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1.
E. Makrlík P. Vaňura P. Selucky Z. Spíchal 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(1):13-18
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of 1,2-(diphenylphosphino)ethane dioxide (DPPEtDO, L) has been investigated. The equilibrium data have been
explained assuming that the species HL+, HL2
+, ML2
3+ and ML4
3+ (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. It was found that the stability constants of the corresponding complexes EuL
n
3+ and AmL
n
3+, where n = 2, 4 and L is DPPEtDO, in water-saturated nitrobenzene are comparable. 相似文献
2.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):571-575
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of tetraisopropyl methylene diphosphonate [T(iPr)MDP, L] has been investigated. The equilibrium data have
been explained assuming that the complexes HL+, HL2
+, ML2
3+, ML3
3+ and ML4
3+ (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. It was found that the stability constants of the corresponding complexes EuL
n
3+ and AmL
n
3+, where n = 2, 3, 4 and L is T(iPr)MDP, in water-saturated nitrobenzene are comparable. 相似文献
3.
M. M. Degtyarik A. S. Lyakhov O. A. Ivashkevich Yu. V. Grigoriev 《Russian Journal of Coordination Chemistry》2012,38(2):77-85
The reactions of Co(II), Ni(II), and Cu(II) chlorides and bromides and their metallic powders with tetrazol-1-yl-tris(hydroxymethyl)methane
(L) afforded new complexes ML2Hal2 · mH2O(M = Co(II) or Ni(II), Hal = Cl−; M = Cu(II), Hal = Cl− or Br−, m = 0; and M = Co(II) or Ni(II), Hal = Br−, m = 2), MLnCl2 (M = Co(II) or Ni(II), n = 2 or 4; M = Cu(II), n = 2), and MLnBr2 · mH2O (M = Ni(II), n = 2, m = 2; M = Cu(II), n = 2, m = 0). The compositions and structures of the synthesized complexes were determined by elemental analysis, IR spectroscopy
(50–4000 cm−1), and X-ray diffraction analysis. The introduction of a bulky substituent into position 1 of the tetrazole cycle was shown
to exert almost no effect on the coordination mode but affected the composition and structure of the complexes. 相似文献
4.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(1):217-222
Extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of tetraisopropyl methylene diphosphonate [T(iPr)MDP, L] has been investigated. The equilibrium data have
been explained assuming that the species HL+,
\textHL2 + {\text{HL}}_{2}^{ + } ,
\textML22 + {\text{ML}}_{2}^{2 + } and
\textML32 + {\text{ML}}_{3}^{2 + } (M2+ = Ca2+, Sr2+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complexes in nitrobenzene
saturated with water have been determined. In the considered nitrobenzene medium, it was found that the stability constants
of the
\textCaLn2 + {\text{CaL}}_{n}^{2 + } complexes, where n = 2, 3 and L is T(iPr)MDP, are somewhat higher than those of the corresponding complex species
\textSrLn2 + {\text{SrL}}_{n}^{2 + } . 相似文献
5.
Derivative of 8-hydroxyquinoline i.e. Clioquinol is well known for its antibiotic properties, drug design and coordinating
ability towards metal ion such as Copper(II). The structure of mixed ligand complexes has been investigated using spectral,
elemental and thermal analysis. In vitro anti microbial activity against four bacterial species were performed i.e. Escherichia coli, Pseudomonas aeruginosa, Serratia marcescens, Bacillus substilis and found that synthesized complexes (15–37 mm) were found to be significant potent compared to standard drugs (clioquinol
i.e. 10–26 mm), parental ligands and metal salts employed for complexation. The kinetic parameters such as order of reaction
(n = 0.96–1.49), and the energy of activation (E
a = 3.065–142.9 kJ mol−1), have been calculated using Freeman–Carroll method. The range found for the pre-exponential factor (A), the activation entropy (S* = −91.03 to−102.6 JK−1 mol−1), the activation enthalpy (H* = 0.380–135.15 kJ mol−1), and the free energy (G* = 33.52–222.4 kJ mol−1) of activation reveals that the complexes are more stable. Order of stability of complexes were found to be [Cu(A4)(CQ)OH] · 4H2O > [Cu(A3)(CQ)OH] · 5H2O > [Cu(A1)(CQ)OH] · H2O > [Cu(A2)(CQ)OH] · 3H2O 相似文献
6.
Two two-dimensional coordination complexes, {[Cu4(BTM)6(OPA)4] · 4DMF · 3H2O}
n
(1) and {[Cu(BDTM)(OH)](ClO4) · 2H2O}
n
(2) (BTM = bis(1,2,4-triazol-1-yl)methane, BDTM = bis(3,5-dimethyl-1,2,4-triazol-1-yl)methane, OPA2− = ortho-phthalic dianion, DMF = N,N-dimethylformamide), were synthesized and structurally characterized. Each Cu(II) ion locates in a distorted square pyramidal
geometry in 1, in which OPA2− ligands bridge Cu2+ ions along a axis to form a magnetic transmission chain and BTM ligands act as flexible spacers to construct the two-dimensional layer
structure. In 2, each Cu2+ ion adopts tetra-coordination geometry to two hydroxyl groups and two triazolyl nitrogen atoms from two different BDTM ligands.
Two hydroxyl groups bridge two Cu2+ ions to form a rhombic diamond, and four BDTM ligands connect four diamonds to form a 36-membered macrocyclic structure with
large channels along a axis. Magnetic properties revealed that both OPA2− and OH− mediate anti-ferromagnetic interactions between Cu2+ ions with J = − 0.06(3) and −301.9(2) cm−1 for 1 and 2, respectively.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
Shanmugam Sreedaran Kuppannan Shanmuga Bharathi Aziz Kalilur Rahiman Raju Prabu Raman Jagadesh Nanjian Raaman Vengidusamy Narayanan 《Transition Metal Chemistry》2009,34(1):33-41
A series of trinuclear Cu(II) complexes have been prepared by Schiff base condensation of 1,8-[bis(3-formyl-2-hydroxy-5-methyl)benzyl]-l,4,8,11-tetraazacyclotetradecane
and 1,8-[bis(3-formyl-2-hydroxy-5-bromo)benzyl]-l,4,8,11-tetraazacyclotetradecane with aromatic and aliphatic diamines, Cu(II)
perchlorate and triethylamine. The complexes were characterized by elemental and spectroscopic analysis. Electrochemical studies
of the complexes in DMF solution show three irreversible one-electron reduction processes around Epc
1 = −0.73 to −0.98 V, Epc
2 = −0.91 to −1.20 V and Epc
3 = −1.21 to −1.33 V. ESR spectra and magnetic moments of the trinuclear Cu(II) complexes show the presence of antiferromagnetic
coupling. The rate constants for hydrolysis of 4-nitrophenylphosphate by the Cu(II) complexes are in the range of 3.33 × 10−2 to 7.58 × 10−2 min−1. The rate constants for the catecholase activity of the complexes fall in the range of 2.67 × 10−2 to 7.56 × 10−2 min−1. All the complexes were screened for antifungal and antibacterial activity. 相似文献
8.
E. Makrlík P. Vaňura P. Selucky V. A. Babain I. V. Smirnov 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):839-844
Extraction of microamounts of europium and americium by a phenyltrifluoromethyl sulfone (FS 13) solution of hydrogen dicarbollylcobaltate
(H+B−) in the presence of N,N,N′,N′-tetraethyl-2,6-dipicolinamide (TEtDPA, L) has been investigated. The equilibrium data have been explained assuming that the
species HL+,
\textHL 2 + , {\text{HL}}_{ 2}^{ + } ,
\textML23 + {\text{ML}_{2}^{3 +}} and
\textML 3 3+ {\text{ML}_{ 3}^{ 3+}} (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in
FS 13 saturated with water have been determined. It was found that the stability constants of the corresponding complexes
\textEuLn 3+ {\text{EuL}}_{n}^{ 3+ } and
\textAmLn 3+ {\text{AmL}}_{n}^{ 3+ }, where n = 2, 3 and L is TEtDPA, in the mentioned FS 13 medium are comparable. 相似文献
9.
Lucica Viorica Ababei Angela Kriza Adina Magdalena Musuc Cristian Andronescu Elena Adina Rogozea 《Journal of Thermal Analysis and Calorimetry》2010,101(3):987-996
New complexes of 2-benzoyl-pyridil-isonicotinoylhydrazone (L) with Cu(II), Co(II), Ni(II) and Mn(II), having formula of type
[ML2] SO4·xH2O (M = Cu2+, Co2+, Ni2+, x = 2 and M = Mn2+, x = 3), have been synthesised and characterised. All complexes were characterised on the basis of elemental analyses, IR spectroscopy,
UV–VIS–NIR, EPR, as well as thermal analysis and determination of molar conductivity and magnetic moments. The thermal behaviour
of complexes was studied using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry
(DSC). The structure of L hydrazone was established by X-ray study on single crystal. The ligand works as tridentate NNO,
being coordinated through the azomethine nitrogen, the pyridine nitrogen and carbonylic oxygen. Heats of decomposition, ΔH, associated with the exothermal effects were also determined. 相似文献
10.
Two-dimensional complexes of [Cd(cpoa)(o-pbim)]
n
(1) and {[Cd3(cpoa)3(o-pbim)2] · 2H2O}
n
(2) (cpoa2− = 4-carboxyphenoxy acetate, o-pbim = 2-(2-pyridyl)benzimidazole) are synthesized under hydrothermal condition. Single crystal
X-ray diffraction analysis shows that complex 1 contains a mono-nuclear unit, whereas complex 2 contains a trinuclear unit. The structural difference of 1 and 2 can be attributed to the various coordination modes of asymmetrically semi-flexible cpoa2− ligand. The luminescent properties of these two compounds are also investigated. 相似文献
11.
Rodica Olar Mihaela Badea Dana Marinescu Veronica Lazar Carmen Chifiriuc 《Journal of Thermal Analysis and Calorimetry》2009,97(2):721-727
Schiff bases obtained by the condensation of 2-amino-5-mercapto-1,3,4-thiadiazole with 2,4-pentandione or 1-phenyl-1,3-butandione
were synthesized and characterized in order to obtain polydentate ligands HL1 and HL2, respectively. The complexes with these ligands of the type M(L)Cl·nH2O [(1) M:Ni, L:L1, n = 0.5; (3) M:Ni, L:L2, n = 0.5]; [(2) M:Cu, L:L1, n = 1; (4) M:Cu, L:L2, n = 0] were also synthesized and characterized. The modifications evidenced in IR spectra of complexes were correlated with
the presence of monodeprotonate Schiff bases. The electronic spectra display the characteristic pattern of square-planar stereochemistry.
The in vitro qualitative and quantitative antimicrobial activity assays showed that the new complexes exhibited variable antimicrobial
activity. The thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany
them. Schiff bases and complexes have a similar thermal behaviour. Processes as water elimination, melting, chloride anion
removal as well as oxidative degradation of the organic ligands were observed. 相似文献
12.
New asymmetric bidentate Schiff-base ligand (5-bromo-2-hydroxybenzyl-2-furylmethyl)imine, (HL), and its nickel(II) and copper(II)
complexes with the general composition ML2 [M = Ni (1) and Cu (2)], were prepared. The ligand and the metal complexes were characterized by elemental analysis, FT-IR, and UV–Vis spectroscopy.
In addition, 1H-NMR and X-ray powder diffraction (XRD) were employed for characterization of ligand and metal complexes, respectively. Thermogravimetric
analysis (TGA) of the ligand and metal complexes revealed the thermal stability and decomposition pattern of the species. 相似文献
13.
E. Makrlík P. Vaňura P. Selucký 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(1):137-142
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of diphenyl-N-butylcarbamoylmethyl phosphine oxide (DPBCMPO, L) has been investigated. The equilibrium data
have been explained assuming that the complexes HL+, HL2+, ML23+, ML33+ and ML43+ (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated
with water have been determined. It has been found that the stability constants of the corresponding complexes EuL
n
3+ and AmL
n
3+, where n = 2, 3, 4 and L is DPBCMPO, in water saturated nitrobenzene are comparable. 相似文献
14.
Two series of copper (I) halide complexes formulated as [(L)CuX(μ2-L)2CuX(L)] and [(L)2Cu(μ2-L)2Cu(L)2]2+ 2Χ−, respectively (X = Cl, Br and L = 4,6-dimethylpyrimidine-2-thione (dmpymtH)) were prepared. From the thermogravimetric curves
it was found that among the four studied materials, [Cu2(dmpymtH)6]2+2Cl− presents a lower thermal stability. For the determination of the activation energy (E) two different methods have been used comparatively, since every method has its own error. These methods were the isoconversional
methods of Ozawa, Flynn and Wall (OFW), and Friedman. The dependence of the E on the value of the mass conversion α, as calculated with OFW and Friedman’s methods, can be separated in three distinct regions. The decomposition mechanism is
very complex and can be described using at least three different mechanisms with different activation energies. The best fitting
of experimental data with theoretical models gave nth-order for all the three mechanisms (Fn–Fn–Fn). 相似文献
15.
Wen-Kui Dong Gang Wang Shang-Sheng Gong Jun-Feng Tong Yin-Xia Sun Xiong-Hou Gao 《Transition Metal Chemistry》2012,37(3):271-277
Two new Cu(II) complexes, [Cu(L1)2] (1) and [Cu(L2)2] (2) (HL1 = (E)-3-bromo-5-chloro-2-hydroxy benzaldehyde O-methyl oxime; HL2 = (E)-3-bromo-5-chloro-2-hydroxy benzaldehyde O-ethyl oxime), have been synthesized and characterized by physicochemical and spectroscopic methods. X-ray crystallographic
analyses show that complexes 1 and 2 have similar structures, consisting of one Cu(II) atom and two L− units. In both complexes, the Cu(II) atom, lying on an inversion center, is four-coordinated in a trans-CuN2O2 square-planar geometry by two phenolate O and two oxime N atoms from two symmetry-related N,O-bidentate oxime ligands. Moreover,
both complexes form an infinite three-dimensional supramolecular structure involving intermolecular C–H···Br hydrogen bonds
and π···π stacking interactions between the metal chelate rings and aromatic rings. Substituent effects in the two complexes
are discussed. 相似文献
16.
The triethanolamine complexes, [M(tea)2]sq·nH2O, (n=2 for Co(II), n=0 for Ni(II), Cu(II) and n=1 for Cd(II), tea=triethanolamine, sq2−=squarate), have been synthesized and characterized by elemental analyses, magnetic susceptibility and conductivity measurements,
UV-Vis and IR spectra, and thermal analyses techniques (TG, DTG and DTA). The Co(II), Ni(II) and Cu(II) complexes possess
octahedral geometry, while the Cd(II) complex is monocapped trigonal prismatic geometry. Dianionic squarate behaves as a counter
ion in the complexes. The thermal decomposition of these complexes takes place in three stages: (i) dehydration, (ii) release of the tea ligands and (iii) burning of organic residue. On the basis of the first DTGmax of the decomposition, the thermal stability of the anhydrous complexes follows the order: Ni(II), 289°C>Co(II), 230°C>Cu(II),
226°C>Cu(II), 170°C in static air atmosphere. The final decomposition products — the respective metal oxides — were identified
by FTIR spectroscopy. 相似文献
17.
Kateryna E. Gubina Oleg A. Maslov Elizaveta A. Trush Victor A. Trush Vladimir A. Ovchynnikov Svetlana V. Shishkina Vladimir M. Amirkhanov 《Polyhedron》2009,28(13):2661-2666
This paper presents examples of mixed-ligand Co(II), Cu(II), Ni(II) and Mn(II) complexes, with a distorted octahedral coordination geometry, with 2,2′-dipyridyl or 1,10-phenanthroline and phosphortriamide ligands. The complexes of the general type ML2·Lig (where M = Co(II), Cu(II), Ni(II), Mn(II); L− = {Cl3C(O)NP(O)R2}− (R = NHBz, NHCH2CHCH2, NEt2); Lig = 2,2′-dipyridyl or 1,10-phenanthroline) were synthesised and characterised by means of X-ray diffraction, IR and UV–Vis spectroscopy. The phosphortriamide ligands are coordinated via oxygen atoms of phosphoryl and carbonyl groups involved in six-membered metal cycles. The additional ligands 2,2′-dipyridyl or 1,10-phenanthroline are coordinated to the central atom, forming five-membered cycles. 相似文献
18.
New divalent transition metal 3,5-pyrazoledicarboxylate
hydrates of empirical formula Mpz(COO)2(H2O)2,
where M=Mn, Co, Ni, Cu, Zn and Cd (pz(COO)2=3,5-pyrazoledicarboxylate),
metal hydrazine complexes of the type Mpz(COO)2N2H4
where M=Co, Zn or Cd and Mpz(COO)2nN2H4·H2O,
where n=1 for M=Ni
and n=0.5 for M=Cu
have been prepared and characterized by physico-chemical methods. Electronic
spectroscopic data suggest that Co and Ni complexes adopt an octahedral geometry.
The IR spectra confirm the presence of unidentate carboxylate anion (Δν=νasy(COO–)–νsym(COO–)>215
cm–1) in all the complexes and bidentate
bridging hydrazine (νN–N=985–950 cm–1)
in the metal hydrazine complexes. Both metal carboxylate and metal hydrazine
carboxylate complexes undergo endothermic dehydration and/or dehydrazination
followed by exothermic decomposition of organic moiety to give the respective
metal oxides as the end products except manganese pyrazoledicarboxylate hydrate,
which leaves manganese carbonate. X-ray powder diffraction patterns reveal
that the metal carboxylate hydrates are isomorphous as are those of metal
hydrazine complexes of cobalt, zinc and cadmium. 相似文献
19.
Complexation of U(VI), Ce(III) and Nd(III) with acetohydroxamic acid in perchlorate aqueous solution
Dong-Yong Chung Eun-Kyoung Choi Eil-Hee Lee Kwang-Wook Kim 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):315-319
Complexes of UO2
2+, Ce3+ and Nd3+ (M) with acetohydroxamic acid (AHA or L) in an aqueous solution have been investigated by the pH-spectral titration method
at 25 °C in an aqueous medium of 1.0 M NaClO4 ionic strength. Cerium(III) and neodymium(III) form [ML]2+, [ML2]+, [ML3] complexes with acetohydroxamic acid, while in case of UO2
2+ form [UO2L]+, [UO2L2] complexes with acetohydroxamic acid. Data processing with SQUAD program calculates the best values for the stability constants
from pH-spectrophotometric titration data. The protonation constant obtained was pK1 = 9.15 ± 0.04 at 25 °C. The stability constants for acetohydroxamic acid with UO2
2+, Ce3+ and Nd3+ were β1 = 7.22 ± 0.011, β2 = 14.89 ± 0.018 for UO2
2+ and β1 = 5.05 ± 0.062, β2 = 10.60 ± 0.076, β3 = 16.23 ± 0.088 for Ce3+ and β1 = 5.90 ± 0.028, β2 = 12.22 ± 0.038, β3 = 18.58 ± 0.042 for Nd3+, respectively. 相似文献
20.
G. J. Kharadi 《Journal of Thermal Analysis and Calorimetry》2012,107(2):651-659
Four copper(II) new mix ligand complexes of the coumarin derivative (A1 = 7-hydroxy-10,11-dihydroindeno[5,4-c]chromen-6(9H)-one, A2 = 2-bromo-7-hydroxy-10,11- dihydroindeno[5,4-c]chromen-6(9H)-one, A3 = 7-hydroxy-4-methoxy-10,11-dihydroindeno[5,4-c]chromen-6(9H)-one, and A4 = 5-hydroxy-8,9-dihydrobenzo[f]indeno[5,4-c]chromen-4(7H)-one) and 1,10-Phenanthroline have been synthesized. The structural
interpretations were confirmed from elemental analyses, magnetic susceptibility and FAB mass spectral, as well as from IR
spectral studies. From the analytical, spectroscopic, and thermal data, the stoichiometry of the mentioned complexes was found
to be 1:1:1 (coumarin ligand:copper metal:1,10-Phenanthroline). The thermal stabilities of these complexes were studied by
thermogravimetric (TG/DTG) and the decomposition steps of these four complexes are investigated. Kinetic parameters such as
order of reaction (n) and the energy of activation (E
a) were calculated using Freeman–Carroll method. The pre-exponential factor (A), the activation entropy (S*), the activation enthalpy (H*), and the free energy of activation (G*) were calculated using Horowitz–Matzger equations. Based on the E
a values, the thermal stabilities of complexes in the decreasing order are Cu(II)-2 > Cu(II)-3 > Cu(II)-4 > Cu(II)-1. 相似文献