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1.
Peter C. Junk  Jonathan W. Steed   《Polyhedron》1999,18(27):4646-3597
[Co(η2-CO3)(NH3)4](NO3)·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O were prepared by prolonged aerial oxidation of a solution of Co(NO3)2·6H2O and ammonium carbonate in aqueous ammonia. The formation of these side products highlights the richness of the chemistry of these systems and the possibility of by products if methods are not strictly adhered to. The X-ray crystal structures of [Co(η2-CO3)(NH3)4][NO3]·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O reveal a monomeric octahedral cobalt center with η2-bound CO32− in the former, while the latter consists of a dimeric array where the two cobalt centers are bridged by two OH and one μ2-CO32− groups with three terminal NH3 ligands for each Co center. In both complexes extensive hydrogen bonding interactions are evident.  相似文献   

2.
The compound [Zn(H2O)4]2[H2As6V15O42(H2O)]·2H2O (1) has been synthesized and characterized by elemental analysis, IR, ESR, magnetic measurement, third-order nonlinear property study and single crystal X-ray diffraction analysis. The compound 1 crystallizes in trigonal space group R3, a=b=12.0601(17) Å, c=33.970(7) Å, γ=120°, V=4278.8(12) Å3, Z=3 and R1(wR2)=0.0512 (0.1171). The crystal structure is constructed from [H2As6V15O42(H2O)]4− anions and [Zn(H2O)4]2+ cations linked through hydrogen bonds into a network. The [H2As6V15O42(H2O)]6− cluster consists of 15 VO5 square pyramids linked by three As2O5 handle-like units.  相似文献   

3.
(C6H5)3MX2 (M = As, Sb; X = OCOCF3 and M = Sb, Bi; X = SO3F, SO3CF3) compounds prepared by the interaction of triphenylmetal(V) substrates with (CF3CO)2O, (CF3SO2)2O and (FSO2)2O have been characterized by molecular weight determination, elemental and spectroscopic (IR, 1H and 19F NMR, mass) analyses.  相似文献   

4.
Chromium doped (CH3)2NH2Al(SO4)2·6H2O (DMAAlS) and (CH3)2NH2Ga(SO4)2·6H2O (DMAGaS) single crystals were grown and investigated using the methods of optical spectroscopy. It was found that the Cr3+ ions in the two crystals are situated in a strong crystal field in which the 2E state is the lowest. The single narrow R-line associated with the 2E–4A2 phosphorescence of Cr3+ in DMAAlS in a ferroelectric phase indicates an undistorted octahedral site, whereas important distortion of Oh symmetry and structural disorder was inferred from spectral data obtained with DMAGaS:Cr3+ in a low temperature phase. Results of optical investigation are discussed taking into account the structural data.  相似文献   

5.
Treatment of CpMoC13(MeCN)2 with SbCl5 in acetonitrile solution provides the solvated cationic series [CpMoCl2(MeCN)3]+, [CpMoCl(MeCN)4]2+ and [CpMo(MeCN)6]3+ as hexachloroantimon(V)ate salts following sequential halide abstraction. Characterization follows from microanalytical and spectroscopic (IR, and 1H NMR) data and, in the case of [CpMoCl(MeCN)4][SbCl6]2 · MeCN, by X-ray crystallographic studies. The structure is disordered but individual cations contain a six coordinated pseudo-octahedral metal geometry in which the cyclopentadienyl ligand (regarded as unidentate) and the chlorine atom occupy axial positions with an equatorial array of four acetonitrile ligands.  相似文献   

6.
Two hydrogen-bonded supramolecular compounds having the general formula [M(H2O)6][H2L] (M=MnII or CoII and H4L=1,2,4,5-benzenetetracarboxylic acid), have been newly prepared by the reaction of [M(H2O)6](ClO4)2 and [C6H2(COOH)4] (H4L), and structurally characterized by X-ray diffraction. The metal center in each compound is six-coordinated, forming an ideal octahedral geometry. Both neutral formula units make unique three-dimensional supramolecular architectures through hydrogen bonds and stabilized by electrostatic force.  相似文献   

7.
The potential of Fe(CO)41-dppf) (dppf = 1,1′-bis(diphenylphosphino)ferrocene) as a precursor for heterometallic species is fully expanded in the synthesis of (OC)4Fe(μ-dppf)Cr(CO)5, (OC)4Fe(μ-dppf)W(CO)5, and (OC)4Fe(μ-dppf)Mn2(CO)9, all of which have been characterized by IR, NMR (1H and 31P) and elemental analyses. The low energy requirement of TMNO (Me3NO · 2H2O)decarbonylation allows the formation of monosubstituted Mn2(CO)10 as the major product. This aspect is further substantiated by the isolation of Mn4(CO)18(μ-dppf) in which the single bridging of a diphosphine group between two Mn2(CO)9 moieties is unprecedented.  相似文献   

8.
在水热和弱酸性反应条件下,螯合型表面活性剂前驱体乙二胺三乙酸分别与氯化锌、氯化钴反应,形成水合乙二胺三乙酸金属配合物[M(H2O)6][M(ED3A)(H2O)]2·2H2O[M=Zn(1),Co(2);H3ED3A=乙二胺三乙酸,C8H14N2O6]。 产物经元素分析、红外、热重、液体核磁共振和X射线单晶衍射结构表征。 乙二胺三乙酸和锌(Ⅱ)、钴(Ⅱ)五配位,并与水一起形成典型的[MN2O4]或[MO6]八面体结构。 13C核磁共振实验结果表明,溶液中乙二胺三乙酸与锌形成配合物在弱酸性条件下(pH值3~7)稳定存在,在酸性溶液中完全解离,乙二胺三乙酸进一步经分子内成环反应生成3-酮哌嗪二乙酸(H2kpda=C8H12N2O5)。  相似文献   

9.
The reaction of Ln(NO3)3·6H2O (Ln=La, Ce, Pr or Nd) with a sixfold excess of Ph3PO in acetone formed [Ln(Ph3PO)4(NO3)3]·Me2CO. The crystal structure of the La complex shows a nine-coordinate metal centre with four phosphine oxides, two bidentate and one monodentate nitrate groups, and PXRD studies show the same structure is present in the other three complexes. In CH2Cl2 or Me2CO solutions, 31P NMR studies show that the complexes are essentially completely decomposed into [Ln(Ph3PO)3(NO3)3] and Ph3PO. Similar reactions in ethanol gave [Ln(Ph3PO)3(NO3)3] only. In contrast for Ln=Sm, Eu or Gd, only the [Ln(Ph3PO)3(NO3)3] are formed from either acetone or ethanol solutions. For the later lanthanides Ln=Tb–Lu, acetone solutions of Ln(NO3)3·6H2O and Ph3PO gave [Ln(Ph3PO)3(NO3)3] only, even with a large excess of Ph3PO, but from cold ethanol [Ln(Ph3PO)4(NO3)2]NO3 (Ln=Tb, Ho–Lu) were obtained. The structure of [Lu(Ph3PO)4(NO3)2]NO3 shows an eight-coordinate metal centre with four phosphine oxides and two bidentate nitrate groups. In solution in CH2Cl2 or Me2CO the tetrakis-complexes show varying amounts of decomposition into mixtures of [Ln(Ph3PO)3(NO3)3], [Ln(Ph3PO)4(NO3)2]NO3 and Ph3PO as judged by 31P{1H} NMR spectroscopy. The [Ln(Ph3PO)3(NO3)3] also partially decompose in solution for Ln=Dy–Lu, forming some tetrakis(phosphine oxide) species.  相似文献   

10.
The reaction of [(C6H6)RuCl2]2 with 7,8-benzoquinoline and 8-hydroxyquinoline in methanol were performed. The obtained complexes have been studied by IR, UV–VIS, 1H and 13C NMR spectroscopy and X-ray crystallography. In the reaction with 8-hydroxyquinoline the arene ruthenium(II) complex oxidized to Ru(III). The electronic spectra of the obtained compounds have been calculated using the TDDFT method. Magnetic properties of [Ru(C9H6NO)3] · CH3OH complex suggest the antiferromagnetic coupling of the ruthenium centers in the crystal lattice. EPR spectrum of [Ru(C9H6NO)3] · CH3OH compound indicates single isotropic line only characteristic for Ru3+ with spin equal to 1/2.  相似文献   

11.
A new sodium cobalt carbonate hydroxide hydrate, Na2Co8(CO3)6(OH)6·6H2O, has been prepared at room temperature by treatment of Co(OH)NO3·H2O with a concentrated aqueous solution of NaHCO3. X-Ray powder diffractometry and the results of the chemical analyses show that the compound is isotypical to Na2Ni8(CO3)6(OH)6·6H2O —kambaldaite, a unique mineral with no known synthetic or natural analogues.  相似文献   

12.
[Re2(Ala)4(H2O)8](ClO4)6 (Re=Eu, Er; Ala=alanine) were synthesized, and the low-temperature heat capacities of the two complexes were measured with a high-precision adiabatic calorimeter over the temperature range from 80 to 370 K. For [Eu2(Ala)4(H2O)8](ClO4)6, two solid–solid phase transitions were found, one in the temperature range from 234.403 to 249.960 K, with peak temperature 243.050 K, the other in the range from 249.960 to 278.881 K, with peak temperature 270.155 K. For [Er2(Ala)4(H2O)8](ClO4)6, one solid–solid phase transition was observed in the range from 270.696 to 282.156 K, with peak temperature 278.970 K. The molar enthalpy increments, ΔHm, and entropy increments,ΔSm, of these phase transitions, were determined to be 455.6 J mol−1, 1.87 J K−1 mol−1 at 243.050 K; 2277 J mol−1, 8.43 J K−1 mol−1 at 270.155 K for [Eu2(Ala)4(H2O)8](ClO4)6; and 4442 J mol−1, 15.92 J K−1 mol−1 at 278.970 K for [Er2(Ala)4(H2O)8](ClO4)6. Thermal decompositions of the two complexes were investigated by use of the thermogravimetric (TG) analysis. A possible mechanism for the thermal decomposition is suggested.  相似文献   

13.
A novel N6 macrocyclic ligand, L1 (2,8,14,20-tetramethyl-3,7,15,19,25,26-hexaaza-tricyclo[19.3.1.19,13]hexacosa-1(24),9,11,13(26),21(25),22-hexaene), was obtained by reduction of the 2 + 2 condensation product of 2,6-diacetylpyridine and propane-1,3-diamine. Zinc(II) complexes of L1, of a related N8 macrocycle, L3 (3,6,9,17,20,23,29,30-octaaza-tricyclo[23.3.1.1[11,15]]triaconta-1(28),1,13,15(30),25(29),26-hexaene), similarly prepared by 2 + 2 condensation of 2,6-diformylpyridine and diethylenetriamine and of a tetra N-2-cyanoethyl derivative of a homologue of L1 prepared from diformyl pyridine and ethane-1,2-diamine, L2 (3-[6,14,17-tris-(2-cyano-ethyl)-3,6,14,17,23,24-hexaaza-tricyclo[17.3.1.18,12] tetracosa-1(23),8(24),9,11,19,21-hexaen-3-yl]-propionitrile), were prepared. Structures were determined for [ZnL1](ClO4)2 · H2O, [ZnL2](NO3)2 and [Zn2L3(NO3)2](NO3)2 · H2O. The [ZnL1](ClO4)2 · H2O and [ZnL2](NO3)2 complexes present a mononuclear endomacrocyclic structure with the metal in an octahedral distorted environment coordinated by the six donor nitrogen atoms from the macrocyclic backbone while the complex [Zn2L3(NO3)2](NO3)2 · H2O is dinuclear with both metal atoms into the macrocyclic cavity coordinated by four donor nitrogen atoms from the macrocyclic framework and one oxygen atom from one monodentate nitrate anion, in a distorted square pyramidal arrangement.  相似文献   

14.
The synthesis and structural characterization of new hydroxo-fluorometallates [H3N(CH2)6NH3]2M(F,OH)7·H2O (M=Al, In) are presented. Their preparation is achieved in solvothermal conditions by microwave or classical heating. The isotopic structures, determined by single crystal X-ray diffraction, are triclinic with the space group P–1. The structural arrangement can be described from isolated MX6 (X=F, OH) octahedra connected by diprotonated diaminohexane via a complex network of hydrogen bonds. X anions and water molecules are found between the organic chains. A study by 19F NMR of the Al compound confirms a statistical occupancy of fluorine sites by hydroxyl groups and the occurrence of isolated F anions.  相似文献   

15.
A new family of heteropolytungstate complexes (NH4)21[Ln(H2O)5{Ni(H2O)}2As4W40O140xH2O(Ln=Y, Ce, Pr, Nd, Sm, Eu, Gd) were prepared by the reaction of Na27[NaAs4W40O140]·60H2O with NiCl2·6H2O and Ln(NO3)3·xH2O at pH≈4.5. The crystal structures of (NH4)21[Gd(H2O)5{Ni(H2O)}2As4W40O140]·51H2O was determined by X-ray diffraction analysis and element analysis. The compound crystallizes in the monoclinic space group P21/n with a=19.754(3), b=24.298(4), c=39.350(6) Å, β=100.612(3)°, V=18564(5) Å3, Z=2, R1(wR2)=0.0544(0.0691). The central site S1 and two opposite sites S2 of the big cyclic ligand [As4W40O140]28− are occupied by one Ln3+and two Ni2+, respectively, each site supply four Od coordinating to metal ion, another one water molecule and other five water molecules coordinate, respectively, to Ni2+and Ln3+. Polyanion [Ln(H2O)5{Ni(H2O)}2As4W40O140]21− has C2v symmetry. IR and UV–vis spectra of [NaAs4W40O140]27− of the title compounds are discussed.  相似文献   

16.
Synthesis, structure, spectroscopy and thermal properties of complex [Co(NCS)2(hmt)2(H2O)2][Co(NCS)2(H2O)4] (H2O) (I), assembled by hexamethylenetetramine and octahedral Co(II) metal ions, are reported. Crystal data for I: Fw 387.34, a=9.020(8), b=12.887(9), c=7.95(1) Å, =96.73(4), β=115.36(5), γ=94.16(4)°, V=820(1) Å3, Z=2, space group=P−1, T=173 K, λ(Mo-K)=0.71070 Å, ρcalc=1.718567 g cm−3, μ=17.44 cm−1, R=0.088, Rw=0.148. An interesting two-dimensional network is assembled via hydrogen bonds through coordinated and free water molecules. The d–d transition energy levels of Co(II) ion are determined by UV–vis spectroscopy and calculated by ligand field theory. The calculated results agree well with experiment ones.  相似文献   

17.
The title complex [ErY(Gly)_6(H_2O)_4](ClO_4)_6 5H_2O has been synthesized.Its crystalstructure has been determined by X-ray diffraction method.The crystal is triclinic with space groupP1.The unit cell parameters are as follows:a=11.518(4),b=14.105(7),c=15.530(6) ,α=96.61(3),β=102.74(3),γ=105.70(3)°,V=2327.7(17) ~3,Z=2,Dc=2.091g/cm~3.The structure has been refinedto a final R of 0.0785.The crystal is an infinite chain complex,in which four carboxyl groups fromglycine molecules bridge the Er(Ⅲ)and Y(Ⅲ)ion,other two carboxyl groups bridge two adjacentEr(Ⅲ)or two Y(Ⅲ)ions.  相似文献   

18.
The bright red title compound 1 was synthesized from (2-lithiophenyl)diphenylamine and bis(pentafluorophenyl)boron chloride. Its reactions with small acids like H2O and HCl proceeded easily giving zwitterionic compounds. For 1 and its water adduct 2 the crystal structures were determined, the latter featuring an ammonium borate structure containing a short intramolecular hydrogen bond bridge. Treatment of 1 with Jutzi's acid, [H(OEt2)2][B(C6F5)4], did not result in protonation of the nitrogen, but reaction of 1 with LiH in the presence of 12-crown-4, led to the isolation of the aminoborate [1-(Ph2N)-2-{B(H)(C6F5)2}C6H4][Li(12-crown-4)] (3). Borohydride 3 reacted with Jutzi's acid to regenerate 1 and liberate hydrogen.  相似文献   

19.
A series of rhenium complexes [fac-Re(bpy)(CO)3L][SbF6] (bpy = 2,2′-bipyridine, L = P(nBu)3, PEt3, PPh3, P(OMe)Ph2, P(OiPr)3, P(OEt)3, P(OMe)3, P(OPh)3) has been prepared and characterized by the IR, UV-vis, 1H NMR, 31P NMR, X-ray photoelectron spectroscopy and electrochemical techniques. Variations in the electronic properties, i.e. CO stretching, metal-to-ligand charge transfer transition, and 31P NMR chemical shifts were interpreted on the basis of the electron-acceptor strength of L. However, the redox potential corresponding to [Re(bpy)(CO)3L]+/[Re(bpy)(CO)3L]showed ‘V-character type’ changes after the increase in the electron-acceptor strength of L. Variation of the P(2p) binding energy of the phosphorus atom indicated that the electronic structure of the coordinated phosphorus atom was strongly influenced by the electronic properties of the directly attached substituents.  相似文献   

20.
A novel tetranuclear terbium(III) complex [Tb4(OH)4(pybet)6(H2O)8][Tb4(OH)4(pybet)6(H2O)7 (NO3)](ClO4)14·6H2O has been synthesized and shown by X-ray crystallography to have a cubane-like Tb43-OH)42-carboxylato-O,O′)6 core. The ligand pybet is pyridinoacetate, C5H5+N-CH2CO2. Magnetic susceptibility data were measured for this Tb4 complex in the range of 2.0–320 K and in fields of 1.0 G to 50.0 kG. It is concluded that either there is very weak antiferromagnetic exchange interaction (J = −0.015 cm−1) or there is a small crystal-field splitting of the 7F6 TbIII ground state.  相似文献   

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