: a = 989.0(1) pm. The compound crystallizes in the (NH4)2[PtCl6] type, the Re? Cl distance is 235.5(1) pm. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN: Space group P1, Z = 1, 2459 observed unique reflections, R = 0.12. Lattice dimensions at ?60°C: a = 859.0(1), b = 974.2(7), c = 1287.3(7) pm, α = 102.69(5)°, b? = 105.24(7)°, γ = 102.25(8)°. The structure consists of two symmetry-independent [ReCl2(CH3CN)4]+ ions with trans chlorine atoms, [ReCl6]2? ions, and included acetonitrile molecules. In the cations the Re? Cl bond lengths are 233 pm in average, in the anion they are 235 pm in average. [ReCl4(18-crown-6)]: Space group P21/n, Z = 4, 3 633 observed unique reflections, R = 0.06. Lattice dimensions at ?70°C: a = 1040.2(4), b = 1794.7(5), c = 1090.0(5) pm, b? = 108.91(4)°. The compound forms a molecular structure, in which the rhenium atom is octahedrally coordinated by the four chlorine atoms and by two oxygen atoms of the crown ether molecule.  相似文献   

20.
The crystalline structure of a new compound Rh(III) of (NH4)2[Rh(NO2)3(NH3)(μ-OH)]2 composition has been determined. The crystallographic characteristics are H16N10O14Rh2: a = 6.3963(2) Å, b = 9.3701(4) Å, c = 13.6646(5) Å, β = 102.266(1)°, V = 800.28(5) Å3, Z = 2, d calc = 2.432 g/cm3. The distance Rh...Rh in the dimer is 3.200 Å. Original Russian Text Copyright ? 2006 by S. P. Khranenko, I. A. Baidina, and S. A. Gromilov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 47, No. 2, pp. 380–384, March–April, 2006.  相似文献   

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