首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Antimony(III)pentafluoroorthotellurate has been synthesized from SbF3 and B(OTeF5)3. Contrary to a previous report it is a low melting, sublimable solid (mp = 28°, bp (0.1 torr) = 68°, 19F - NMR: AB4 spinsystem δ (A) = ?42.7, δ (B) = ?38.1, J (AB) = 186 Hz). It reacts with F2, Cl2 and Br2 to give SbF2(OTeF5)3, SbCl4+Sb(OTeF5)6? and SbBr4+ Sb(OTeF5)6? respectively. Interaction of Xe(OTeF5)2 and Sb(OTeF5)3 yields Sb(OTeF5)5, which is unstable at room temperature. Salts containing the new anion Sb(OTeF5)6? have been synthesized either from Sb(OTeF5)5 and a corresponding pentafluoroorthotellurate e.g. Sb(OTeF5)5 + NMe4+ OTeF5? = NMe4+ Sb(OTeF5)6?, or from SbCl4 Sb(OTeF5)6? and an appropriate chloride SbCl4+ Sb(OTeF5)6? + NOCl = SbCl5 + NO+ Sb(OTeF5)6?, or oxidatively, using a mixture of Xe(OTeF5)2 and Sb(OTeF5)5, e.g. C6F6 + 12 Xe(OTeF5)2 + Sb(OTeF5)5 = C6F6+ Sb(OTeF5)6? + 12 Xe.  相似文献   

2.
Two solid-state coordination compounds of rare earth metals with glycin, [Gd4/3Y2/3(Gly)6(H2O)4](ClO4)6·5H2O and [ErY(Gly)6(H2O)4](ClO4)6·5H2O were synthesized. The low-temperature heat capacities of the two coordination compounds were measured with an adiabatic calorimeter over the temperature range from 78 to 376 K. [Gd4/3Y2/3(Gly)6(H2O)4](ClO4)6·5H2O melted at 342.90 K, while [ErY(Gly)6(H2O)4](ClO4)6·5H2O melted at 328.79 K. The molar enthalpy and entropy of fusion for the two coordination compounds were determined to be 18.48 kJ mol−1 and 53.9 J K−1 mol−1 for [Gd4/3Y2/3(Gly)6(H2O)4](ClO4)6·5H2O, 1.82 kJ mol−1 and 5.5 J K−1 mol−1 for [ErY(Gly)6(H2O)4](ClO4)6·5H2O, respectively. Thermal decompositions of the two coordination compounds were studied through the thermogravimetry (TG). Possible mechanisms of the decompositions are discussed.  相似文献   

3.
The rate of the reaction
has been investigated at 40–65°C with [HClO4] varying from 0.04 to 0.6 M (μ = 0.6 M, NaClO4). The observed rate law has the form: -d[Cr(NH3)5(NCO)2+]/dt = kobs[Cr(NH3)5(NCO)2+] where kobs = a[H+]2{1 + b[H+]2} and ?1 at 55.0°C, a = 0.36 M?1 s?2 and b = 6.9 × 10?3 M?1 s?1. The rate of loss of Cr(NH3)5(NCO)2+ increases with increasing acidity to a limiting value (at [H+] ~ 0.5 M) but the yield of Cr(NH3)63+ decreases with increasing [H+] and increases with increasing temperature. In the kinetic studies the maximum yield of Cr(NH3)63+ was 35% but a synthetic procedure has been developed to give a 60% yield.  相似文献   

4.
Incoherent quasi-eleastic neutron scattering experiments: using different resolutions and a wide Q range, have been performed on polycrystalline samples of Cr(CO)36C6H6) and Mn(CO)35C5H5) in the 280–320 K temperature range. It is shown that aromatic rings are involved into a reorientational process characterized by an activation energy of ≈ 16 kJ mol?1 and by correlation times of the order of 2 × 10?11 s and 5 × 10?11 s at 300 K for C6H6 and C5H5 rings respectively. Experimental elastic incoherent structure factors are in agreement with the 2π/6 and 2π/5 jump models and the fitted spectra confirm these models. From a comparison with heat-capacity results we conclude that M(CO)3 groups are fixed during the reorientational process. Finally a comparison with literature data is presented.  相似文献   

5.
The electronic absorption spectrum of (η5-C5H5)Mn(CO)2[C(C6H5)2]shows an intense maximum which is assigned to a MLCT transition in which the empty pπ orbital on the carbene carbon is populated. Upon irradiation of this band, the complex undergoes a decomposition with a disappearance quantum yield Φ = 0.10 ± 0.01 independent of solvent. In the CT excited state, the complex can be roughly described as containing d5 MnII and a diphenylcarbene radical anion ligand C(C6H5)2?. Due to the kinetic lability, the complex decomposes producing a MnII species and the free carbene radical anion, which then undergoes secondary reactions. In addition, small amounts of substitution product are observed. It is proposed that prior to total decomposition of the excited state, a radical pair (η5-C5H5)Mn(CO)2S+/C(C6H5)2?forms (S = solvent). A back electron transfer from C(C6H5)2?to the labile cation competes with decomposition to produce the substituted complex and free carbene.  相似文献   

6.
Treatment of MBr(CO)5 (M = Mn or Re) with AgClO4 and an organonitrile in a suitable solvents affords the complexes fac-[M(CO)3(NCR)3][ClO4], (R = Et, Pr or PhCH2). The use of these complexes as synthetic precursors has been illustrated by the preparation of fac-[M(CO)3L3][ClO4], (M = Mn, L = NH3 or L3 = dien; M = Re, L3 = triphos). Pure fac-[Re(CO)3(NH3)3][ClO4] could not be prepared using this nitrile displacement route, but may be isolated, as the PF6? salt, from the reaction of [Re(CO)3(toluene)][PF6] and ammonia in chloroform.  相似文献   

7.
Two copper(I) complexes [Cu(Cin2bda)2]ClO4 (I) and [Cu(Ncin2bda)2]ClO4 (II) have been prepared by the reaction of the ligands N2,N2′-bis(3-phenylallylidene)biphenyl-2,2′-diamine (L1) and N2,N2′-bis[3-(2-nitrophenyl)allylidene]biphenyl-2,2′-diamine (L2) and copper(I) salt. These compounds were characterized by CHN analyses, 1H NMR, IR, and UV-Vis spectroscopy. The C=N stretching frequency in the copper(I) complexes shows a shift to a lower frequency relative to the free ligand due to the coordination of the nitrogen atoms. The crystal and molecular structure of II was determined by X-ray single-crystal crystallography. The coordination polyhedron about the copper(I) center in the complex is best described as a distorted tetrahedron. A quasireversible redox behavior was observed for complexes I and II. The article is published in the original.  相似文献   

8.
The infrared spectra of the complexes [M(pyO)6](ClO4)2 (pyO = pyridine N-oxide; M = Mn, Fe, Co, Ni, Zn) are discussed. Assignments of v(M-O) and other significant vibrations are based on the band shifts induced by deuteration of the heterocyclic ring and the effects of metal ion substitution. Earlier spectroscopic evidence suggesting distortion from regular octahedral site symmetry is discounted by the far-infrared spectra. In agreement with recent crystallographic evidence for Oh site symmetry in these complexes, one infrared-active v(M-O) band is expected and observed. The effects on the spectra of structural distortion in the 6-coordinate CuII complex [Cu(pyO)6](ClO4)2, reduced coordination number in the 4-coordinate complex [Cu(pyO)4](C1O4)2, and increased cationic charge in the GaIII complex [Ga(pyO)6](C1O4)3are discussed.  相似文献   

9.
The reactions of Fe(CO)5, Fe(CO)4P(C6H5)3, M(CO)6 (M  W, Mo, Cr), and (CH3C5H4Mn(CO)3 with KH and several boron and aluminium hydrides were investigated. Iron pentacarbonyl was converted quantitatively to K+Fe(CO)4-(CHO) by hydride transfer from KBH(OCH3)3 allowing isolation of [P(C6H5)3]2-Nn+Fe(CO)4(CHO)? in 50% yield. Lower yields were obtained with LiBH(C2H5)3, and other hydride sources gave little or no formyl product. The stability of Fe(CO)4(CHO)? in THP was found to depend on the cation, decreasing in the order [P(C6H5)3]2N+ > K+ > Na+ > Li+. No formyl complexes were isolated and no spectroscopic evidence for formyl formation was observed in the reactions of the other transition metal carbonyls with several hydride sources. Fe(CO)4-P(C6H5)3 gave K2Fe(CO)4 when treated with KHB(OCH3)3. When treated with LiBH(C2H5)3, W(CO)6 gave a mixture of HW2(CO)10?and (OC)5W(COC2H5)?; the latter was methylated to give the carbene complex (OC)5WC(OCH3)C2H5.  相似文献   

10.
The cocrystallization method is used to obtain a new volatile heterometallic complex of the composition [Cu(ki)2·Pb(hfa)2]2, where ki = 2-iminopentan-4-onate and hfa = hexafluoroacetylacetonate. The crystallographic data for C20H18CuF12N2O6Pb: a = 10.6729(5)?, b = 10.7712(5)?., c = 13.4779(5)?.; α = 79.1020(10)°, β = 84.5140(10)°, γ = 66.2470(10)°, P-1 space group, Z = 2, d x = 2.102 g/cm3. The compound has a molecular structure built of individual Cu...Pb...Pb...Cu-type tetramers. The Cu...Pb and Pb...Pb distances in the tetramer are 3.454. and 4.122. respectively; the Cu-Pb-Pb angle is 160.7°.  相似文献   

11.
Specific heat data on (BA)2Cu(Ox)2 and (CHA)2Cu(Ox)2·H2O below 1 K are reported (BA = C6H5 CH2NH3+, CHA = C6H3+, Ox = C2O42). The magnetic contributions have the form of broad maxima, occurring near 0.15. A λ-type anomaly is observed for (BA)2Cu(Ox)2 at Tc = 0.116(3) K. For (CHA)2Cu(Ox)2·H2O no such ordering is seen.(BA)2Cu(Ox)2 appears to be a quadratic S = 1/2 Heisenberg antiferromagnet with J/k = ?0.145 (3) K. The compound (CHA)2Cu(Ox)2·H2O shows a behaviour that is in between 1-D and 2-D S = 1/2 Heisenberg antiferromagnetism.  相似文献   

12.
The X-ray crystal structures of (NH4)2(15-crown-5)3[Cu(mnt)2] (1) and (NH4)2(benzo-15-crown-5)4- [Cu(mnt)2]·0.5H2O (2) were determined. Two single crystals are composed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2]2- anion. The triple-decker dication in complex 1 and a sandwich dimmer in complex 2 were observed. X-Band EPR studies on the single crystals of both complex 1 and complex 2 have been carried out at room temperature, which revealed that complex 2 showed a perfect hyperfine structure of Cu whereas that of complex 1 could not be observed. The principal values and direction cosines of the principal axes of the g and A tensors were computed by a least-squares fitting procedure. The spin density of Cu(Ⅱ) was estimated according to the principal values of the A tensors and compared well with the results calculated based on DFT method.  相似文献   

13.
Complexes of the type [Ir(COD){P(p-RC6H4)3}2]A (R  Cl, F, H, CH3 or CH3O; A  ClO4? or B(C6H5)4?) have been prepared and their reactions with halogens, methyl iodide, chlorotrimethylsilane, carbon monoxide and hydrogen have been studied. The catalytic activity of the complexes in the hydrogenation of mono- and diolefins depends upon the basicity of the phosphine present.  相似文献   

14.
利用微波技术合成了配合物[Gd2(Gly)6(H2O)4](ClO4)6(H2O)5, 进行了化学成分分析、红外表征和热重分析. 应用X衍射仪测定其晶体结构, 该晶体为一维链结构, 属三斜晶系, P 空间群, 晶胞参数: a=1.1569(17) nm, b=1.4138(2) nm, c=1.5642(2) nm, α=96.910(2)°, β=102.735(2)°, γ=105.512(2)°, V=2.3606(6) nm3, Z=2, Dc=2.144 g•cm-3. 采用精密溶解-反应量热计, 通过设计热化学循环, 计算出了该配合物的标准摩尔生成焓为 -(7960.73±3.23) kJ•mol-1.  相似文献   

15.
A dinuclear copper(Ⅱ) complex[Cu2(TATP)2(L-Leu)2(CIO4)2]2·2H2Owas synthesized and characterized, where, TATP=1,4,8,9-tetraazatriphenylene, and L-Leu=L-leucinate. The complex was crystallized in the triclinic space group P1, with two independent molecules in a unit cell. Two Cu(Ⅱ) ions in each complex [Cu2(TATP)2(L-Leu)2(CIO4)2] molecule were found to be in different coordination geometries, i.e., Cu2 or Cu4 of a distorted square-pyramidal geometry coordinated with two nitrogens of TATP, the amino nitrogen and one carboxylate oxygen of L-Leu and one oxygen of perchlorate, and Cul or Cu3 with an octahedral geometry coordinated with the above stated similar coordinated atoms, and another carboxylate oxygen of L-Leu coordinating to Cu2 or Cu4. The complex can interact with CT-DNA by an intercalative mode and cleave pBR322 DNA in the presence of ascorbate.  相似文献   

16.
Double complex salts (DCSs) [Co(NH3)6][Fe(CN)6] (I) and [Co(NH3)6]2[Cu(C2O4)2]3 (II) and complex [Co(NH3)6]2(C2O4)3·4H2O (III) are synthesized and investigated by single crystal XRD, crystal optics, and elemental analysis. The crystalline phases of I, II, and III (R-3, P21/c, and Pnnm space groups respectively) have the following crystallographic characteristics: a = 10.9804(2) ?, b = 10.9804(2) ?, c = 10.8224(3) ?, V = 1130.03(4) ?3, Z = 3, d x = 1.65 g/cm3 (I); a = 9.6370(2) ?, b = 10.2452(2) ?, c = 13.2108(3) ?, V = 1932.90(9) ?3, Z = 2, d x= 1.97 g/cm3 (II), and a = 11.7658(3) ?, b = 11.7254(3) ?, c = 14.1913(4) ?, V = 1304.34(5) ?3, Z = 2, d x = 1.68 g/cm3 (III). This paper investigates the products of DCS thermolysis in a hydrogen atmosphere: the intermetallic compound CoFe with the bcc parameter a = 2.852 ? for I and a heterogeneous mixture of Co and Cu in the decomposition of II. The coordinated CN and C2O42− groups then turn into NH3, hydrocarbons, and CO2. The dominant hydrocarbon is methane.  相似文献   

17.
Two new isomorphous tetranuclear complexes [Cu4L2(4,4′-bipy)2]·(ClO4)4·2CH3CN·2H2O (1) and [Zn4L2(4,4′-bipy)2]·(ClO4)3·CH3O·4H2O (2) have been obtained and fully characterized (where bipy = bipyridine, H2L = macrocycle is the [2+2] condensation product of 2,6-diformyl-4-fluoro-phenol and 1,4-diaminobutane). They exhibit wheel-like configuration in which two 4,4′-bipy molecules connect two dinuclear [M2L]2+ units. The interactions of the complexes with calf thymus DNA were studied by UV-Vis and CD spectroscopic techniques. The binding constants of 1 and 2 are 2.27 × 106 and 3.89 × 105 M−1, respectively. The magnetic measurement of 1 reveals that there are strong antiferromagnetic coupling (J = -272.6 cm−1) between two Cu(II) ions in the macrocyclic unit and ferromagnetic interaction (j′ = 41.7) between the Cu(II) ions in two adjacent macrocyclic units. Furthermore, the cyclic voltammogram of 1 shows that it undergoes two quasi-reversible processes with the half wave potentials -0.232 and -0.606 V, respectively.  相似文献   

18.
Two compounds, [Co(bpy)2(NiL)](ClO4)2 (1)and {[Co(phen)3](NiL)}(ClO4)2 (2), have been synthesized: (H2L=2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacylotetradeca-7,12-diene, bpy=2,2-bypyridine and phen = 1,10-phenanthroline). Compound (1) contains a discrete binuclear [Co(bpy)2(NiL)]2+ cation, while compound (2) is composed of [Co(phen)3]2+ cations and NiL neutral fragments. The magnetic properties of compound (1) have been dealt with by isotropic one-ion approximation of the CoII ion with a spin--orbit coupling in an Oh symmetry environment. The electronic spectra of these two compounds have also been discussed.  相似文献   

19.
Reactions of PdRR′(η1-dppm)2 (R = R′= C6F5 or C6Cl5; R = C6F5, R′= Cl; dppm = Ph2PCH2PPh2) with the gold derivatives ClAu(tht), C6F5Au(tht), (C6F5)3Au(tht) or O3ClOAuPPh3 (tht = tetrahydrothiophen) in appropriate ratios yield the bi- or tri-nuclear complexes PdRR′(dppm)2AuCl, PdRR′(dppm)2Au(C6F5); PdRR′(dppm)2Au(C6F5)3; PdRR′(dppmAuCl)2; PdRR′(dppmAuC6F5)2; PdRR′[dppmAu(C6F5)3]2, [PdRR′(dppm)2Au]X (X = ClO4 or BPh4); [PPh3Au(dppm)Pd(C6F5)2(dppm)AuCl]ClO4 or [PPh3 Au(dppm)Pd(C6F5)2(dppm)Au(C6F5)3]ClO4. The structure of trans-Pd(C6F5)2[dppmAu(C6F5)]2 has been determined by X-ray diffraction.  相似文献   

20.
Cerium(III) diammonium polyphosphate, (NH4)2Ce(PO3)5, is triclinic P1 with the following unit cell dimensions: a = 7.241(5) Å, b = 13.314(8) Å, c = 7.241(5)Å, α = 90.35(5)°, β′ = 107.50(5)°, γ = 90.28(5)°, and Z = 2, V = 665.7 Å3, Dx = 2.85 g/cm3. The crystal structure of this new type of polyphosphate has been solved and refined from 4130 independent reflections to a final R value 0.029. The most interesting feature of this salt is the existence of two infinite crystallographically nonequivalent (PO3)? chains, one running parallel to the a axis, the other along the c axis, both with a period of five tetrahedra. This compound seems to be the first example of a long chain polyphosphate with crystallographic independent chains.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号