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1.
Emilio Bustelo Isaac de los Ríos Manuel J. Tenorio M. Carmen Puerta Pedro Valerga 《Monatshefte für Chemie / Chemical Monthly》2000,131(12):1311-1320
Summary. The solid-state tautomerization of the hydrido-alkynyl derivatives [Cp
*RuH(C&*CR)-(dippe)][BPh4] (Cp* = C5Me5; R = SiMe3, Ph, H; dippe = 1,2-bis-(diisopropylphosphino)-ethane) to their vinylidene isomers [Cp
*Ru*C*CHR(dippe)][BPh4] was studied by IR spectroscopy. Characteristic isothermic αvs. t curves for each individual rearrangement process were recorded. Their shape, and hence the isomerization mechanism, depends
strongly on the nature of the substituent R. The kinetic analysis of the above curves using the Avrami-Erofeev provided some mechanistic information about the isomerization process in the solid.
Received July 7, 2000. Accepted August 29, 2000 相似文献
2.
A. R. Kudinov D. A. Loginov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1998,47(8):1583-1584
Thirty-electron triple-decker complexes with a central pentaphospholyl ligand [(η-C5Me5)Fe(μ-η:η-P5)M(η-C5R5)]BF4 (M=Fe, R=Me or M=Ru, R=H, Me) were synthesized by a stacking reaction of cationic 12-electron fragments [(η-C5R5)M]+ with (η-C5Me5)Fe(η-P5).
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1625–1626, August, 1998. 相似文献
3.
M. A. Il’in E. V. Kabin V. A. Emel’yanov I. A. Baidina V. A. Vorob’yov 《Journal of Structural Chemistry》2009,50(2):328-334
Methods for the synthesis of trans-diammino complexes [RuNO(NH3)2(NO2)2(OH)] (I) and [RuNO(NH3)2(H2O)(NO3)2](NO3)·H2O (II) are suggested. The compounds were studied by IR spectroscopy and X-ray phase and X-ray structural analyses. Crystal data:
space group P-1; a = 6.2328(2) ?, b = 11.0488(3) ?, c = 11.0981(4) ?, α = 71.942(1)°, β = 83.291(1)°, γ = 86.877(1)° (I); space group P21; a = 6.6290(2) ?, b = 13.4389(5) ?, c = 7.0180(2) ?, β 114.281(1)° (II). Complex II readily lost some part of crystal water on storage in open air.
Original Russian Text Copyright ? 2009 by M. A. Il’in, E. V. Kabin, V. A. Emel’yanov, I. A. Baidina, and V. A. Vorob’yov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 2, pp. 341–348, March–April, 2009. 相似文献
4.
Keiichi Satoh Toshio Suzuki Kiyoshi Sawada 《Monatshefte für Chemie / Chemical Monthly》2001,132(10):1145-1155
Summary. The molecular structures of bis-(pyridine base) complexes of cadmium(II) chloride and bromide, where the pyridine base is pyridine ( py), 3-methylpyridine (3-Me-py), 4-methylpyridine (4-Me-py), and 4-ethylpyridine (4-Et-py), were investigated by means of single-crystal X-ray diffraction and Raman spectroscopy. The crystal structures of CdCl2 py
2 (1), CdCl2(3-Me-py)2 (2), and CdCl2(4-Me-py)2 (3) were determined. All crystals are monoclinic; 1: a = 17.784(2), b = 8.666(1), c = 3.8252(7) ?, β = 91.54(1)°, space group: P21/n; 2: a = 11.89(1), b = 14.41(1), c = 3.874(6) ?, β = 92.3(1)°, space group: P21/a; 3: a = 21.091(2), b = 3.8884(5), c = 18.2317(3) ?, β = 113.64(1)°, space group: C2/c. The structures were refined to R/R
w
values (%) of 3.2/5.5, 3.0/5.0, and 3.4/5.1 for 1–3. All cadmium atoms are octahedrally coordinated with the chloride ions forming infinite di-μ-chloro polymeric linear chains
and the nitrogen atoms of the pyridine base in trans configuration. The Cd chains are oriented along the c-axis in 1 and 2 and along the b-axis in 3. The crystal structures indicate the absence of a peculiar interaction between the polymeric chains. The Raman spectra of eight complexes were measured in the range of 550–50 cm−1, and the Raman peaks originating from cadmium-halogen vibrations were assigned. The Raman spectra of 1 and 2 are quite alike in the lattice mode vibration region. The resemblance of the cadmium-halogen vibration peaks indicates the
same halogenide ion bridged octahedral structure for all complexes.
Received March 27, 2001. Accepted (revised) June 19, 2001 相似文献
5.
A. R. Kudinov D. V. Muratov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1999,48(4):794-795
The first unsymmetrical 34-electron cationic cobalt-nickel triple-decker complex with a central cyclopentadienyl ligand [(η-C6Me6)Co(μ-η:η-C5H5)Ni(η-C5)PF6 was prepared by the reaction of [(η-C6Me6)2Co]PF6 with nickelocene.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 798–799, April, 1999. 相似文献
6.
An O-bonded sulphito complex, Rh(OH2)5(OSO2H)2+, is reversibly formed in the stoppedflow time scale when Rh(OH2)
6
3+
and SO2/HSO
3
−
buffer (1 <pH< 3) are allowed to react. For Rh(OH2)5OH2++ SO2 □ Rh(OH2)5(OSO2H)2+ (k1/k-1), k1 = (2.2 ±0.2) × 103 dm3 mol−1 s−1, k−1 = 0.58 ±0.16 s−1 (25°C,I = 0.5 mol dm−3). The protonated O-sulphito complex is a moderate acid (K
d
= 3 × 10−4 mol dm−3, 25°C, I= 0.5 mol dm−3). This complex undergoes (O, O) chelation by the bound bisulphite withk= 1.4 × 10−3 s−1 (31°C) to Rh(OH2)4(O2SO)+ and the chelated sulphito complex takes up another HSO
3
−
in a fast equilibrium step to yield Rh(OH2)3(O2SO)(OSO2H) which further undergoes intramolecular ligand isomerisation to the S-bonded sulphito complex: Rh(OH2)3(O2SO)(OSO2)- → Rh(OH2)3(O2SO)(SO3)− (k
iso
= 3 × 10−4 s−1, 31°C). A dinuclear (μ-O, O) sulphite-bridged complex, Na4[Rh2(μ-OH)2(OH)2(μ-OS(O)O)(O2SO)(SO3) (OH2)]5H2O with (O, O) chelated and S-bonded sulphites has been isolated and characterized. This complex is sparingly soluble in water
and most organic solvents and very stable to acid-catalysed decomposition 相似文献
7.
The absorption spectra of isoquinoline-iodine or 2,4-lutidine-iodine solutions in organic solventsn-hexane,n-heptane, cyclohexane, carbon tetrachloride, benzene, toluene, chlorobenzene, ando-dichlorobenzene have been measured and interpreted in terms of the D+I2=DI2 equilibrium, where D is isoquinoline or 2,4-lutidine. Values ofK (288–320°K), ΔHo, and ΔSo for the reaction were calculated. A correlation between theK values and the solubility parameter of the solvent (Buchowski's relation) has been found. 相似文献
8.
V. A. Shlyapochnikov L. S. Khaikin O. E. Grikina N. O. Cherskaya L. E. Maksimova N. F. Pyatakov 《Russian Chemical Bulletin》1998,47(11):2173-2176
Vibrational spectra of several nitramines in the long-wave region (50–450 cm−1) were studied. The frequencies of intra- and intermolecular vibrations were separated and a tentative assignment of the frequencies
of self-associative complexes was performed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2241–2244, November, 1998. 相似文献
9.
Summary. The geometries and total energies of several T-shaped platinum(II) complexes of the type (H3P)PtXY (X, Y=Cl, CH3, SiH3, Si(OH)3) were calculated by ab-initio methods. In the most stable isomer, the ligand with the smallest trans influence is trans to the PH3 ligand. The trans influence increases in the order Cl<CH3<SiH3<Si(OH)3.
Corresponding author. E-mail: uschuber@mail.2serv.tuwien.ac.at
Received October 14, 2002; accepted October 14, 2002
Published online May 2, 2003 相似文献
10.
Gabriela Vlase T. Vlase Ramona Tudose Otilia Costişor N. Doca 《Journal of Thermal Analysis and Calorimetry》2007,88(3):637-640
Kinetics of thermal decomposition of three structurally similar complexes Co2Cu(C2O4)3 (R-diam)2, where R is ethyl, 1,2-propyl or 1,3-propyl, was studied under non-isothermal conditions and nitrogen dynamic atmosphere at heating
rates of 5, 7, 10, 12 and 15 K min−1.
For data processing the Flynn-Wall-Ozawa and a modified non-parametric kinetic methods were used. By both methods the activation
energy are in the range of 97–102 kJ mol−1. The formal kinetic is r=kα(1−α)2. Also a compensation effect between lnA and E was evidenced. The kinetic analysis lead to the conclusion of an identic decomposition mechanism by a single step process. 相似文献
11.
J. M. Santana-Casiano M. González-Dávila F. J. Millero 《Journal of solution chemistry》2008,37(6):749-762
The stability constants for the hydrolysis of Cu(II) and formation of chloride complexes in NaClO4 solution, at 25 °C, have been examined using the Pitzer equations. The calculated activity coefficients of CuOH+, Cu(OH)2, Cu2(OH)3+, Cu2(OH)22+, CuCl+ and CuCl2 have been used to determine the Pitzer parameter (β
i
(0), β
i
(1), and C
i
) for these complexes. These parameters yield values for the hydrolysis constants (log 10
β
1*, log 10
β
2*, log 10
β
2,1* and log 10
β
2,2*) and the formation of the chloride complexes (log 10
β
CuCl* and
that agree with the experimental measurements, respectively to ±0.01,±0.02,±0.03,±0.06,±0.03 and ±0.07.
The stability constants for the hydrolysis and chloride complexes of Cu(II) were found to be related to those of other divalent
metals over a wide range of ionic strength. This has allowed us to use the calculated Pitzer parameters for copper complexes
to model the stability constants and activity coefficients of hydroxide and chloride complexes of other divalent metals. The
applicability of the Pitzer Cu(II) model to the ionic strength dependence of hydrolysis of zinc and cadmium is presented.
The resulting thermodynamic hydroxide and chloride constants for zinc are
and
. For cadmium the thermodynamic hydrolysis constants are
and
. The Cu(II) model allows one to determine the stability of other divalent metal complexes over a wide range of concentration
when little experimental data are available. More reliable stepwise stability constants for divalent metals are needed to
test the linearity found for the chloro complexes. 相似文献
12.
The allylation of prochiral C-nucleophiles catalyzed by the Pd(0)—(S)-(—)-BINAP complex (BINAP is 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) was studied. The enantioselectivity of the allylation
was found to be low.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1753—1755, August, 2008. 相似文献
13.
A. R. Kudinov V. I. Meshcheryakov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1999,48(1):176-178
Compounds (η-C5R5)Fe[η-9-(Me2S)-7,8-C2B9H10] (R=H, Me) and (η-C4Me4)Co[η-9-(Me2S)-7,8-C2B9H10] were synthesized by the reactions of Na[9-(Me2S)-7,8-C2B9H10] with complexes [(η-C5H5)Fe(MeCN)3]PF6, [(η-C5Me5)Fe(MeCN)3]BF4, and [(η-C4Me4)Co(MeCN)3]PF6, respectively.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 177–179, January, 1999. 相似文献
14.
I. N. Lisichkina T. Yu. Vasil'eva D. A. Davtyan V. M. Belikov 《Russian Chemical Bulletin》1997,46(2):331-333
The formation of complexes of dehydrodipeptides bearingN-terminalN-benzoyl-O-methyl-α,β-dehydrotyrosine orN-benzoyl-α,β-dehydrovaline residues with Ca2+ and Mg2+ ions enhances the diastereoselectivity of their hydrogenation;de of 66% and 80% were achieved. This method of increasing the stereoselectivity of hydrogenation is applicable to various dehydroamino
acids at both theC- andN-termini of dehydrodipeptides.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 345–347, February, 1997. 相似文献
15.
Fadila Balegroune Pierre Braunstein Jérôme Durand Thierry Faure Daniel Grandjean Michael Knorr Maurizio Lanfranchi Chiara Massera Xavier Morise Antonio Tiripicchio 《Monatshefte für Chemie / Chemical Monthly》2001,132(8):885-896
Summary. Iodo derivatives of diphosphine-bridged heterobimetallic Fe—Pd and Fe—Pt complexeshave been prepared in which an alkoxysilyl
ligand bridges the two metals in a μ2−η2-SiO manner. In the course of their synthesis by halide exchange from (dppx = dppm (Ph2 PCH2 PPh2) or dppa (Ph2PNHPPh2); M = Pd or Pt), loss of the alkoxysilyl ligand occurred resulting in the formation of complexes in which a bridging iodide has
replaced, as a 3e−-donor, the bridging alkoxysilyl ligand. These complexes of formula (M = Pd, Pt are better prepared by reaction of with [MI2(cod)]. The crystal structures of (2a), (2b), and · CH2Cl2 (3b · CH2Cl2) have been determined by X-ray diffraction.
Received January 24, 2001. Accepted February 12, 2001 相似文献
16.
Seyed M. Hashemianzadeh Amir A. Rafati Zabiholah B. Nojini 《Monatshefte für Chemie / Chemical Monthly》2008,139(7):763-771
Quantum mechanical (QM) calculations were carried out in order to study the host-guest inclusion complexes of procaine hydrochloride
(Pro-H) and butacaine hydrochloride (But-H) with α- and β-cyclodextrins (α- and β-CDs) by PM3 and AM1 methods. The systems were studied by a 1:1 (α-CD/Pro-H, α-CD/But-H, β-CD/Pro-H, and β-CD/But-H) stoichiometric ratio. In this work we calculated the energy of complex formation in vacuo, and this investigation was carried out on the basis of the host-guest approach. The stabilization energy results for the
1:1 host-guest inclusion complexes indicate that the β-CD/Pro-H complex is more stable than the α-CD/Pro-H complex. Furthermore, stabilization energy for the 1:1 inclusion complex of α-CD with But-H is lower than that for the 1:1 inclusion complex of β-CD with But-H. The calculation results show that all complexation processes for the four complexes are exothermic. Enthalpy changes for
the α-CD/But-H and β-CD/Pro-H host-guest inclusion complexes are more negative than those for the other ones. ΔG
o values for both the β-CD/Pro-H and α-CD/But-H complexes are negative.
Correspondence: S. M. Hashemianzadeh, Department of Physical Chemistry, College of Chemistry, Iran University of Science and
Technology, Tehran, Iran. 相似文献
17.
S. N. Podyachev S. N. Sudakova A. K. Galiev A. R. Mustafina V. V. Syakaev R. R. Shagidullin I. Bauer A. I. Konovalov 《Russian Chemical Bulletin》2006,55(11):2000-2007
New chelating ligands consisting of three β-diketone fragments, viz., 1,3,5-tris[(acetylaceton-3-yl)methyl]benzene, 1,3,5-tris[(benzoylaceton-3-yl)methyl]benzene, and 1,3,5-tris[(dibenzoylmethan-1-yl)methyl]benzene,
linked to each other through the mesitylene spacer were synthesized by the reaction of 1,3,5-tris(bromomethyl)benzene with
the corresponding β-diketone sodium salt. The acidity of these compounds and their complexation properties were studied by
pH-potentiometry in aqueous-ethanol solutions. Tris(β-diketones) form mononuclear complexes with lanthanide ions, whose stability
increases in the series La3+ < Gd3+ < Lu3+. 1,3,5-Tris[(acetylaceton-3-yl)methyl]benzene forms both mononuclear and polynuclear complexes with the Ni2+ and Cu2+ ions. The stability constants and selectivity of complex formation increase substantially with an increase in the degree
of deprotonation of the ligands, thus indicating that all deprotonated chelate groups are involved in coordination with the
metal ion. The replacement of the methyl groups by the phenyl substituents in the β-diketone fragments of the molecules affects
substantially the composition and stability of the complexes formed.
Dedicated to Academician O. M. Nefedov on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1926–1933, November, 2006. 相似文献
18.
Seyed Majid Hashemianzadeh Shirin Faraji Amir Hossein Amin Sepideh Ketabi 《Monatshefte für Chemie / Chemical Monthly》2008,139(2):89-100
Summary. Interactions of the DNA bases adenine (A), guanine (G), cytosine (C), and thymine (T) with various metal ions (M) of groups IA and IIA of the periodic table of the elements were studied at the HF, MP2, and DFT levels of theory. The structures and thermodynamic stabilities of these species were studied at the gas phase. The calculations
uphold that there exist two active sites in G and one in A, C, and T. The calculations also show that the O2 atom in T is a more active site for metal ion bindings than that in C. The stability energies for G … M complexes are larger than those for A … M complexes and the stability energies for T … M complexes are larger than those for C … M complexes. As z/r ratio for the metal ion increases, the interaction energy for the complex increases systematically. Thermodynamic quantities
such as ΔH, ΔG, ΔS, and ln K were determined for each complexation reaction, [Base+M
n+ →(Base … M)
n+]. A, G, and C complexation reactions except for C … Rb+ are exothermic. The situation is quite different for T complexation reactions and all except for T … Be2+ and T … Mg2+ are endothermic. 相似文献
19.
The inclusion complexes of a series of bis-quarternary ammonium surfactants, (C
n
N)2Cl2 (where n = 12, 14, 16) and sodium bis(2-ethylhexyl) sulfosuccinae (AOT), with α-cyclodextrin (α-CD), β-cyclodextrin (β-CD) and γ-cyclodextrin (γ-CD) in aqueous solutions were investigated by using isothermal titration calorimetry (ITC) at 298.15 K. The stability constants,
stoichiometry, and formation enthalpies, entropies and Gibbs energies for the complexes in aqueous solutions have been derived
from the calorimetric data. The values of the binding constant, K
∘
i
, are very large, which indicates that these complexes are quite stable in their aqueous solutions. The enthalpy changes (ΔH
∘) for all of the inclusion processes are negative, showing that the complex process is enthalpy driven. The entropy effect
(TΔS
∘) is negative, so the inclusion process is entropically unfavorable. The large negative Gibbs energy changes indicate that
formation of host-guest inclusion complexes is generally a spontaneous process. The thermodynamic parameters are discussed
in the light of the different structures of the host and guest molecules. 相似文献
20.
M. A. M. Al-Gurashi A. A. B. El-Ahmadi S. M. A. Katib K. M. Abd El-Salaam 《Journal of Thermal Analysis and Calorimetry》1994,41(4):859-870
Thermal decomposition of cobalt and nickel nicotinate was studied by TG, DTG and DSC. The mechanism of decomposition has been
established from TG and DSC data. The kinetic parameters namelyE, A together with ΔH were calculated from DSC curves using mechanistic and non-mechanistic integral equations.
Zusammenfassung Mittels TG, DTG und DSC wurde die thermische Zersetzung von Cobaltund Nickelnikotinat untersucht. Der Zersetzungsmechanismus wurde anhand der TG-und DSC-Daten entwickelt. Die kinetischen ParameterE, A wurden zusammen mit ΔH anhand der DSC-Kurven mit Hilfe von mechanistischen und nichtmechanistischen Integrationsgleichungen berechnet.相似文献