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1.
A series of gold(III) cations of the type cis-[CH3)2AuL2]+ X? where L  Ph3, PMePh2, PMe2Ph, PMe3, AsPh3, AsPh3, SbPh3, 12H2NCH2CH2NH2, 12 Ph2PCH2CH2-PPh2, 12 Ph2AsCH2CH2AsPh2, and 12o-C6H4(AsMe2)2 and X  BF4?, PF6?, ClO4?, and F3CSO3? has been prepared. In addition, the cis complexes [(CH3)(CD3)-Au(PPh3)2]F3CSO3, [(C2H5)2Au(PPh3)2]F3CSO and [(n-C4H9)2Au(PPh3)2]F3-CSO3 have been synthesized. All have been characterized by PMR, Raman and infrared spectroscopy. These [R2AuL2]X compounds yield only ethane, butane, or octane via reductive elimination, and no disproportionation is observed. The alkane eliminations have been studied in CHCl3, CH3Cl2, and CH3COCH3 solution as a function of temperature, concentration of the complex, and concentration of added ligand L. Elimination is fastest when L is bulky (PPh3 > PMePh2 > PMe2Ph > PMe3), decreases in the sequence SbPh3 > AsPh3 > PPh3, is slow with chelating ligands, is inhibited by excess ligand, and there is small anion effect as X is varied. As R is varied, the rate of elimination decreases Bu ? Et > Me. An intramolecular dissociative mechanism is proposed which involves rapid elimination of alkane from an electron deficient dialkylgold(III) complex with nonequivalent gold—carbon bonds and produces the corresponding [AuL2]X complex.  相似文献   

2.
The mass spectra of the following acetylenic derivatives of iron, ruthenium and osmium carbonyls are reported: the iron compounds Fe2(CO)6[C2(C6H5)s2]2, Fe2(CO)6[C2(CH3)2]2 and Fe2(CO)6[C2(C2H5)2]2, the ruthenium compounds Ru2(CO)6[C2(C6H5)2]2, and Ru2(CO)6[C2(CH3)2]2 and the osmium compounds Os2(CO)6[C2(C6H5)2]2, Os2(CO)6[C2HC6H5]2 and Os2(CO)6[C2(CH3)2]2. Iron compounds exhibit breakdown schemes where binuclear, mononuclear and hydrocarbon ions are present. On the other hand, ruthenium and osmium compounds fragment in a similar way and give rise to singly and doubly charged binuclear ions. Phenylic derivatives of ruthenium and osmium also give weak triply charged ions. The results are discussed in terms of relative strengths of the metal-metal and metal-carbon bonds.  相似文献   

3.
The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe2: [(PbSe)1.14]4[NbSe2]4, [(PbSe)1.14]3[NbSe2]3[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]3[NbSe2]2[(PbSe)1.14]1[NbSe2]2, [(PbSe)1.14]2[NbSe2]3[(PbSe)1.14]2[NbSe2]1, [(PbSe)1.14]2[NbSe2]2[(PbSe)1.14]1[NbSe2]1[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]2[NbSe2]1[(PbSe)1.14]1[NbSe2]2[(PbSe)1.14]1[NbSe2]1. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance.  相似文献   

4.
The properties of (η55-C5H4C5H4)(C5H5)2Nb2(μ-NC6H5)2 (I) have been investigated. Reaction of I with acids (HCl, H2SO4 and CX3COOH) includes diprotonation to form the dication, [(η55-C5H4C5H4)(C5H5)2Nb2? (μ-NC6H5)2H2]2+ (II). The process is reversible and the initial neutral compound I may be recovered under the action of a base. The protonated compound II may lose NC6H5 ligands as C6H5NH3+; the paramagnetic product of the dissociation (C5H4C5H4)(C5H5)2Nb2Cl4 (III) has been isolated.  相似文献   

5.
The positive-ion mass spectra of the following organonitrogen derivatives of metal carbonyls are discussed: (i) The compounds NC5H4CH2Fe(CO)2C5H5, NC5H4CH2COMo(CO)2C5H5, NC5H4CH2W(CO)3C5H5, NC5H4CH2COMn(CO)4, C5H10NCH2CH2Fe(CO)2C5H5, (CH3)2NCH2CH2COFeCOC5H5 and (CH3)2NCH2CH2COMn(CO)4 obtained from metal carbonyl anions and haloalkylamines, (ii) The isocyanate derivative C5H5Mo(CO)3CH2NCO; (iii) The arylazomolybdenum derivatives RN2Mo(CO)2C5H5 (R ? phenyl, p-tolyl, or p-anisyl); (iv) The compound (C6H5N)2COFe2(CO)6 obtained from Fe3(CO)12 and phenyl isocyanate; (v) The N,N,N′,N′-tetramethylethylenediamine complex (CH3)2NCH2CH2N(CH3)2W(CO)4. Further examples of eliminations of hydrogen, CO, and C2H2 fragments were noted. In addition evidence for the following more unusual processes was obtained: (i) Elimination of HCN fragments from the ions [NC5H4CH2MC5H5]+ to give the ions [(C5H5)2M]+ (M ? Fe, Mo and W); (ii) Conversion of C5H5Mo(CO)3CH2NCO to C5H5Mo(CO)2CH2NCO within the mass spectrometer; (iii) Elimination of N2 from [RN2MoC5H5]+ to give [RMoC5H5]+; (iv) Novel eliminations of HNCO, FeNCO, and C6H5NC fragments in the mass spectrum of (C6H5N)2COFe2(CO)6; (v) Facile dehydrogenation of the N,N,N′,-N′-tetramethylethylenediamine ligand in the complex (CH3)2NCH2CH2N(CH3)2W(CO)4.  相似文献   

6.
Dissociative ionisation of organometallic cyclopentadiene derivatives containing one, two or three M(CH3)3 groups (M  Si, Ge, Sn) has been studied.Among the monometallated compounds, C5H5Si(CH3)2Cl, C5H5Si(CH3)2OCH3 and (C5H5)4Sb have also been investigated. To verify fragmentation patterns, the spectra of deuterated compounds such as C5D5Si(CH3)3, C5D5Sn(CH3)3, C5D4Si2(CH3)6 and C5D3Si3)9 have been measured. Dissociative ionisation of h1-cyclopentadienyl derivatives has been shown to differ essentially from that of h5-compounds.  相似文献   

7.
The Bi2Fe2(C2O4)5·5H2O was synthesized by solid-state reaction at low heat using Bi(NO3)3·5H2O, FeSO4·7H2O, and Na2C2O4 as raw materials. The nanocrystalline BiFeO3 was obtained by calcining Bi2Fe2(C2O4)5·5H2O at 600 °C in air. The precursor and its calcined products were characterized by thermogravimetry and differential scanning calorimetry, FT-IR, X-ray powder diffraction, and vibrating sample magnetometer. The data showed that highly crystallized BiFeO3 with hexagonal structure [space group R3c(161)] was obtained when the precursor was calcined at 600 °C in air for 1.5 h. The thermal process of the precursor in air experienced five steps which involved, at first, the dehydration of an adsorption water molecule, then dehydration of four crystal water molecules, decomposition of FeC2O4 into Fe2O3, decomposition of Bi2(C2O4)3 into Bi2O3, and at last, reaction of Bi2O3 and Fe2O3 into hexagonal BiFeO3. Based on Starink equation, the values of the activation energies associated with the thermal process of Bi2Fe2(C2O4)5·5H2O were determined. Besides, the most probable mechanism functions and thermodynamic functions (ΔS , ΔH , and ΔG ) of thermal processes of Bi2Fe2(C2O4)5·5H2O were also determined.  相似文献   

8.
Single-crystal optical absorption spectra of NiO, NiTiO3, NiWO4, NiV2O6, NiNb2O6, Ni2SiO4, Ni3V2O8, LiNiPO4, Li2Ni2Mo3O12, SrNiTeO6, LiScSiO4:Ni, MgSiO3:Ni, and (Mg,Ni)2SiO4 are presented for the purpose of comparing the spectra of yellow and green Ni2+ compounds. Powder spectra of NiTiO3, NiWO4, NiV2O6, NiNb2O6, and Ni3V2O8 in the ultraviolet region help elucidate the more intense charge transfer bands. Bright yellow color results when Ni2+ is in a six-coordinated site significantly distorted from octahedral symmetry. Increased absorption intensity occurs when the metal ion d-d bands are in proximity to an ultraviolet charge transfer band.  相似文献   

9.
Summary The organofunctional trisiloxanes Me3SiOSiMe(R)OSiMe3 [R=(CH2)2PPh2, (CH2)3C5H4N, (CH2)3CN, (CH2)2Ph, (CH2)2SPh, CH=CH2 and CH2CH=CH2] have been reacted with metal halide and-carbonyl moieties in order to determine the coordination preferences of materials being used as models for metallated longchain linear functionalised polysiloxanes. The products [Me3SiOSiMe(R)OSiMe3]3MLn [R=(CH2)2PPh2, MLn=RhCl],cis-[Me3SiOSiMe(R)OSiMe3]2MLn [R=(CH2)2PPh2 or (CH2)3C5H4N, MLn=Mo(CO)4],trans-[Me3SiOSiMe(R)OSiMe3]2MLn[R=(CH2)2PPh2, MLn=NiCl2, PdCl2, PtCl2 and [Rh(CO)Cl] and [Me3SiOSiMe(R)OSiMe3]MLn [R=(CH2)2PPh2, MLn=Mo(CO)3(2,2-bipyridine); R=(CH2)2Ph, MLn=Mo(CO)3; R=(CH2)3C5H4N, (CH2)3CN, or (CH2)2SPh, MLn=Rh(CO)2Cl; R=CH=CH2 or CH2CH=CH2, MLn=Fe(CO)4] have been isolated and characterised spectroscopically in the course of these studies.  相似文献   

10.
The triphenylsiloxy-substituted cyclotriphosphazenes, N3P3Cl5OSiPh3, gem-N3P3Cl4(OSiPh3)2, N3P3(OSiPh3)6, and N3P3(OPh)5OSiPh3, have been prepared. The synthesis of gem-N3P3Cl4(OSiPh3)2 involves the reaction of (NPCl2)3 with Ph3SiONa to form the intermediates gem-N3P3Cl4(OSiPh3)2(ONa) and gem-N3P3Cl4(ONa)2, which yield gem-N3P3Cl4(OSiPh3)2 when treated with Ph3SiCl. The compounds N3P3Cl5OSiPh3 and N3P3(OSiPh3)0 are formed by the condensation reactions of N3P3Cl5OBun and N3P3(OBun)6, respectively, with Ph3SiCl. The compound N3P3(OPh)5OSiPh3 is synthesized by the reaction between N3P3(OPh)5Cl and Et3SiONa to first give the intermediate N3P3(OPh)5ONa, which yields N3P3(OPh)5OSiPh3 when reacted with Ph3SiCl. The structural characterization and properties of these compounds are discussed. The crystal and molecular structure of gem-N3P3Cl4(OSiPh3)2 has been investigated by single-crystal X-ray diffraction techniques. The crystals are monoclinic with the space group P21/c with a = 16.850(8), b = 12.829(4), c = 18.505(15) Å, and β = 101.00(6)° with V = 3927 Å3 and Z = 4. © 1996 John Wiley & Sons, Inc.  相似文献   

11.
By reaction of pentafluorophenylhydrazine with metal chlorides the complexes M(NH2NHC6F5)4Cl2 (M = Co, Ni), M(NH2NHC6F5)2Cl2 (M = Mn, Fe, Pd, Zn, Cd), Cu(NH2NHC6F5)Cl, and Hg(NH2NHC6F5)2Cl were obtained. From Cr(CO)6 and pentafluorophenylhydrazine the complex Cr(CO)5(NH2NHC6F5) was synthesized.  相似文献   

12.
N,N-Dimethylneopentylamine reacts with Pd(MeCO2)2 to give a novel trinuclear cyclopalladated complex [Me2NCH2CMe2CH2Pd(μ-MeCO2)2Pd(μ-MeCO2)2PdCH2CMe2CH2NMe2]?-0.5C6H6 (I). The reaction of I with PPh3 affords both trans-[Pd(MeCO2)2(PPh3)2] (II) and [Pd(CH2CMe2CH2NMe2)(MeCO2)(PPh3)] (III). The reaction of III with LiCl yields a mononuclear cyclopalladated complex, [Pd(CH2CMe2CH2NMe2)Cl(PPh3)] (IV).  相似文献   

13.
The topological types of suprapolyhedral clusters composed of i-B12 icosahedra have been modeled. The models of icosahedral supraclusters have been used in analysis of the crystal structures of boron and borides (the TOPOS program package). To identify nanocluster precursors in crystal structures, there have been used special algorithms for partitioning structural graphs into disjoint substructures and constructing a basis 3D network of the structure as a graph with the nodes corresponding to the positions of the centroids of the cluster precursors. The cluster self-assembly have been modeled for 25 types of icosahedral framework structures of boron—B12-hR 12, (B12)2(B2)2-oP 28, (B12)4B2-P50, B196-tP 196, and B333-hR 333; binary borides—(B12)O2-hR 14, (B12)P2-hR 14, and (B12)(CBC)-hR 15; templated metal borides—Na2(B12)2B6-oI 64, Mg2(B12)B2-oI 68, Tb(B12)(B4)-mI 60, Al4(B12)4B8-oC 88, (B12)4(Si4)4-oI 64, (B12)4B2Be4-tP 58, Ti2(B12)4B2-tP 52, Sc12B180-tP 192, Cu4Sc12B180-tP 192, Si1.5Sc9B178-tP 216, Mg28B360-oP 388, Al28B352-oP 384, Si28B352-oP 306, Y24(B156)8(B39)8-cF1944, Sc10B315-hR339, and Li24B315-hR336. The symmetry and topology code of the crystal structure self-assembly from nanocluster precursors in the form of primary chain → microlayer → microframework has been completely restored. Frequency analysis of various topological and symmetry pathways for the formation and evolution of cluster precursors makes it possible to elucidate crystal-formation trends in inorganic systems at the microscopic level.  相似文献   

14.
The phase diagrams of four binary systems (C10H21NH3)2CoCl4?(C16H33NH3)2CoCl4, (C12H25NH3)2CoCl4?(C16H33NH3)2CoCl4, (C10H21NH3)2ZnCl4?(C16H33NH3)2ZnCl4 and (C12H25NH3)2ZnCl4?(C16H33NH3)2ZnCl4 were investigated by means of DSC. These six compounds and their binary mixtures can retain energies between 74 and 115 J/g during solid-state transformations at temperatures between 70 and 105°C, and they are therefore being considered for potential use in solar energy systems.  相似文献   

15.
The compound (C5H5)2Fe2(CO)3PPh3, previously obtained by the photolysis of (C5H5)2Fe2(CO)4 with PPh3, may also be obtained by reflluxing these same reactants in benzene. The compound was isolated in pure form by means of low temperature column chromatography. It is unstable in solution in the absence of added PPh3. Solid samples also are unstable over long periods of time. Decomposition in solution is complete within one hour at 80° yielding a mixture of (C5H5)2Fe2(CO)4 and (C5H5)4Fe4(CO)4. This reaction is suppressed by excess PPh3. Heating a mixture of (C5H5)2Fe2(CO)3PPh3 and P(OEt)3 gives a nearly quantitative yield of (C5H5)2Fe2(CO)3P(OEt)3. Refluxing a xylene solution of (C5H5)2Fe2(CO)4 containing a slight molarr excess of PPh3 for 7 h results in the isolation of (C5H5)4Fe4(CO)4 in 56% yield, making this reaction by far the most convenient method for the preparation, in gram quantities, of this transition metal cluster.  相似文献   

16.
Reaction of [WI(CO)27-C7H7)] with dppm (dppm = Ph2PCH2PPh2) or dppe (dppe = Ph2PCH2CH2PPh2) gives the trihaptocycloheptatrienyl complexes [WI(CO)2(L-L)(η3-C7H7)] [L-L = dppm, (A1); L-L = dppe (A2)]. The complex A1 reacts with NH4PF6 to give the unidentate biphosphine complex [W(CO)2(dppm-P)(η7-C7H7)][PF6] (B) which yields [W(CO)(dppm)(η7-C7H7)][PF6] (C) on reaction with Me3NO·2H2O. Substitution of a carbonyl ligand in [W(CO)37-C7H7)][PF6] with the organometallic phosphine ligand [Mo(CO)2(dppe-P)(η7-C7H7)][PF6] yields the heterobimetallic [{W(CO)27-C7H7)}(μ-dppe){Mo(CO)27-C7H7)}x][PF6]2 (D).  相似文献   

17.
Oxidation of lithiodicyclopentadienylrhenium by organic carbonyl compounds gives the complex (C20H20Re2). Spectroscopic data show that this complex consists of two rhenocene fragments, {(C5H)5Re}, linked by a metal-metal bond, and so that it must be represented as a dimer of rhenocene, {(C5H5)Re}2. Reaction of the dimer with benzyl bromide gives {(C5H5)2ReCH2C6H5} and {(C5H52ReBr}, while thermolysis gives the new dimeric complex {(C5H5)2(C5H4)2Re2} and two equivalents of {(C5H5)ReH} and photolysis (λ ? 410 nm) gives [{η4- (C5H6)(C5H5)Re}{η51-(C5H4)(C5H5)Re}].  相似文献   

18.
The modeling of the molecular and electronic structures of the following mono- and biosmium complexes of fullerene C60 was performed by quantum chemical methods (MNDO/PM3 and DFT/PBE): (??2-C60)[Os(PPh3)2(CO)CNMe], (??2,??2-C60)[Os(PPh3)2(CO)(CNMe)]2, (??2-C60)[Os(PH3)2(CO)H], (??2,??2-C60)[Os(PH3)2(CO)H]2, (??2-C60)[Os(PH3)2(CO)CNMe], (??2,??2-C60)[Os(PH3)2(CO)CNMe]2, and (5-C60H5)[Os(C5H5)], (5, 5-C60H10)[Os(C5H5)]2.The osmium atoms in the first six complexes are ??2-coordinated by fullerene C60. In the last two complexes, the ??5-coordination mode is observed. The structures of the radical anions of these complexes were calculated. The energies of the frontier orbitals were evaluated. The acceptor properties of the complexes are discussed. The electron affinities were estimated in two ways: from the energy of the lowest unoccupied molecular orbital (LUMO) and as the energy difference between the neutral molecule and its radical anion.  相似文献   

19.
A 480 L evacuable reaction chamber, equipped with FT-IR spectroscopy on-line and ion chromatography off-line, has been used to study the gas phase reaction between the nitrate radical, NO3, and the reduced organic sulphur compounds CH3CH2SH, (CH3CH2)2S, (CH3CH2)2S2, and CH3CH2SCH3 in air. The products CH3CH2SO3H, SO2, H2SO4, CH3CHO, and CH3CH2ONO2 were identified and quantified in the reactions of the first three compounds, CH3CH2SH, (CH3CH2)2S, and (CH3CH2)2S2. The reaction products were CH3CH2SO3H, CH3SO3H, SO2, H2SO4, CH3CHO, and CH2O in the reaction of CH3CH2SCH3. On the basis of identified reaction products and intermediates observed in the infrared spectra, mechanisms are proposed for the reactions between the NO3 radical and the four reduced organic sulphur compounds. The results of this study, together with those from previous experiments performed in this laboratory on CH3SCH3, CH3SH, and CH3SSCH3 lead to the conclusion that all these species, in the reaction with the NO3 radical, follow a similar degradation mechanism producing SO2, H2SO4, R? SO3H, R? CHO, and R? CH2ONO2, as the main reaction products. The inital step of the reaction of NO3 with R? S? R and R? S? H type (R = CH3, CH2CH3) reduced organic sulphur compounds was found to be H-atom abstraction, probably after the formation of an initial adduct. For the reaction between NO3 and R? S? S? R type compounds, evidence for an addition-decomposition reaction, as the initial steps, was obtained. R? S·, R? S(O)·, and R? S(O)2· appear to be formed as intermediates in all the reactions. © John Wiley & Sons, Inc.  相似文献   

20.
A supramolecular compound of the general formula [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]4 · NH(CH2)4O · C2H4{N(CH2)4O}2 (I) was obtained and examined by X-ray diffraction analysis and thermography. According to X-ray diffraction data, the crystal lattice of compound I shows an unusual alternation of two independent centrosymmetric supramolecular complexes [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]2 · C2H4{N(CH2)4O}2 (Ia) and [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]2 · NH(CH2)4O (Ib). Either complex includes two molecules of an adduct of bis(diethyldithiocarbamato)zinc with morpholine and outer-sphere molecules of 1,2-dimorpholinoethane or morpholine. Adduct molecules are structurally nonequivalent in pairs and linked with solvate molecules by hydrogen bonds. The calculated geometries of the zinc polyhedra are intermediate between trigonal bipyramid and tetragonal pyramid. Thermal decomposition of supramolecular compound I proceeds through desorption of the outer-sphere and coordinated organic molecules; in the final step, defragmentation of the dithiocarbamate part gives zinc sulfide.  相似文献   

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