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1.
The fluorination reactions of (C6F5)3E (E = As, Sb) with elemental flourine yield (C6F5)3EF2 in high yields. From the reactions of (C6F5)3EF2 with CsF the new salts Cs[(C6F5)3EF3] are obtained. (C6F5)2SeF2 and C6F5TeF3 are formed for the first time by reacting (C6F5)2SeF and (C6F5)2TeF2 with elemental flourine and XeF2, respectively. (C6F5)2SeF2 rapidly reacts with glass, and the new compound (C6F5)2SeO is isolated. The preparations, properties and 19F NMR spectra of the new compounds are described.  相似文献   

2.
A recent crystallographic study has shown that, in the solid state, P(C(6)H(5))(4)N(3) and As(C(6)H(5))(4)N(3) have ionic [M(C(6)H(5))(4)](+)N(3)(-)-type structures, whereas Sb(C(6)H(5))(4)N(3) exists as a pentacoordinated covalent solid. Using the results from density functional theory, lattice energy (VBT) calculations, sublimation energy estimates, and Born-Fajans-Haber cycles, it is shown that the maximum coordination numbers of the central atom M, the lattice energies of the ionic solids, and the sublimation energies of the covalent solids have no or little influence on the nature of the solids. Unexpectedly, the main factor determining whether the covalent or ionic structures are energetically favored is the first ionization potential of [M(C(6)H(5))(4)]. The calculations show that at ambient temperature the ionic structure is favored for P(C(6)H(5))(4)N(3) and the covalent structures are favored for Sb(C(6)H(5))(4)N(3) and Bi(C(6)H(5))(4)N(3), while As(C(6)H(5))(4)N(3) presents a borderline case.  相似文献   

3.
Threshold photoelectron photoion coincidence has been used to prepare selected internal energy distributions of nitrosobenzene ions [C(6)H(5)NO(+)]. Dissociation to C(6)H(5)(+) + NO products was measured over a range of internal energies and rate constants from 10(3) to 10(7) s(-1) and fitted with the statistical theory of unimolecular decay. A 0 K dissociative photoionization onset energy of 10.607 ± 0.020 eV was derived by using the simplified statistical adiabatic channel model. The thermochemical network of Active Thermochemical Tables (ATcT) was expanded to include phenyl and phenylium, as well as nitrosobenzene. The current ATcT heats of formation of these three species at 0 K (298.15 K) are 350.6 (337.3) ± 0.6, 1148.7 (1136.8) ± 1.0, and 215.6 (198.6) ± 1.5 kJ mol(-1), respectively. The resulting adiabatic ionization energy of phenyl is 8.272 ± 0.010 eV. The new ATcT thermochemistry for phenyl entails a 0 K (298.15 K) C-H bond dissociation enthalpy of benzene of 465.9 (472.1) ± 0.6 kJ mol(-1). Several related thermochemical quantities from ATcT, including the current enthalpies of formation of benzene, monohalobenzenes, and their ions, as well as interim ATcT values for the constituent atoms, are also given.  相似文献   

4.
以三聚氰胺和硼酸为原料在水溶液中反应合成出了一种新的BCN化合物先驱体C3N6H6(H3BO3)2。XRD表征结果表明三聚氰胺和硼酸的最佳配比为1∶3(物质的量比)。用单晶X-射线衍射分析法测定了该化合物的晶体结构。该化合物属单斜晶系,空间群为P21/C,晶胞参数为a=0.3597(7)nm,b=2.0105(4)nm,c=1.4112(3)nm,α=90,°β=92.07(3),°γ=90,°V=1.0199(3)nm3,Z=4,D c=1.627g.cm-3,μ(MoKα)=0.144mm-1,F(000)=520。晶体结构经全矩阵最小二乘法修正,最终可靠因子R1=0.0519,wR2=0.1361。该化合物是由C3N6H6分子和H3BO3分子通过氢键加合组装形成的三维超分子结构化合物。  相似文献   

5.
The roe of oxidatively induced homolyhc scission a the C(sp3)-H bonds in the iron phenykychhexadienyl complexes Fe(5-6-PhC6H6)(5-C5H5) (1) depends on the spatial orientation of the Ph substitutent. In the case of the (1 endo +) radical cation this process, resulting in the cationic biphenyl complex (Fe(6 -C6H5C6H5)(5-C5H5)]+ (2 +), is fast and proceeds for several minutes. In the case of the more stable radical cation (1 exo +) the formation of 2+ is slow and takes tens minutes to complete.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1698–1700, July, 1996.  相似文献   

6.
Tris(2,4,6-trimethylphenyl)antimony dihydroxide, Mes3Sb(OH)2, which was prepared by oxidation of Mes3Sb with H2O2, has been shown to react with RSO3H (R = C6H5, CF3) to give the adducts Mes3SbO · HO3SR, the first examples of solid hydrogen-bonded adducts of a triorganoantimony oxide and an acid. The crystal structure of Mes3SbO·HO3SC6H5 has been determined. The three C(mesityl) atoms and the O atom form a distorted tetrahedron around Sb, the distortion by the bulky mesithyl groups being reflected in the CSbC angles (mean: 114.7(3)°) and the CSbO angles: (mean: 103.5(2)°). C6H5SO3H is linked via a short hydrogen bond to O on Sb, with O(1) z.;O(2) = 256(1) pm. The bond length SbO(1) 189.4(5) pm represents the shortest SbO distance ever reported.  相似文献   

7.
李君  张逢星  唐宗薰  史启祯 《化学学报》2001,59(7):1116-1120
Mn(O2CMe)2·4H2O、咪唑、苯甲酸和N(n-Bu)4MnO4在无水乙醇溶剂中反应,制备得到锰的三核μ3-O桥联配位化合物[Mn3O(O2CC6H5)6(C3H4N2)3]·C6H5CO2·0.5H2O.该配位化合物的X射线单晶衍射表明,其属于单斜晶系,空间群P21/C,晶胞参数:a=1.52832(19)nm,b=1.9722(2)nm,c=2.1023(3)nm,β=92.597(3)°,Z=4.变温磁化率(5~280K)研究表明,该配位化合物中3个锰离子在低温下存在弱的反铁磁性耦合,交换积分J=-2.34cm^-1。  相似文献   

8.
黄丹  徐凡  沈琪 《中国稀土学报》2005,23(4):505-508
研究了(C5H5)2NdCl·2LiCl与正丁基锂在THF溶液中的反应, 并从该反应液中分离到了钕的氢化物[Li(DME)3][(C5H5)3Nd(μ-H)Nd(C5H5)3] 1. 化合物1经X射线单晶结构测定表明属单斜晶系, 空间群P21/c, 晶胞参数为a=0.9670(2) nm, b=2.1001(5) nm, c=2.1279(7) nm, β=90.89(2)°, Z=4, V=4.321 (2) nm3, Mr=957.36, Dc=1.47 g·cm-3, F(000)=1936, R=0.094, wR=0.100. 1的晶胞中包含两个独立的晶体分子, 每一分子由阴阳离子对[Li(DME)3]+和[(C5H5)3Nd(μ-H)Nd(C5H5)3]-组成. 钕原子与3个η5-C5H5基团配位, 且两个(C5H5)3Nd经氢桥键相连构成阴离子. Nd1-H和Nd2-H键长均为0.218(1) nm.  相似文献   

9.
The salt Rb[C6H3(COO)2()] · [C6H3(COOH)3] · 2H2O (I) of trimesic acid was synthesized and its thermal stability and conductivity (10–11 ohm–1 cm–1 at 298 K) were measured. Molecular and crystal structures of I were established by X-ray diffraction analysis. Hydrogen bonding system in complex I was detected by IR and Raman spectroscopies. X-ray diffraction data agree with vibration spectroscopy data.  相似文献   

10.
The complex from reaction of neodymium chloride six-hydrate with salicylic acid and 8-hydroxyquinoline, Nd(C7H5O3)2·(C9H6NO), was synthesized and characterized by IR, elemental analysis, molar conductance, and thermogravimatric analysis. The standard molar enthalpies of solution of [NdCl3·6H2O(s)], [2C7H6O3(s)], [C9H7NO(s)] and [Nd(C7H5O3)2·(C9H6NO)(s)] in a mixed solvent of anhydrous ethanol, dimethyl formamide (DMF) and perchloric acid were determined by calorimetry at 298.15 K. Based on Hess’ law, a new chemical cycle was designed, and the enthalpy change of the reaction
((1))
was determined to be Δr H mΘ=117.89±0.37 kJ mol−1. From data in the literature, through Hess’ law, the standard molar enthalpy of formation of Nd(C7H5O3)2·(C9H7NO)(s) was estimated to be Δf H mΘ[Nd(C7H5O3)2·(C9H6NO)(s), 298.15 K]=−2031.80±8.6 kJ mol−1. Project supported by the Natural Sciences Foundation of Hunan Provincial of China (No. 03JJY3019)  相似文献   

11.
Abstract

The structure of triethylammonium diphenoxy-o-phenylenedioxy-1,2-bistrifluoromethylethenylenedioxyphosphoride, a compound with hexacoordinate phosphorus obtained by addition of triethylammonium phenoxide to the pentacoordinate phosphorus precursor, has been determined by x-ray crystallographic methods. The compound crystallizes from ether in space group P21/n of the monoclinic system. There are four formula units, (C22H14O6P)-(NC6H15)+ in the unit cell (Z=4), with one ion-pair constituting the asymmetric unit of the crystal. The cell dimensions are a=10.787(5), b=16.604(6), c=16.668(4) Å; β=102.84°(3); D ctlc=1.415 g cm?3, D meas=1.412 g cm?3 (25°). Data were obtained on a CAD4 automatic diffractometer; 5310 unique non-zero reflections were collected with θ≤ 75° using (θ-2θ) scan, with a scan width of 1.0°. The phosphorus and oxygen atoms were located using the MULTAN program. All other non-hydrogen atoms were found in subsequent iterations of partial-structure phased Fourier maps. The structure was refined by full-matrix least-squares techniques to a final R w value of 7.5% on F based on 4855 independent reflections. The phosphorus atom is hexacoordinate and at the center of a nearly regular octahedron, with the two phenoxy groups cis to each other. The two P–O (exocyclic) bonds are shorter (ave. 1.656(4) Å) than the four P–O (endocyclic) bonds (ave. 1.711(4) Å). The positively charged nitrogen is closer to two of the uncharged oxygen ligands (3.000 and 3.108(6) Å) than to the negatively charged phosphorus (4.063(6) Å) within the formula unit. The changes in molecular parameters when an oxyphosphoride is derived from an oxyphosphorane by addition of a sixth oxy-ligand are discussed.  相似文献   

12.
The complex (η5-C5H5)Cr(CO)3Cp42 H5 has been made and its reactions with σ donor ligands L (L = (MeO)3P and (EtO)3P) and with SO2 studied. The alkyl phosphites give compounds of the composition (η5-C5H5)Cr(CO)2LC2H5, and sulfur dioxide gives the corresponding S-sulfinato (η5-C5H5)Cr(CO)3SO2C2H5.  相似文献   

13.
IR and NMR data showed that the ionic complex Pd2(CHCC6H5)2(C5H7O2)3(BF3)2BF4 isolated in the reaction Pd(Acac)2 + PA + 5BF3OEt2 (Acac is C5H7O2, PA is phenylacetylene) is an adduct of two complexes, namely, (Acac)PdBF4 and [(PA)2Pd(C3-Acac · BF3)]+(Acac · BF3) (coordinatively unsaturated). On dissolution in deuteroacetone or deuteromethanol, the [(Acac)PdF2BF2Pd(C3-Acac · BF3)(PA)2]+(Acac · BF3) adduct decomposed to Pd(Acac)2, 2BF3 · L (L = (CD3)2CO, CD3OD) and the [L(PA)2Pd(C3-Acac]+BF4 complex.  相似文献   

14.
One-pot oxidation of R3Sb (R=Ph, Me, Cl, or C6F5) withtert-butyl hydroperoxide in the presence of 1,2-diols and monodentate donor compounds was studied. The structures of the resulting neutral organic donor-acceptor SbV complexes, Ph3(C6H4O2)Sb…OSMe2, Ph3(C6H4O2)Sb…ONC5H5, Me3(C6H4O2)Sb…ONC5H5, Me3(C6H4O2)Sb…NC5H5, Ph3(C2H4O2)Sb…ONC5H5, and Cl(C6F5)2(C2H4O2)Sb…OPPh3, were established by X-ray diffraction analysis. In these complexes, the coordination environment about the Sb atoms is a distorted octahedron. The Sb?O(N) distances and the Sb?O?E angles (E=S, N, or P) vary over wide ranges.  相似文献   

15.
The crystals of copper(I) π-complexes CuBF4 · 2C6H4N3(OC3H5) · H2O (I) and CuCF3COO · C6H4N3(OC3H5) (II) were obtained by alternating-current electrosynthesis and studied by X-ray diffraction: I, space group P21/n, a = 10.226(8), b = 13.233(10), c = 16.30(1) Å, β = 98.13(1)°, V = 2249(2) Å3, Z = 4, R = 0.0705, 577 reflections; I, space group P $ P\bar 1 The crystals of copper(I) π-complexes CuBF4 · 2C6H4N3(OC3H5) · H2O (I) and CuCF3COO · C6H4N3(OC3H5) (II) were obtained by alternating-current electrosynthesis and studied by X-ray diffraction: I, space group P21/n, a = 10.226(8), b = 13.233(10), c = 16.30(1) ?, β = 98.13(1)°, V = 2249(2) ?3, Z = 4, R = 0.0705, 577 reflections; I, space group P , a = 8.8625(7), b = 9.0647(4), c = 9.1650(5) ?, α = 68.37(2)°, β = 85.31(3)°, γ = 69.86(2)°, V = 646(4) ?3, Z = 2, R = 0.1354, 2669 reflections. In compound I, the tetrahedrally distorted trigonal pyramidal environment of the copper atom comprises two nitrogen atoms of two organic molecules (L), the C=C bond of another L molecule, and the O atom of the water molecule. Due to the bridging function of L molecule, infinite chains [Cu · 2C6H4N3(OC3H5) · H2O] n are formed in the structure along the y axis. The chains are, in turn, assembled into layers through strong O-H…F hydrogen bonds involving both hydrogen atoms of the water molecule and fluorine atoms of the BF4 anion. In compound II, two bridging oxygen atoms of two trifluoroacetate anions and two copper atoms form a centrosymmetric dimer. The nitrogen atom of the benzotriazole ring of one molecule L and the C=C double bond of the allyl group of the other molecule L complete the distorted coordination tetrahedron of the metal atom. Owing to the bridging function of the L molecule, the [CuCF3COO · C6H4N3(OC3H5)]2 dimers are connected to form infinite double chains associated in a three-dimensional framework by only weak interactions. The replacement of the covalently bonded trifluoroacetate anion by an outer-sphere tetrafluoroborate ion opens up the possibility for metal atom binding to three L molecules simultaneously. Original Russian Text ? E.A. Goreshnik, M.G. Mys’kiv, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 11, pp. 826–830.  相似文献   

16.
RE(C7H5O3)2(C9H6NO)配合物抗真菌作用的热动力学研究   总被引:6,自引:0,他引:6  
应用微量热法研究了配合物RE(CTH5O3)2(C9H6NO)(RE代表La,Sm和Nd)对真菌的抗菌作用。在TAM Air热导式等温微量量热仪上,分别测定了桔青霉菌和黑曲霉菌在不同浓度不同稀土配合物及空白条件下生长代谢热谱曲线,并计算得到了真菌在不同条件下的生长代谢速率常数k和传代时间G等热动力学参数。实验表明:3种稀土水杨酸8-羟基喹啉三元配合物对桔青霉菌和黑曲霉菌均有抑制作用,其抑制效果依次为:Sm(Hsal)2(hq)〉La(Hsal)2(hq)〉Nd(Hsal)2(hq)。  相似文献   

17.
Two new polyoxovanadates (Co(N(3)C(5)H(15))(2))(2)[{Co(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·5H(2)O (1) and (Ni(N(3)C(5)H(15))(2))(2)[{Ni(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·8H(2)O (2) (N(3)C(5)H(15) = N-(2-aminoethyl)-1,3-propanediamine) were synthesized under solvothermal conditions and structurally characterized. In both structures the [V(15)Sb(6)O(42)(H(2)O)](6-) shell displays the main structural motif, which is strongly related to the {V(18)O(42)} archetype cluster. Both compounds crystallize in the triclinic space group P1 with a = 14.3438(4), b = 16.6471(6), c = 18.9186(6) ?, α = 87.291(3)°, β = 83.340(3)°, γ = 78.890(3)°, and V = 4401.4(2) ?(3) (1) and a = 14.5697(13), b = 15.8523(16), c = 20.2411(18) ?, α = 86.702(11)°, β = 84.957(11)°, γ = 76.941(11)°, and V = 4533.0(7) ?(3) (2). In the structure of 1 the [V(15)Sb(6)O(42)(H(2)O)](6-) cluster anion is bound to a [Co(N(3)C(5)H(15))(2)](2+) complex via a terminal oxygen atom. In the Co(2+)-centered complex, one of the amine ligands coordinates in tridentate mode and the second one in bidentate mode to form a strongly distorted CoN(5)O octahedron. Similarly, in compound 2 an analogous NiN(5)O complex is joined to the [V(15)Sb(6)O(42)(H(2)O)](6-) anion via the same attachment mode. A remarkable difference between the two compounds is the orientation of the noncoordinated propylamine group leading to intermolecular Sb···O contacts in 1 and to Sb···N interactions in 2. In the solid-state lattices of 1 and 2, two additional [M(N(3)C(5)H(15))(2)](2+) complexes act as countercations and are located between the [{M(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)](4-) anions. Between the anions and cations strong N-H···O hydrogen bonds are observed. In both compounds the clusters are stacked along the b axis in an ABAB fashion with cations and water molecules occupying the space between the clusters. Magnetic characterization demonstrates that the Ni(2+) and Co(2+) cations do not significantly couple with the S = 1/2 vanadyl groups. The susceptibility data can be successfully reproduced assuming a distorted ligand field for the Co(2+) ions (1) and an O(h)-symmetric Ni(2+) ligand field (2).  相似文献   

18.
[(η5-C5H5)2Mo(η3-C3H5)]+ [p-CH3C6H4SO3] is conveniently synthesized by the reaction of (η5-C5H5)2MoH2 with allyl alcohol in the presence of p-toluene sulfonic acid, the mechanism of which is explained by the electrophilic cleavage of the allylO bond of the coordinated allyl alcohol.  相似文献   

19.
本文用电化学方法和X射线单晶结构分析, 研究了混合簇合物(C5H5FeC5H4C2Ph)Co2(CO)6的结构, 由循环伏安结果, 分别讨论了簇合物中(C5H5FeC5H4和C2O2中心的成键性质, X射线单晶结构分析表明: 晶体属单斜晶系, 空间群为P21, 晶胞参数a=11.845(6), b=8.155(6), c=24.031(6)A, β=90.88°,晶胞中分子数Z=4, 密度Do=1.637g.cm^-^2, 分析了(C5H5FeC5H4C2Ph)Co2(CO)6的结构特点, 并从成键角度讨论了(RC2R^1)Co(CO)6类簇合物的结构随RC2R^1不同而变化的规律。  相似文献   

20.
本文用电化学方法和X射线单晶结构分析, 研究了混合簇合物(C5H5FeC5H4C2Ph)Co2(CO)6的结构, 由循环伏安结果, 分别讨论了簇合物中(C5H5FeC5H4和C2O2中心的成键性质, X射线单晶结构分析表明: 晶体属单斜晶系, 空间群为P21, 晶胞参数a=11.845(6), b=8.155(6), c=24.031(6)A, β=90.88°,晶胞中分子数Z=4, 密度Do=1.637g.cm^-^2, 分析了(C5H5FeC5H4C2Ph)Co2(CO)6的结构特点, 并从成键角度讨论了(RC2R^1)Co(CO)6类簇合物的结构随RC2R^1不同而变化的规律。  相似文献   

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