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1.
Wang Zhong-Ming Lin Hua-Kuan Zhou Zhi-Fen Zhu Shou-Rong Chen Yun-Ti Murmann R. Kent 《Transition Metal Chemistry》2000,25(5):562-567
The kinetics of the reaction of CH2O with a quasi-aromatic metal complex (1,1,2,8,9,9-hexamethyl-4,6-dioxa-5-hydro-3,7,10,14-tetraazacyclotetradecane-2,7,10,12-tetraene)copper(II), [Cu(PnAO)-6H]0 (AH), have been studied spectrophotometrically under neutral conditions in 1/3(v/v) MeOH–H2O. The Cu, 2N, 3C quasi-aromatic heterocyclic ring in AH is highly reactive towards CH2O at the central-aromatic-carbon atom, C(12) and the following reaction mechanism is proposed.
The compounds AH, A—CH2OH and A—CH2—A were isolated and identified by i.r spectroscopy and by elemental analysis. The kinetic data supported the proposed reaction sequence. All reactions were second order overall. The rate constants and corresponding activation parameters for every step were obtained and are discussed. 相似文献
2.
The kinetics fo dissociation of thebis complexes [Cu(LH)2]2+ formed by CuII with biguanide andN
1-substituted methyl, phenyl, dimethyl and diethyl biguanides into the mono biguanide complexes in aqueous NaOAc-HOAc buffer media have been studied by stopped-flow spectrophotometry. The results, under pseudo-first-order conditions, indicate kobs=ko+kH[H+]. For the different complexes ko values are comparable, but kH values differ appreciably; log kH
versus log K
d
H
is linear withca. unit slope K
d
H
being the equilibrium constant for the process:
相似文献
3.
Reena Singh Atanu Banerjee Yee Gordon Kajal Krishna Rajak 《Transition Metal Chemistry》2009,34(6):689-694
Abstract The title complexes and have been synthesized in excellent yields by reacting Co(OAc)2·4H2O with H2L1 and H2L2, respectively, in acetonitrile solution. Here, [L1]2− and [L2]2− are the deprotonated forms of N,N-bis(2-hydroxybenzyl)-N′,N′-dimethylethylenediamine and N,N-bis(2-hydroxybenzyl)-2-picolylamine, respectively. The crystal structures of and were determined by x-ray crystallography. In , each cobalt atom has distorted trigonal bipyramid geometry, while in , each cobalt atom has distorted octahedral geometry. Variable temperature magnetic moment measurements show weak antiferromagnetic
interaction in . The magnetic characterization for is in agreement with the presence of Co(II) and Co(III) centers.
Graphical Abstract The title complexes and have been synthesized in excellent yields by reacting Co(OAc)2·4H2O with dianionic N2O2 coordinating ligands. In complex 1, each cobalt atom has distorted trigonal bipyramid geometry, while in complex 2, each
cobalt atom has distorted octahedral geometry. Variable temperature magnetic moment measurements show weak antiferromagnetic
interaction in complex 1. The magnetic characterization for complex 2 is in agreement with the presence of Co(II) and Co(III)
centers.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
4.
Sarada Gopinathan Shilpa S. Deshpande Changaramponnath Gopinathan 《Transition Metal Chemistry》1993,18(6):585-587
Summary Hexacoordinated ruthenium(II) alkenyl complexes of the type Ru(CO)(CR=CHPh)(
)(PPh3)2 have been prepared from coordinately unsaturated -vinyl complexes [Ru(CO)Cl(CR=CHPh)(PPh3)2] (R = H or Ph) and the sodio-derivative of the
containing heterocyclic ligands [
= 3,4-substituted 1,2,4-triazole-5-thione and 5-alkylthio-1,3,4-thiadiazole-2-thione] in a CH2Cl2/MeOH mixture at ambient temperature. The complexes were characterized by their elemental analysis, i.r., 1H and 31P n.m.r. spectra. An octahedral structure with transphosphorus ligands has been assigned on the basis of the spectral data. 相似文献
5.
Behzad Soltani Moayad Hossaini Sadr James T. Engle Christopher J. Ziegler Sang Woo Joo Younes Hanifehpour 《Transition Metal Chemistry》2012,37(8):687-694
Three new binuclear copper complexes of formulae $ \left[ {{\text{Cu}}_{2}^{\text{II}} {\text{Pz}}_{2}^{\text{Me3}} {\text{Br}}_{ 2} \left( {{\text{PPh}}_{ 3} } \right)_{ 2} } \right] $ (1), $ \left[ {{\text{Cu}}_{ 2}^{\text{II}} {\text{Pz}}_{2}^{\text{Ph2Me}} {\text{Cl}}_{ 2} \left( {{\text{PPh}}_{ 3} } \right)_{ 2} } \right] $ (2) and $ \left[ {{\text{Cu}}_{2}^{\text{II}} \left( {{\text{Pz}}^{\text{PhMe}} } \right)_{ 4} {\text{Cl}}_{ 4} } \right] $ (3) (PzMe3?=?3,4,5-trimethylpyrazole, PzPh2Me?=?4-methyl-3,5-diphenylpyrazole and PzPhMe?=?3-methyl-5-phenylpyrazole) have been synthesized and characterized by chemical analysis, FTIR and 31P NMR spectroscopy and single-crystal X-ray diffraction. Complex 1 is a doubly bromo-bridged dimer, while complexes 2 and 3 are chloro-bridged dimers. The Cu(II) centers are in a distorted tetrahedral geometry for 1 and 2 and a distorted square pyramidal N2Cl3 environment for 3. 相似文献
6.
Summary Aquocomplexes of copper(II) and nickel(II) involving (H2NCH2)2, H2NCH2CH2NHCH2CH2NH2 and H2NCH2CH2NHCH2CH2NHCH2CH2NH2 as ligands were prepared and characterised. Using a pH-stat method, the kinetics of the base hydrolysis of amino acid esters such as H2NCH2CO2CH3·HCl (GE), (HO)C6H4CH2-(NH2)CO2CH3·HCl (TE), CH3S(CH2)2CH(NH2)CO2CH3· HCl (ME), HSCH2CH(NH2)CO2C2H5·HCl (CE),
(HE) and [—SCH2CH(NH2)CO2CH3]2·2HCl (CysE) was studied. These complexes substantially enhance the rate of hydrolysis, the values of the second-order rate constants being some 10–30 times greater than those obtained in the presence of simple metal ions. 相似文献
7.
Luminescence Behavior of Polynuclear Alkynylcopper(I) Phosphines 总被引:1,自引:0,他引:1
A series of soluble trinuclear and tetranuclear copper(I) complexes containing 3-l acetylides
, and
have been synthesized and shown to exhibit rich photoluminescent behavior at room temperature. The electrochemistry of the trinuclear Cu(I) acetylide complexes and the excited-state redox properties of
have been investigated. The X-ray crystal structures of
and
have been determined. 相似文献
8.
By analyzing the topological structures of the three types of icosahedral fullerenes: (1)
, (2)
and (3)
k,\;h,k = 1,2,...} \right)$$
" align="middle" border="0">
, we have obtained theoretically the 13C NMR spectra with natural abundance for 13C of all the icosahedral (Ih and I) fullerenes. 相似文献
9.
Polosukhin A. I. Bondarev O. G. Lyubimov S. E. Shiryaev A. A. Petrovskii P. V. Lysenko K. A. Gavrilov K. N. 《Russian Journal of Coordination Chemistry》2001,27(8):591-597
Phosphorylation of (S)-prolinol with P(NEt2)3was used to synthesize aminophosphite (2R,5S)-
, which was reacted with the corresponding amino alcohols to afford (2S,5R)-
(Va) and (2S,5R)-
(Vb). Reaction of Vawith [Rh(CO)2Cl]2(P/Rh = 1) yields the mononuclear chelate [Rh(CO)(P^N)Cl] (VIIa), while the analogous reaction with Vbresults in a mixture of products with cis- and trans-orientation of the coordinated phosphorus and nitrogen atoms. Spectral characteristics of the products of coordination of ligands Vaand Vbwere compared with those for the binuclear reference complex [Rh(CO)(L)Cl]2(VIII), where L is P-monodentate ligand (2S,5R)-
(VI). The ligands and complexes were studied by IR, NMR, 31P and 13C spectroscopy, mass spectrometry, and elemental analysis methods. X-ray diffraction analysis of crystals VIIIwas performed. 相似文献
10.
The oxidation of H2NOH is first-order both in [NH3OH+] and [AuCl4
–]. The rate is increased by the increase in [Cl–] and decreased with increase in [H+]. The stoichiometry ratio, [NH3OH+]/[AuCl4
–], is 1. The mechanism consists of the following reactions.
11.
Sheng-Xiong Xiao Jian-Hong Jiang Xu Li Chuan-Hua Li Hui Zhang Fei-Hong Yao You Li Qiang-Guo Li 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1139-1144
The product, [Pr(C7H5O3)2(C9H6NO)], which was formed by praseodymium nitrate hexahydrate, salicylic acid (C7H6O3), and 8-hydroxyquinoline (C9H7NO), was synthesized and characterized by elemental analysis, UV spectra, IR spectra, molar conductance, and thermogravimetric analysis. In an optimalizing calorimetric solvent, the dissolution enthalpies of [Pr(NO3)3·6H2O(s)], [2 C7H6O3(s) + C9H7NO(s)], [Pr(C7H5O3)2(C9H6NO)(s)], and [solution D (aq)] were measured to be, by means of a solution-reaction isoperibol microcalorimeter, $ \begin{gathered}\Updelta_{\text{s}} H_{\text{m}}^{\theta}\left[ {{ \Pr }\left( {{\text{NO}}_{ 3} } \right)_{ 3} \cdot 6{\text{H}}_{ 2} {\text{O}}\left( {\text{s}} \right), 2 9 8. 1 5{\text{ K}}} \right] \, = - ( 20. 6 6 { } \pm \, 0. 29)\,{\text{kJ}}\,{\text{mol}}^{ - 1} , \\\Updelta_{\text{s}} H_{\text{m}}^{\theta } \left[ { 2 {\text{C}}_{7} {\text{H}}_{ 6} {\text{O}}_{ 3} \left( {\text{s}} \right) +{\text{ C}}_{ 9} {\text{H}}_{ 7} {\text{NO}}\left( {\text{s}}\right),{ 298}. 1 5 {\text{ K}}} \right] \, = \, ( 4 2. 2 7 { }\pm \, 0. 3 1)\,{\text{kJ}}\,{\text{mol}}^{ - 1} , \\\Updelta_{\text{s}} H_{\text{m}}^{\theta } \left[ {{\text{solutionD }}\left( {\text{aq}} \right), 2 9 8. 1 5 {\text{ K}}} \right] \,= - \left( { 8 9. 1 5 { } \pm \, 0. 4 3}\right)\,{\text{kJ}}\,{\text{mol}}^{ - 1} , \\\end{gathered} $ Δ s H m θ [ Pr ( NO 3 ) 3 · 6 H 2 O ( s ) , 2 9 8.1 5 K ] = ? ( 20.6 6 ± 0.2 9 ) kJ mol ? 1 , Δ s H m θ [ 2 C 7 H 6 O 3 ( s ) + C 9 H 7 NO ( s ) , 298.1 5 K ] = ( 4 2.2 7 ± 0.3 1 ) kJ mol ? 1 , Δ s H m θ [ solution D ( aq ) , 2 9 8.1 5 K ] = ? ( 8 9.1 5 ± 0.4 3 ) kJ mol ? 1 , and $ \Updelta_{\text{s}} H_{\text{m}}^{\theta } \left\{ {\left[ {{\Pr }\left( {{\text{C}}_{ 7} {\text{H}}_{ 5} {\text{O}}_{ 3} }\right)_{ 2} \left( {{\text{C}}_{ 9} {\text{H}}_{ 6} {\text{NO}}}\right)} \right]\left( {\text{s}} \right),{ 298}. 1 5 {\text{ K}}}\right\} \, = - \left( { 4 1.0 4 { } \pm \, 0. 3 3}\right)\,{\text{kJ}}\,{\text{mol}}^{ - 1} $ Δ s H m θ { [ Pr ( C 7 H 5 O 3 ) 2 ( C 9 H 6 NO ) ] ( s ) , 298.1 5 K } = ? ( 4 1.0 4 ± 0.3 3 ) kJ mol ? 1 , respectively. Through an improved thermochemical cycle, the enthalpy change of the designed coordination reaction was calculated to be $\Updelta_{\text{r}} H_{\text{m}}^{\theta} = \, ( 2 1 3. 1 8\pm0. 6 9)\,{\text{kJ}}\,{\text{mol}}^{ - 1} $ Δ r H m θ = ( 2 1 3.1 8 ± 0.6 9 ) kJ mol ? 1 , the standard molar enthalpy of the formation was determined as $ \Updelta_{\text{f}} H_{\text{m}}^{\theta} \left\{ {\left[ {{\Pr }\left( {{\text{C}}_{ 7} {\text{H}}_{ 5} {\text{O}}_{ 3} }\right)_{ 2} \left( {{\text{C}}_{ 9} {\text{H}}_{ 6} {\text{NO}}}\right)} \right]\left( {\text{s}} \right), 2 9 8. 1 5 {\text{K}}}\right\} \, = \, - \, ( 1 8 7 5. 4\pm 3.1)\,{\text{kJ}}\,{\text{mol}}^{ - 1} $ Δ f H m θ { [ Pr ( C 7 H 5 O 3 ) 2 ( C 9 H 6 NO ) ] ( s ) , 2 9 8.1 5 K } = ? ( 1 8 7 5.4 ± 3.1 ) kJ mol ? 1 . 相似文献
12.
The reaction of ethyleneimine with sulfenyl chlorides RSCl at –10 C in the presence of a hydrogen chloride acceptor (triethylamine) leads to the formation of N-organylthioaziridines
. Compounds with R=n-C5H11, C6H5, o-O2NC6H4 and C6H6CH2 have been obtained by this method.
and
. have been synthesized analogously.The properties and IR spectra of these compounds have been studied. The action of methyl iodide on N-phenylthioaziridine leads to disproportionation of the molecule with the formation of diphenyl disulfide, -iodoethyltrimethylammonium iodide, and free iodine.For communication VI, see [I]. 相似文献
13.
Rajendiran Thekkel M. Mahalakshmy Rajaram Kannappan Ramu Rajeswari Janarthanam Venkatesan Rangarajan Rao Pillutla 《Transition Metal Chemistry》2003,28(3):280-287
Binuclear CuII complexes having new flexible heptadentate ligands 2,6-bis{[bis(3,3-N,N-dimethylaminopropyl)amino]methyl}-4-bromophenol [HL1], 2,6-bis(3,3-N,N-dimethylaminopropyl)amino]methyl}-4-methylphenol [HL2], and 2,6-bis{[bis(3,3-N,N-dimethylaminopropyl)amino]methyl}-4-methoxyphenol [HL3], capable of assembling two copper ions in close proximity have been synthesized. Comparisons of the charge-transfer (CT) features, observed in electronic spectra of these complexes, are correlated with the electronic effect on the aromatic ring of the ligand systems. Cyclic voltammetry has revealed the existence of two reduction couples,
14.
Complexes of ferratrane-3,7,10-trione
(I) of the composition I · H2O, I · H2O2, I · OS(CH3)2, and I · 2OS(CH3)2 were synthesized. The IR spectra and derivatograms of these compounds were studied.See [1] for communication XXXI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 164–170, February, 1973. 相似文献
15.
Summary The oxidation of H2O2 by [W(CN)8]3– has been studied in aqueous media between pH 7.87 and 12.10 using both conventional and stopped-flow spectrophotometry. The reaction proceeds without generation of free radicals. The experimental overall rate law,
, strongly suggests two types of mechanisms. The first pathway, characterized by the pH-dependent rate constant k
s, given by
, involves the formation of [W(CN)8· H2O2]3–, [W(CN)8· H2O2·W(CN)8]6– and [W(CN)8· HO]3– intermediates in rapid pre-equilibria steps, and is followed by a one-electron transfer step involving [W(CN)8·HO]3– (k
a) and its conjugate base [W(CN)8·O]4– (k
b). At 25 °C, I = 0.20 m (NaCl), the rate constant
with H
a
=40±6kJmol–1 and S
a
=–151±22JK–1mol–1; the rate constant
with H
b
=36±1kJmol–1 and S
b
=–136±2JK–1mol–1 at 25 °C, I = 0.20 m (NaCl); the acid dissociation constant of [W(CN)8·HO]3–, K
5
=(5.9±1.7)×10–10
m, with
and
is the first acid dissociation constant of H2O2. The second pathway, with rate constant, k
f, involves the formation of [W(CN)8· HO2]4– and is followed by a formal two-electron redox process with [W(CN)8]3–. The pH-dependent rate constant, k
f, is given by
. The rate constant k
7
=23±6m
–1
s
–1 with
and
at 25°C, I = 0.20 m (NaCl). 相似文献
16.
Mihaela Badea Petru Budrugeac Andrei Cucos Eugen Segal 《Journal of Thermal Analysis and Calorimetry》2014,115(2):1999-2005
The thermal stability and the decomposition steps of bis(pyridine)manganese(II) chloride (Mn(py)2Cl2) were determined by thermogravimetry and derivative thermogravimetry. The initial compound and the solid compounds resulted from each step of decomposition were characterized by FT-IR spectroscopy and RX diffraction. It was pointed out that at the progressive heating of Mn(py)2Cl2, the following decomposition reactions occur:
17.
The enthalpies and entropies of evaporation of Al(CH3)3–Sn(CH3)4and Ga(CH3)3–Sn(CH3)4solutions were determined. It was established that solvates are formed in these systems and that the dissociation energies of specific interactions in them change in the following order:
(10.3) >
>
>
(4.08 kJ mol–1),
(6.52) >
(5.14) >
>
(4.08 kJ mol–1). 相似文献
18.
Y. P. Liu Y. Y. Di W. Y. Dan D. H. He 《Journal of Thermal Analysis and Calorimetry》2012,109(1):287-293
Bis(1-octylammonium) tetrachlorocuprate (1-C8H17NH3)2CuCl4(s) was synthesized by the method of liquid phase reaction. The crystal structure of the compound has been determined by X-ray crystallography. The lattice potential energy was obtained from the crystallographic data. Molar enthalpies of dissolution of (1-C8H17NH3)2CuCl4(s) at various molalities were measured at 298.15?K in the double-distilled water by means of an isoperibol solution-reaction calorimeter, respectively. In terms of Pitzer??s electrolyte solution theory, the molar enthalpy of dissolution of (1-C8H17NH3)2CuCl4(s) at infinite dilution was determined to be $ \Updelta_{\rm s} H_{\text{m}}^{\infty } = \, - 5. 9 7 2\,{\text{kJ}}\,{\text{mol}}^{ - 1} , $ and the sums of Pitzer??s parameters $ (4\beta_{{{\text{C}}_{ 8} {\text{H}}_{ 1 7} {\text{NH}}_{ 3} , {\text{Cl}}}}^{ ( 0 )L} + 2\beta_{\text{Cu,Cl}}^{ ( 0 )L} + \theta_{{{\text{C}}_{ 8} {\text{H}}_{ 1 7} {\text{NH}}_{ 3} , {\text{Cu}}}}^{L} ) $ and $ (2\beta_{{{\text{C}}_{ 8} {\text{H}}_{ 1 7} {\text{NH}}_{ 3} , {\text{Cl}}}}^{ ( 1 )L} + \beta_{\text{Cu,Cl}}^{ ( 1 )L} ) $ were obtained. 相似文献
19.
Isothermal compressibilities T and isobaric thermal expansion coefficients p have been determined for mixtures of ethylbenzene+n-nonane, +n-decane, and +n-dodecane at 25 and 45°C in the whole range of composition. The excess functions
and
have been obtained at each measured mole fraction. The first one
is zero for ethylbenzene +n-nonane, positive for ethylbenzene +n-decane, and +n-dodecane and increases with chain length n of the n-alkane. The
function is positive for the three studied systems and nearly constant with n. Both mixing functions increase slightly with temperature. From this measurement and supplementary literature data of molar heat capacities at constant pressure C
P
, the isentropic compressibilities S, the molar heat capacities at constant volume C
V
and the corresponding mixing functions have been calculated at 25°C. Furthermore, the pressure dependence of excess enthalpy H
B
,
at zero pressure and at 25°C has been obtained from our experimental results of
and experimental literature values for excess volume V
E
. 相似文献
20.
The solubility of rhodochrosite (MnCO3) at 25°C under constant carbon dioxide partial pressure p(CO2) was determined in NaCl solutions as a function of ionic strength I. The dissolution of MnCO3(s) for the reaction
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