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The reactions of ten metastable immonium ions of general structure R1R2C?NH+C4H9 (R1 = H, R2 = CH3, C2H5; R1 = R2 = CH3) are reported and discussed. Elimination of C4H8 is usually the dominant fragmentation pathway. This process gives rise to a Gaussian metastable peak; it is interpreted in terms of a mechanism involving ion-neutral complexes containing incipient butyl) cations. Metastable immonium ions ontaining an isobutyl group are unique in undergoing a minor amount of imine (R1R2C?NH) loss. This decomposition route, which also produces a Gaussian metastable peak, decreases in importance as the basicity of the imine increases. The correlation between imine loss and the presence of an isobutyl group is rationalized by the rearrangement of the appropriate ion-neutral complexes in which there are isobutyl cations to the isomeric complexes containing the thermodynamically more stable tert-butyl cations. A sizeable amount of a third reaction, expulsion of C3H6, is observed for metastable n-C4H9 +NH?CR1R2 ions; in contrast to C4H8 and R1R2C?NH loss, C3H6 elimination occurs with a large kinetic energy release (40–48 kJ mol?1) and is evidenced by a dish-topped metastable peak. This process is explained using a two-step mechanism involving a 1,5-hydride shift, followed by cleavage of the resultant secondary open-chain cations, CH3CH+ CH2CH2NHCHR1R2.  相似文献   

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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   

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鲁晓明  宋富根  王波  李丽 《无机化学学报》2005,21(11):1687-1690
Cis-dioxo-catecholatotungsten(Ⅴ) complex (NH2CH2CH2NH3)4[WO2(OC6H4O)2]2(NH3CH2CH2NH3)·H2O (1) was synthesized at room temperature by the reaction of tetrabutyl ammonium decatungstate with catechol in the mixed solvent of CH3OH, CH3CN and NH2CH2CH2NH2. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21/c,a=0.712 8(3) nm, b=3.082 3(11) nm, c=0.982 8(4) nm, β=102.639(6)°, V=2.106 8(14) nm3, Z=2, R1=0.062 8, wR2=0.183 7. Compared the complex with its analogous complexes (NH2CH2CH2NH3)3[MoO2(OC6H4O)2], it is found that the coordination structure of W have no changes in the processing of electron transfer of tungsten-containing enzymes from the result of the similarity of the EPR spectra of the complexes and flavoenzyme from milk. CCDC: 272937.  相似文献   

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Cis-dioxo-tungsten(Ⅵ) complex, (NH2CH2CH2NH2)[(NH2CH2CH2NH3)2WO2(NHC6H4NH)2]2·H2O is synthesized at room temperature by the reaction of sodium tungstate with o-phenylenediamine. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P21/ c, a=0.712 8(2) nm, b=3.081 1(10) nm, c=0.981 9(3) nm, β=102.615(4)°, V=2.104 4(11) nm3, Z=2, μ=55.26 cm-1, F(000)=1 176. Compared the complex with its analogous biomimetic complexes of the cofactor of molybdoenzymes and tungstoenzymses, it is found that the variance of the coordination atoms and the metal ions center have no influence on the coordination feature, and exhibits distored octahedral coordination with cis-dioxo o-phenylenediamine. CCDC: 252834.  相似文献   

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The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 and [Ni(NH3)6]Cl2 Crystals of yellow [V(NH3)6]I2 and green [Cr(NH3)6]I2 were obtained by the reaction of VI2 and CrI2 with liquid ammonia at room temperature. Colourless crystals of [Mn(NH3)6]Cl2 were obtained from Mn and NH4Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH3)6]Cl2 and [Fe(NH3)6]Br2 were obtained by the reaction of FeCl2 and FeBr2 with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH3)6]Br2 were obtained from [Co2(NH2)3(NH3)6]Br3. Purple crystals of [Ni(NH3)6]Cl2 were obtained by the reaction of NiCl2 · 6H2O and NH4Cl with aqueous NH3 solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K2[PtCl6] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.  相似文献   

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In hexakis(m‐toluidinium) cyclo­hexaphosphate, 6C7H10N+·­P6O186?, the atomic arrangement is typical of a layer structure. Layers including the centrosymmetric P6O18 ring anions develop around the (100) planes at x = . The hydrogen‐bond distribution is described.  相似文献   

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Structure and Properties of Double Halogenides of Substituted Ammonium and Mercury(II). VI. Crystal Structure of (CH3NH3)2HgBr4 and (CH3NH3)2HgI4 The compounds (CH3NH3)2HgBr4 and (CH3NH3)2HgI4 were prepared from stoichiometric mixtures of the methylammonium halogenides and the mercury(II) halogenides in methanol by evaporation. X-ray structure determination revealed for (CH3NH3)2HgBr4 monoclinic symmetry, space group P21/c and orthorhombic symmetry, space group Pbca for (CH3NH3)2HgI4. Both compounds are built from isolated, slightly deformed tetrahedra. The Hg? Br distances range from 2.586(3) Å to 2.598(2) Å, the Br? Hg? Br angles from 105.36(8)° to 112.26(8)°. The observed distances in the HgI4 tetrahedra are in the range 2.751(1) and 2.803(1) Å, the I? Hg? I angles between 106.25(3)° and 115.68(4)°. The tetrahedra are linked together by hydrogen bonds between the methylammonium group and the halogen atoms.  相似文献   

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1 INTRODUCTION During the past decade, a series of organic-inor- ganic hybrid compounds based on metal halide units have been prepared and studied[1]. The combination of organic and inorganic components at the mole- cular level affords us the opportunity to design new hybrid materials and modulate the properties of components[2]. As a result, some interesting proper- ties, such as non-linear optical[3], interesting magne- tic[4], efficient luminescence[2], ideal thermal and mechanical sta…  相似文献   

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The room-temperature syntheses and single-crystal structures of C(4)N(2)H(12).NH(4)Cl(3).H(2)O and C(6)N(2)H(14).NH(4)Cl(3) are reported. These novel molecular perovskites contain vertex-sharing octahedral (NH(4))Cl(6) arrays which replicate the octahedral packing in the cubic (SrTiO(3)) and 2-H hexagonal (BaNiO(3)) perovskite structures, respectively. The structures are completed by doubly protonated organic cations and, for the cubic phase, water molecules. Crystal data: C(4)N(2)H(12).NH(4)Cl(3).H(2)O, M(r) = 230.56, orthorhombic, Pbcm (No. 57), a = 6.5279(13) A, b = 12.935(3) A, c = 12.849(3) A, V = 1085.0(4) A(3), Z = 4; C(6)N(2)H(14).NH(4)Cl(3), M(r) = 238.59, trigonal, Pthremacr;c1 (No. 165), a = 16.1616(2) A, c = 22.3496(4) A, V = 5055.5(2) A(3), Z = 18.  相似文献   

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Normal Coordinate Analysis of (CH3)2SO2, (CH3)2SO(NH), and (CH3)2S(NH)2 using the Method of Stepwise Coupling The qualitative assignment of the vibrational spectra of (CH3)2SO2 ( 1 ), (CH3)2SO(NH) ( 2 a ), and (CH3)2S(NH)2 ( 3 a ) and of the C and N deuterated derivatives of 2 a and 3 a is used in a normal coordinate analysis by the method of stepwise coupling. The force constants and the energy distributions are calculated in symmetry coordinates using a generalized valence force field.  相似文献   

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两种镍的配合物[Ni(NH2CH2CH2CH2NH2)3]Cl2 (1)和[Ni(C6H4N2H4)2Cl2] (2)已经被合成并且通过红外和单晶X射线衍射分析对其进行了表征。在配合物1中,镍原子处于手性假八面体[NiN6]的几何构型中,它与三个1,3-丙二胺分子形成了三个六元环。在配合物2中,镍原子除了与两个o-苯二胺分子通过四个Ni-N键形成两个五元环外,它还与两个Cl原子配位形成了反式Ni-Cl2,这不同于以往报道过的镍的二胺配合物。这两个镍的配合物被MAO, MMAO或Et2AlCl活化后,对乙烯的二聚合或三聚合显示了很好的催化活性[对于配合物2,催化活性达到3.59×106 g mol-1 (Ni) h-1]。  相似文献   

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A new cobalt(II) carboxylate-phosphonate, namely, Co[HO2C(CH2)3NH(CH2PO3H)2]2, with a layered architecture has been synthesized by hydrothermal reactions. The Co(II) ion in the title compound is octahedrally coordinated by six phosphonate oxygen atoms from four carboxylate phosphonate ligands. Neighboring CoO6 octahedra are interconnected by phosphonate groups into a 2D layer with a 4,4-net topology. Adjacent layers are further cross-linked via hydrogen bonds between the noncoordinate carboxylate groups and noncoordinate phosphonate oxygens. The ac and dc magnetic susceptibility and magnetization measurements indicate that Co[HO2C(CH2) 3NH(CH2PO3H)2]2 is a canted antiferromagnet with T(c) = 8.75 K.  相似文献   

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