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1.
The thermal decomposition of [Co(NH3)5Cl]Cl2 was studied under non-isothermal conditions, in dynamic air and argon atmospheres. The kinetics of the particular stages of [Co(NH3)5Cl]Cl2 thermal decomposition were evaluated from the dynamic weight loss data by means of the modified Coats-Redfern method. TheD n andR n models were selected as the models best fitting the experimental TG curves. These models suggest that the kinetics and macromechanism of [Co(NH3)5Cl]Cl2 decomposition can be governed by diffusive and/or phase boundary processes. The values of the activation energy,E a, and the pre-exponencial factor,A, of the particular stages of the thermal decomposition were calculated.  相似文献   

2.
Summary Rate constants are reported for mercury(II)-catalysed aquation of thetrans-[Rh(en)2Cl2]+, [Cr(NH3)5Cl]2+, andcis-[Cr(NH3)4(OH2)Cl]2+ cations in water and in methanol-, ethanol-, and acetonitrile-water solvent mixtures. In the case oftrans-[Rh(en)2Cl2]+, the dependence of rate constants on mercury(II) concentration indicates reaction through a binuclear (Rh-Cl-Hg bridged) intermediate. The dependence of the equilibrium constant for the formation of this intermediate and of its rate constant for dissociation (loss of HgCl+) on solvent composition have been established. With the aid of measured solubilities, published ancillary thermodynamic data, and suitable extrathermodynamic assumptions, the observed reactivity trends for these mercury(II)-catalysed aquations are dissected into initial state and transition state components. The reactivity patterns for these three complexes are compared with those for mercury(II)-catalysed aquation of other chloro-transition metal complexes, particularlycis-[Rh(en)2Cl2]+, [Co(NH3)5Cl]2+, and [ReCl6]2–.  相似文献   

3.
Metal Ampoules as Mini‐Autoclaves: Syntheses and Crystal Structures of [Al(NH3)4Cl2][Al(NH3)2Cl4] and (NH4)2[Al(NH3)4Cl2][Al(NH3)2Cl4]Cl2 The salts [Al(NH3)4Cl2]+[Al(NH3)2Cl4]≡AlCl3 · 3 NH3 ( 1 ) and (NH4+)2[Al(NH3)4Cl2]+[Al(NH3)2Cl4](Cl)2≡ AlCl3 · 3 NH3 · (NH4)Cl ( 2 ) have been obtained as single crystals during the reactions of aluminum and aluminum trichloride, respectively, with ammonium chloride in sealed Monel metal containers. The crystal structure of 1 was determined again [triclinic, P‐1; a = 574.16(10); b = 655.67(12); c = 954.80(16) pm; α = 86.41(2); β = 87.16(2); γ = 84.89(2)°], that of 2 for the first time [monoclinic, I2/m; a = 657.74(12); b = 1103.01(14); c = 1358.1(3) pm; β = 103.24(2)°].  相似文献   

4.
The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 and [Ni(NH3)6]Cl2 Crystals of yellow [V(NH3)6]I2 and green [Cr(NH3)6]I2 were obtained by the reaction of VI2 and CrI2 with liquid ammonia at room temperature. Colourless crystals of [Mn(NH3)6]Cl2 were obtained from Mn and NH4Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH3)6]Cl2 and [Fe(NH3)6]Br2 were obtained by the reaction of FeCl2 and FeBr2 with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH3)6]Br2 were obtained from [Co2(NH2)3(NH3)6]Br3. Purple crystals of [Ni(NH3)6]Cl2 were obtained by the reaction of NiCl2 · 6H2O and NH4Cl with aqueous NH3 solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K2[PtCl6] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.  相似文献   

5.
《Analytical letters》2012,45(12):2182-2193
K[Pt(NH3)Cl3], a valuable precursor for the preparation of platinum complexes with cytostatic activity, e.g. satraplatin, picoplatin, LA-12 and cycloplatam, is currently prepared from cis-[Pt(NH3)2Cl2] or K2[PtCl4] and these are the usual impurities in the final product. A simple, selective and sensitive HPLC-UV analytical method for the determination of the purity of K[Pt(NH3)Cl3] and the quantification of the impurities has been developed and validated. The platinum complexes present in the final product were separated on a strong base ion exchange column by the gradient elution with detection at 213 nm. Intra-assay precisions for the platinum complexes respective to their ions ([PtCl4]2?, [Pt(NH3)Cl3]? and cis-[Pt(NH3)2Cl2]) were between 0.1 and 2.0% (relative standard deviation); intermediate precisions were between 1.4 and 2.0% and accuracies were between 98.6 and 101.4%. Limits of detection of [PtCl4]2?, [Pt(NH3)Cl3]? and cis-[Pt(NH3)2Cl2] were 6 µg · ml?1, 13 mg · ml?1 and 5 µg · ml?1 respectively, limits of quantification of [PtCl4]2?, [Pt(NH3)Cl3]? and cis-[Pt(NH3)2Cl2] were 51 µg · ml?1, 55 mg · ml?1 and 20 µg · ml?1 respectively.  相似文献   

6.
The reaction between [RuNO(NH3)2(NO2)2OH] and an excess of 3 M HCl leads to denitration of the starting complex and precipitation of [Ru(NO)(NH3)2Cl3]. Crystals of the tittle complex have been obtained by evaporation of the mother liquor at ambient temperature. The crystal structure of the product has been determined. The linear nitroso group and a water molecule are coordinated in the trans positions, three nitrogen atoms from NO and NH3 ligands occupy the coordination octahedron face.  相似文献   

7.
Preparation and Crystal Structure of (NH4)2[V(NH3)Cl5]. The Crystal Chemistry of the Compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2, and M2VXCl5 with M = K, NH4, Rb, Cs and X ? Cl, O (NH4)2[V(NH3)Cl5] crystallizes like [Rh(NH3)5Cl]Cl2 in the orthorhombic space group Pnma with Z = 4. The compounds are built up by isolated NH4+ or Cl? and complex MX5Y ions. The following distances have been observed: V? N: 213.8, V? Cl: 235.8–239.1, Rh? N: 207.1–208.5, Rh? Cl: 235.5 pm. Both structures differ from the K2PtCl6 type mainly in the ordering of the MX5Y polyhedra. The compounds M2VCl6 and M2VOCl5 with M = K, NH4, Rb, and Cs crystallize with exception of the orthorhombic K2VOCl5 in the K2PtCl6 type. The ordering of the MX5Y polyhedra in the compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2 and K2VOCl5 enables a closer packing.  相似文献   

8.
Precipitation of PdII as [Pd(NH3)2Cl2] and the Behaviour of Various Impurities The dependence of [Pd(NH3)2Cl2] precipitation upon reaction conditions (pH, Cl? content, reaction time, temperature) has been studied. The dependence of residual Pd content in the mother liquor upon these parameters was found to be significant only for the precipitation temperature (cPd at 20°C: 1.65 ± 0.11 mM; at 50°C: 6.70 ± 0.58 mM). The increase of Pd concentration was due to the formation of Pd(NH3)Cl3?. Among the impurities studied Cr, Ru, and Au were largely precipitated in the NH3 medium. In subsequent precipitation of [Pd(NH3)2Cl2] the following order of coprecipitation was found: The first four elements could be separated only incompletely by repeated reprecipitation. The coprecipitation of the platinum-group metals and of Au was highly dependence upon preceding formation of ammine complexes of these elements. The considerable coprecipitation of PtIV is presumably due to the formation of mixed Pd/Pt compounds, whereas the other impurities are adsorbed by [Pd(NH3)2Cl2].  相似文献   

9.
The reaction of trans-[RuNO(NH3)4(OH)]Cl2 with nitric acid has been studied. Reaction products have been identified by IR spectroscopy, NMR, mass spectrometry, powder and single-crystal X-ray diffraction, and chemical analysis. Synthesis methods have been developed for amminenitrosoruthenium complexes containing outer-sphere and coordinated nitrate ions: trans-[RuNO(NH3)4(H2O)](NO3)3 (I), trans-[RuNO(NH3)4(NO3)](NO3)2 (II), and fac-[RuNO(NH3)2(NO3)3] (III). Complex II has two polymorphs: monoclinic and tetragonal. The latter has been studied by X-ray crystallography.  相似文献   

10.
Sodium thiosulfate has been utilized as a rescuing agent for relief of the toxic effects of cisplatin and carboplatin. In this work, we characterized the kinetics of reactions of the trans-dichloro-platinum(IV) complexes cis-[Pt(NH3)2Cl4], ormaplatin [Pt(dach)Cl4] and trans-[PtCl2(CN)4]2? (anticancer prodrugs and a model compound) with thiosulfate at biologically important pH. An overall second-order rate law was established for the reduction of trans-[PtCl2(CN)4]2? by thiosulfate, and varying the pH from 4.45 to 7.90 had virtually no influence on the reaction rate. In the reactions of thiosulfate with cis-[Pt(NH3)2Cl4] and with [Pt(dach)Cl4], the kinetic traces displayed a fast reduction step followed by a slow substitution involving the intermediate Pt(II) complexes. The reduction step also followed second-order kinetics. Reductions of cis-[Pt(NH3)2Cl4] and [Pt(dach)Cl4] by thiosulfate proceeded with similar rates, presumably due to their similar configurations, whereas the reduction of trans-[PtCl2(CN)4]2? was about 1,000 times faster. A common reduction mechanism is suggested, and the transition state for the rate-determining step has been delineated. The activation parameters are consistent with transfer of Cl+ from the platinum(IV) center to the attacking thiosulfate in the rate-determining step.  相似文献   

11.
Ni(NH3)Cl2 and Ni(NH3)Br2 were prepared by the reaction of Ni(NH3)2X2 with NiX2 at 350 °C in a steel autoclave. The crystal structures were determined by X‐ray powder diffraction using synchrotron radiation and refined by Rietveld methods. Ni(NH3)Cl2 and Ni(NH3)Br2 are isotypic and crystallize in the space group I2/m with Z = 8 and for Ni(NH3)Cl2: a = 14.8976(3) Å, b = 3.56251(6) Å, c = 13.9229(3) Å, β = 106.301(1)°; Ni(NH3)Br2a = 15.5764(1) Å, b = 3.74346(3) Å, c = 14.4224(1) Å, β = 105.894(1)°. The crystal structures are built up by two crystallographically distinct but chemically mostly equivalent polymeric octahedra double chains [NiX3/3X2/2(NH3)] (X = Cl, Br) running along the short b‐axis. The octahedra NiX5NH3 share common edges therein. The crystal structures of the ammines Ni(NH3)mX2 with m = 1, 2, 6 can be derived from that of the halides NiX2 (X = Cl, Br) by successive fragmentation of its CdCl2 like layers by NH3.  相似文献   

12.
Simultaneous TG-DTG-DTA studies on [Co(NH3)5Cl]Cl2 under non-isothermal conditions were carried out in dynamic air and argon atmospheres in the temperature range 293–1273 K. Thermogravimetric measurements under quasi-isothermal conditions were also made. On the basis of the experimental data (weight loss, X-ray diffraction, reflectance spectroscopy and chemical analysis), the probable decomposition sequences are presented. The data indicate that the thermal decomposition of [Co(NH3)5Cl]Cl2 occurs in three stages in argon and four stages in air.The changes in the morphology of crystalline [Co(NH3)5Cl]Cl2 powder in the course of its thermal decomposition in air were followed by scanning electron microscopy.
Zusammenfassung In dynamischer Luft- und ArgonatmosphÄre wurden im Temperaturbereich 293–1273 K unter nichtisothermen Bedingungen simultane TG-DTG-DTA Untersuchungen an [Co(NH3)5Cl]Cl2 durchgeführt, ebenso auch thermogravimetrische Untersuchungen unter quasi-isothermen Bedingungen. Auf der Grundlage der experimentellen Daten (Gewichtsverlust, Röntgendiffraktion, Reflexionsspektroskopie und chemische Analyse) wurde eine wahrscheinliche Zersetzungssequenz erstellt. Es zeigte sich, da\ die thermische Zersetzung in Argon in drei Schritten, in Luft dagegen in vier Schritten verlÄuftDie VerÄnderung der Morphologie kristallinen [Co(NH3)5Cl]Cl2-Pulvers im Verlaufe seiner thermischen Zersetzung in Luft wurde durch Scanning-Elektronenmikroskopie verfolgt.
  相似文献   

13.
Kinetic parameters (apparent activation energy, reaction order, pre-exponential factor (Z) in the Arrhenius equation) for thermal decomposition of the [Co(NH3)6]Cl3, Co[(NH3)4Cl2]Cl, K3[Fe(C2O4)3]3H2O and Fe(CH3COO)3 are reported. They have been calculated on the DTA and TG data according to Coats-Redfern's model. Both, decomposition data obtained in argon and in air atmosphere have been considered and the results are compared.
Zusammenfassung Es werden die kinetischen Parameter (scheinbare Aktivierungsenergie, Reaktionsordnung, prÄexponentieller Faktor (Z) der Arrhenius-Gleichung) der thermischen Zersetzung von [Co(NH3)6]Cl3, [Co(NH3)4Cl2]Cl, K3[Fe(C2O4)3]3H2O und Fe(CH3COO)3 beschrieben, die entsprechend dem Coats-Redfern-Modell auf der Basis der DTA- und TG-Daten errechnet wurden. Die Zersetzung wurde sowohl in Argon als auch in Luft durchgeführt und die erhaltenen Daten miteinander verglichen.


Helpful comments from Professor W. Wojciechowski and financial support from Institute for Low Temperatures and Structure Research Polish Academy of Sciences (CPBP 01.12) are greatefully acknowledged.  相似文献   

14.
Physicochemical study of cis-[Pt(NH3)2Cl2] and cis-[Pt(NH3)2Cl2(OH)2] is carried out, and immobilization of platinum complexes on the nanoporous carbon substrate is investigated. The solubility of cis-[Pt(NH3)2Cl2] in 1 M HCl solution is determined, and the average enthalpy of dissolution is calculated: ΔsolH° = 27.3 ± 0.9 kJ/mol. The batch capacity is determined experimentally for cis-[Pt(NH3)2Cl2] and cis- [Pt(NH3)2Cl2(OH)2] to be 32.9 mg/g (0.17 mg-equiv/g) and 47.6 mg/g (0.24 mg-equiv/g), respectively. Immobilization of platinum complexes on the oxidized carbon surface is found to take place due to interaction between carboxy groups and ammine groups of platinum complexes. The resulting heat capacity curves are used to calculate the enthalpies of adsorption for cis-[Pt(NH3)2Cl2] and cis-[Pt(NH3)2Cl2(OH)2] on the oxidized carbon surface, equal to 24.46 and 27.46 kJ/mol, respectively.  相似文献   

15.
Binary complex salts of M(NH3)5Cl]2[IrCl6]Cl2 composition, where M = Co(III), Rh(III), or Ir(III), have been studied. All phases are isostructural with [M(NH3)5Cl]2[PtCl6]Cl2 complexes [M = Rh(III) and Ir(III)]; Xray structural and crystallochemical analysis have been performed.  相似文献   

16.
Summary The ammoniation ofcis-[Rh(en)2Cl2] · (ClO4) in liquid NH3 was studied at constant ionic medium of 0.20 m perchlorate in the 0 to 35° range. The complex reacts in two distinct steps to givecis-[Rh(en)2(NH3)2] · (ClO4)3, with the intermediate formation ofcis-[Rh(en)2(NH3)Cl] · (ClO4)2. Both steps follow a conjugate-base mechanism. Activation parameters were obtained for the acid-base preequilibrium and the rate-determining step. The entropies of activation for the rate-determining step are 0 and –42 JK–1mol–1 for the first and second ammoniations respectively. These values are considerably lower than those found for the cobalt(III) analogues. The entropy changes for the acid-base equilibria are –84 and –36 JK–1mol–1 respectively, which is less negative than those values found for the cobalt(III) analogues. Trans-[Rh(en)2I2] · (ClO4) ammoniates totrans-[Rh(en)2(NH3)I] · (ClO4)2. The contribution of spontaneous ammoniation to the overall reaction oftrans-[Rh(en)2I2] · (ClO4) is negligible, so the uniqueness oftrans-[Co(en)2Cl2] · (ClO4) among cobalt(III) complexes in this respect is not reproduced for thetrans-dihalotetraamine structure in rhodium(III) complexes. A comparison of cobalt(III) and rhodium(III) amines with respect to activation parameters and the influence of formal charge of the metal complex on reactivity indicates a more associative type of activation for rhodium(III).  相似文献   

17.
Trans-[Cr(NH3)4(H2O)Cl]Cl2 (A) crystallizes in the monoclinic space group P21/m (No. 11) with a = 6.556(1), b = 10.630(5), c = 6.729(2) Å and β = 96.15(3)°. Trans-[Cr(NH3)4Cl2]I (B) has monoclinic C2/m (No. 12) space group and a = 9.877(2), b = 8.497(2), c = 6.047(2) Å and β = 108.98(2)°. Both unit cells contain two formula units. Cr? Cl, Cr? O(H2O) and three independent Cr? N(NH3) distances for A are 2.98(1), 2.023(2), 2.067(2), 2.086(3) and 2.064(3) °. Cr? Cl and Cr? N(NH3) bonds in B are 2.325(1) and 2.071(2) °. All octahedral angles are close to 90 and 180°. Both structures were refined to very low R values. Water molecule from trans-[Cr(NH3)4(H2O)Cl]2+ is hydrogen bonded to both ionic chlorides. Cation and two anions form the motive which repeats itself in the crystal. Cations and anions of the second structure are distributed in layers. Each cation and anion have coordination number eight.  相似文献   

18.
The nucleophilic substitution reaction under NH3 chemical ionization (CI) conditions in cis- and trans-1,2-dihydroxybenzosuberans (1–4) has been studied with the help of ND3 CI and metastable data. The results indicate that in the parent diols 1 (cis) and 2 (trans), the substitution ion [MsH]+, is produced mainly by the loss of H2O from the [MNH4]+ ion (SNi reaction) while in their 7-methoxy derivatives 3 and 4, the ion-molecule reaction between [M? OH]+ and NH3 seems to be the major pathway for the formation of [MsH]+. The substitution ion from 1 and 2 and the [MH]+ ion from trans-1-amino-2-hydroxybenzosuberan give similar collision-induced dissociation mass-analysed ion kinetic energy spectra. Interestingly, their diacetates do not undergo the substitution reaction.  相似文献   

19.
Two New Ammoniates of Scandium Trichloride, ScCl3(NH3) and ScCl3(NH3)2 Reactions of scandium with ammonium chloride in the presence of cupric chloride in sealed copper ampoules yield colorless single crystals of the two new ammoniates of scandium trichloride, ScCl3(NH3) und ScCl3(NH3)2. The crystal structures were determined from single crystal data; they both crystallize with the triclinic crystal system. In ScCl3(NH3)2 isolated unsymmetrical dimers of double octahedra, according to [Sc‐mer‐(NH3)3/1Cl1/1Cl(2/2)×2Sc(NH3)1/1Cl3/1] are the characteristic structural features. The crystal structure of ScCl3(NH3) also contains double octahedra, [Sc(NH3)2/1Cl2/1Cl2/2]2; these dimers are, however, connected via common edges forming infinite zig‐zag chains according to the formulation [Sc(NH3)1/1Cl1/1Cl4/2].  相似文献   

20.
The preparations of cis- and trans-[PtH(C6Cl5)(PEt3)2] by thermal decomposition of cis- and trans-[Pt(OCHO)(C6Cl5)(PEt3)2], respectively, are reported. Also described are cis- and trans-[Pt(SnCl3)(C6Cl5)(PEt3)2], obtained by treating SnCl2 with cis- and trans-[PtCl(C6,Cl5)(PEt3)2], respectively. It is shown that while trans- [PtH(C6Cl5)(PEt3)2] does not form hydride-bridged complexes in the presence of trans-(PtH(MeOH)(PEt3)2]+, the corresponding complex trans-[PtH(C6)(PEt3)2] reacts with the same solvento complex, in methanol, giving labile [(PEt3)2HPt(-μH)Pt(C6F5)(PEt3)2]+.  相似文献   

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