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1.
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   

2.
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   

3.
Os(η2-CH2O)(CO)2(PPh3)2 reacts with CSe2 to form a metallacycle Os(CH2OC[Se]Se)(CO)2(PPh3)2. This compound breaks down to Os(η2-CH2Se)(CO)2(PPh3)2 with probable loss of COSe. An alternative route to Os(η2-CH2Se)(CO)2(PPh3)2 and also Os(η2-CH2Te)(CO)2(PPh3)2 is through reaction of Os(CH2I)I(CO)2(PPh3)2 with SeH? and TeH?, respectively. HCl with Os(η2-CH2E)(CO)2(PPh3)2 (E = Se or Te) gives OsCl(EMe)(CO)2(PPh3)2 while methyl iodide gives [Os(η2-CH2EMe)(CO)2 - (PPh3)2] I. BH4? reacts with these cations to cleave the CE bond and form Os(CH3)(EMe)(CO)2(PPh3)2.  相似文献   

4.
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   

5.
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   

6.
The thermal stability and the solid-state thermal decomposition of the known mononuclear cobalt(II) and nickel(II) complexes [H2N(C5H3N)N(H)C(Me)=NH]M(OOCBut)2, [(NH2)2C6H2Me2]3M(OOCBut)2 and the new compounds L2M(OOCBut)2 (L = = (2-NH2)C5H3N, (2-NH2)(6-Me)C5H3N), and [(2,6-NH2)2C5H3N]2Ni(OOCBut)2 were studied by differential scanning calorimetry and thermogravimetric analysis. Efficient methods were developed for the synthesis of these complexes. The mononuclear complexes are thermally quite stable. The thermal stability of the complexes depends on the nature of the ligand and decreases in the series (2,6-NH2)2C5H3N > H2N(C5H3N)NHC(Me)=NH > (NH2)2C6H2Me2 > (2-NH2)C5H3N > (2-NH2)(6-Me)C5H3N. The nickel(II) complexes are thermally more stable than the related cobalt(II) complexes. The thermolysis (<500 °C) of Co and Ni pivalates is a destructive process. The phase composition of the decomposition products is determined by the nature of metal and coordinated ligands.  相似文献   

7.
Comparative analysis of catalytic activity of substituted bis(cyclopentadienyl)zirconium dichlorides with the general formula (R n Cp)2ZrCl2 (Cp2ZrCl2, (MeCp)2ZrCl2, (PriCp)2ZrCl2, (Pri 2Cp)2ZrCl2, (BunCp)2ZrCl2, (BuiCp)2ZrCl2, (ButCp)2ZrCl2, Cp* 2ZrCl2 (Cp*=Me5C5), (Me3SiCp)2ZrCl2, (cyclo-C6H11Cp)2ZrCl2, and [(cyclo-C6H11)2Cp]2ZrCl2) in ethene polymerization using polymethylalumoxane as the cocatalyst was performed. The molecular mass characteristics of the polyethylene samples obtained were determined. A linear correlation of the specific activity of the catalysts and the turnover number with the electronic and steric characteristics of substituents at the Cp ring of the complexes was established for the first time. Analysis of the polymerization kinetics and the obtained correlation between the specific activity of the complexes and molecular mass characteristics of the polyethylene samples suggest that alkyl substituents participate in reactions responsible for the restriction of the polymer chain growth and regeneration of the active center. These interactions most likely involve associates of AlMe3 with polymethylalumoxane molecules.  相似文献   

8.
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   

9.
The heat of formation of benzophenone oxide, Ph2CO2, was measured using photoacoustic calorimetry. The enthalpy of the reaction Ph2CN2 + O2 → Ph2CO2 + N2 was found to be ?48.0 ±0.8 kcal mol?1 and ΔHf(Ph2CN2) was determined by measuring the reaction enthalpy for Ph2CN2 + EtOH → Ph2CHOEt + N2 (?53.6 ±1.0 kcal mol?1). Taking ΔHf(PhCHOEt) = ?10.6 kcal mol?1 led to ΔHf(Ph2CN2) = 99.2 ± 1.5 kcal mol?1 and hence to ΔHf(Ph2CO2) = 51.1 ± 2.0 kcal mol?1. The results imply that the self-reaction of benzophenone oxide i.e., 2Ph2CO2 → 2Ph2CO + O2 is exothermic by ?76.0 ±4.0 kcal mol?1.  相似文献   

10.
The reactions of ionized di-n-butyl ether are reported and compared with those of ionized n-butyl sec-butyl and di-sec-butyl ether. The main fragmentation of metastable (CH3CH2CH2CH2)2O+. is C2H5? loss (?85%), but minor amounts (2–4%) of CH3?, C4H7?, C4H9?, C4H10 and C4H10O are also eliminated. In contrast, C2H5? elimination is of much lower abundance (20 and 4%, respectively) from metastable CH3CH2CH2CH2OCH(CH3)CH2CH3+. and [CH3CH2(CH3)CH]2O+., which expel mainly C2H6 and CH3? (35–55%). Studies on collisional activation spectra of the C6H13O+ oxonium ions reveal that C2H5? loss from (CH3CH2CH2CH2)2O+. gives the same product, (CH3CH2CH2CH2 +O?CHCH3) as that formed by direct cleavage of CH3CH2CH2CH2OCH(CH3)CH2CH3+.. Elimination of C2H5? from (CH3CH2CH2CH2)2O+. is interpreted by means of a mechanism in which a 1,4-H shift to the oxygen atom initiates a unidirectional skeletal rearrangement to CH3CH2CH2CH2OCH(CH3)CH2CH3+., which then undergoes cleavage to CH3CH2CH2CH2+O?CHCH3 and C2H5?. Further support for this mechanism is obtained from considering the collisional activation and neutralization-reionization mass spectra of the (C4H9)2O+. species and the behaviour of labelled analogues of (CH3CH2CH2CH2)2O+.. The rate of ethyl radical loss is suppressed relative to those of alternative dissociations by deuteriation at the γ-position of either or both butyl substituents. Moreover, C2H5? loss via skeletal rearrangement and fragmentation of the unlabelled butyl group in CH3CH2CH2CH2OCH2CH2CD2CH3+. occurs approximately five times more rapidly than C2H4D? expulsion via isomerization and fission of the labelled butyl substituent. These findings indicate that the initial 1,4-hydrogen shift is influenced by a significant isotope effect, as would be expected if this step is rate limiting in ethyl radical loss.  相似文献   

11.
Organotin derivatives of dimethyldithioarsinic (dithocacodylic) acid have been obtained from the appropriate organotin chloride and the sodium salt of the latter. Tin(IV) chloride and NaS2AsMe2 · 2 H2O yielded only two products, namely Cl2Sn(S2AsMe2)2 and Sn (S2AsMe2)4, regardless of the reagent ratio. Spectroscopic characterization of the compounds (infrared and1H NMR) provides structural information suggesting that the dimethyldithioarsinato group behaves as monodentate (or anisobidentate) ligand in Me2Sn(S2AsMe2)2, Bu2Sn-(S2AsMe2)2 and Cy3Sn(S2AsMe2), as bidentate in Ph2Sn(S2AsMe2)2, Ph3Sn(S2AsMe2) and Cl2As(S2AsMe2)2, whereas Sn(S2AsMe2)4 contains both mono- and bidentate ligands, presumably in a six-coordinate structure.  相似文献   

12.
The solubilities of the systems CeO2-SeO2-H2O and Ce2O3-SeO2-H2O were studied at 100°C. The field of crystallization of Ce(SeO3)2 was established in the system CeO2-SeO2-H2O, and fields of crystallization of Ce2(SeO3)3 and Ce2(SeO3)3H2SeO3 were established in the system Ce2O3-SeO2-H2O. The compound obtained were identified by means of chemical, X-ray and derivatograph analysis. The mechanism of thermal dissociation of Ce(SeO3)2, Ce2(SeO3)3 and Ce2(SeO3)3·H2SeO3 was studied. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
The electrochemical fluorination of chlorine-containing alkylamines has been studied. It was found that, in general, the carbon-chlorine bond in the alkylamines is retained during electrochemical fluorination is anhydrous hydrogen fluoride, yielding chlorine-containing polyfluoroalkylamines. Perfluoroalkylamines and fluorocarbons were also produced.By the use of this method, several new chloropolyfluoroamines such as (CF3)2NCF2CClF2, (C2F5)2NCF2CClF2, (CF3)(C2F5)NCF2CClF2, (CClF2CF2)2NCF3, (CClF2CF2)2NC2F5, (C2F5)(CClF2CF2)NF, (CClF2CF2)2NF, (CF3)2NCF2CF2CClF2, CF2(CF2)3NCF2CClF2, and CF2CF2OC2F4NCF2CClF2 have been isolated and characterized.  相似文献   

14.
The reaction mechanism of the halogen (Cl and Br)-atom initiated oxidation of C2H4 was studied using the long path FTIR spectroscopic method in 700 torr of air at 296 ± 2 K. Among the major halogen-containing products were X? CH2CHO, X? CH2CH2OH, and X? CH2CH2OOH (X = Cl or Br) which were shown to be formed via the self-reaction of the X? CH2CH2OO radicals, i.e., 2X? CH2CH2OO → 2X? CH2CH2O + O2; (a) 2X? CH2CH2OO → X? CH2CHO + X? CH2CH2OH + O2 and (b) followed by X? CH2CH2O + O2 → X? CH2CHO + HO2 and X? CH2CH2OO + HO2 → X? CH2CH2OOH + O2. From the observed yields of X? CH2CHO and X? CH2CH2OH the branching ratios for reactions (a) and (b) were determined to be ka/kb = 1.35 ± 0.07(2σ) for both X = Cl and Br. In addition, the O2-dependence of the rate constant for the Br + C2H4 reaction was determined by the relative rate technique as a function of O2 partial pressure from 140 to 700 torr at 700 torr total pressure of N2/O2 diluent. Rate constants for the reactions of Cl-atoms with Cl-CH2CHO and Br-atoms with Br-CH2CHO were also determined to be [4.3 ± 0.2(2sigma;)] × 10?11 and less than or equal to [1.83 ± 0.11(2σ)] × 10?13 cm3 molecule?1 s?1, respectively.  相似文献   

15.
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   

16.
The mass spectra of the following acetylenic derivatives of Co2(CO)8 are reported: Co2(CO)6C2H2Co2(CO)6C 2,(CH3)2, Co2(CO)6 C2(CH2Cl)2, Co2(CO)6C2 (CF3)2, Co2(CO)2C2(C6H5)2 and Co2(CO)6C2(COOCH3)2. The effect of different C2RR′ on fragmentation modes is investigated. When R and R′ are aromatic groups, the major controlling factor is the stability of charged fragments; in other cases, it seems to be the loss of a stable neutral moiety. Transfer processes of alkoxylic groups are observed in Co2(CO)6C2(COOCH3)2, as well as in Co3(CO),9CCOOCH3, and Co3(CO)9CCOOC2H5. It is suggested that both cobalt and carbon atoms may be the migration sites.  相似文献   

17.
The thermal properties of some hydrazidocarbonates of copper, Cu(N2H3COO)2.0.5H2O, nickel, Ni(N2H3COO)2.2N2H4, and iron, Fe(N2H3COO)2 and N2H5[Fe(N2H3COO)3].H2O, were studied in an inert argon atmosphere. The TG, DTG and DSC curves for these compounds were taken. In the case of N2H5[Fe(N2H3COO)3].H2O, intermediates were observed and isolated during the decomposition. The end-products were metal powders oxidized to a greater or lesser degree.
Zusammenfassung In einer inerten Argonatmosphäre wurden die thermischen Eigenschaften einiger Hydrazidocarbonate von Kupfer, Cu(N2H3COO)2.0.5H2O, Nickel Ni(N2H3COO)2.2N2H4 und Eisen Fe(N2H3COO)2 bzw. N2H5[Fe(N2H3COO)3].H2O ermittelt, d.h. TG-, DTG- und DSC-Kurven wurden angefertigt. Im Falle von N2H5[Fe(N2H3COO)3].H2O konnten während der Zersetzung auch Zwischenprodukte beobachtet und isoliert werden. Die Endprodukte waren mehr oder weniger oxydierte Metallpulver.


Paper presented at the 6th World Conference for Thermal Analysis, Capri, 1989.

This work was supported by the Research Council of Slovenia.  相似文献   

18.
Reactions of CrO2F2 with MF or MF2 gave the corresponding M2CrO2F4 and MCrO2F4 fluorochromates. With the Lewis Acids (SO3, TaF5, SbF5) and (CF3CO)2O known and new chromyl compounds [CrO2(CF3COO)2, CrO2(SO3F)2, CrO2FTaF6, CrO2FSbF6, CrO2FSb2F11] were produced. Chromyl fluoride and inorganic salts (CF3COONa and NaNO3) produced the following complexes - Na2CrO2F2(CF3COO)2 and Na2CrO2F2(NO3)2. Unusual solid products were obtained with CrO2F2 and NO, NO2, SO2.A new method of preparing CrO2F2 is also presented.  相似文献   

19.
One-, two- and three-dimensional CN-bridged metal complex structures made up of building blocks such as linear [Ag(CN)2], square planar [Ni(CN)4]2– or tetrahedral [Cd(CN)4]2–, and of the complementary ligands such as ammonia, water, unidentate amine, bidentate a,w- diaminoalkane, etc., are reviewed with an emphasis on their behaviour as hosts to afford clathrate inclusion compounds with guest molecules and as self-assemblies to form supramolecular structures with or without guests. The historical background is explained for Prussian blue and Hofmann's benzene clathrate based on their single crystal structure determinations. The strategies the author and coworkers have been applying to develop varieties of clathrate inclusion compounds from the Hofmann-type are demonstrated with the features observed for the developed structures determined by single crystal X-ray diffraction methods.Abbreviations for Ligands and Guests mma NMeH2 - dma NMe2H - tma NMe3 - mea NH2(CH2)2OH - en NH2(CH2)2NH2 - pn NH2CHMeCH2NH2 - tn NH2(CH2)3NH2 - dabtn NH2(CH2)4NH2 - daptn NH2(CH2)5NH2 - dahxn NH2(CH2)6NH2 - dahpn NH2(CH2)7NH2 - daotn NH2(CH2)8NH2 - danon NH2(CH2)9NH2 - dadcn NH2(CH2)10NH2 - mtn NMeH(CH2)3NH2 - dmtn NMe2(CH2)3NH2 - detn NEt2(CH2)3NH2 - temtn NMe2(CH2)3NMe2 - dien NH2(CH2)2NH(CH2)2NH2 - pXdam p-C6H4(NH2CH2)2 - rnXdam m-C6H4(NH2CH2)2 - py C5H5N pyridine - ampy NH2C5H4N aminopyridine - Clpy CIC5H4N chloropyridine - Mepy MeC5H4N methylpyridine - dmpy Me2C5H3N dimethylpyridine - bpy NC5H4C5H4N bipyridine - quin C7H9N quinoline - iquin iso-C7H9N isoquinoline - qxln C8H6N2 quinoxaline - Pe C5H11-pentyl imH: C3N2H4 imidazole - pyrz N(CHCH)2N pyrazine - Mequin MeC7H8N methylquinoline - bppn C13H14N2 1,3-bis(4-pyridyl)propane - bpb C14H8N2 1,4-bis(4-pyridyl)butadiyne - N-Meim C3N2H3Me N-methylimidazole - 2-MeimH C3N2H3Me 2-methylimidazole - dmf HOCNMe2 dimethylformamide - hmta C6H12N4 hexamethylenetetramine - o-phen C12H8N2 1,10-phenanthroline - den HN(CH2CH2)2NH piperazine - morph HN(CH2CH2)2O morpholine - ten N(CH2CH2)3N 1,4-diazabicyclo[2.2.2]octane - ameden NH2(CH2)2N(CH2CH2)2NH N-(2-aminoethyl)piperazine Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995.  相似文献   

20.
In dissociation experiments of H2O2 under shock wave conditions, the spectra of H2O2 and HO2 have been observed in the UV at 2200 ≤ 2800 Å. By the use of these spectra the H2O2 decomposition in the presence of H2 and CO at 870 ≤ T ≤ 1000°K has been analyzed. It was found that in this temperature range, in contrast to low temperature behavior, reactions of H atoms with H2O2 and with HO2 are equally important. The rate of the reaction H + H2O2 ← HO2 + H2 was estimated in comparison with the rate of the reaction between H and HO2. Good agreement between calculated and measured concentration profiles of HO2 and H2O2 was obtained.  相似文献   

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