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1.
Wiesława Ferenc Agnieszka Walków-Dziewulska Maria Wojciechowska J. Sarzyński 《Journal of Thermal Analysis and Calorimetry》2006,86(2):359-364
Physico-chemical properties of 4-chloro-2-nitrobenzoates of Co(II),
Ni(II), and Cu(II) were studied. The complexes were obtained as mono- and
trihydrates with a metal ion to ligand ratio of 1:2. All analysed 4-chloro-2-nitrobenzoates
are polycrystalline compounds with colours depending on the central ions:
pink for Co(II), green for Ni(II), and blue for Cu(II) complexes. Their thermal
decomposition was studied only in the range of 293–523 K, because it
was found that on heating in air above 523 K 4-chloro-2-nitrobenzoates decompose
explosively. Hydrated complexes lose crystallization water molecules in one
step and anhydrous compounds are formed. The final products of their decomposition
are the oxides of the respective transition metals. From the results it appears
that during dehydration process no transformation of nitro group to nitrite
takes place. The solubilities of analysed complexes in water at 293 K are
of the order of 10–4–10–2
mol dm–3. The magnetic moment values of Co2+,
Ni2+ and Cu2+ ions in
4-chloro-2-nitrobenzoates experimentally determined at 76–303 K change
from 3.89 to 4.82 μB for Co(II) complex, from 2.25
to 2.98 μB for Ni(II) 4-chloro-2-nitrobenzoate,
and from 0.27 to 1.44 μB for Cu(II) complex. 4-chloro-2-nitrobenzoates
of Co(II), and Ni(II) follow the Curie–Weiss law. Complex of Cu(II)
forms dimer. 相似文献
2.
Wiesława Ferenc Beata Cristóvão Jan Sarzyński 《Journal of Thermal Analysis and Calorimetry》2010,101(2):761-767
5-Chloro-2-nitrobenzoates of Co(II), Ni(II) and Cu(II) having formulae Co(C7H3O4NCl)2·3H2O, Ni(C7H3O4NCl)2·3H2O and Cu(C7H3O4NCl)2·2H2O, were obtained as polycrystalline compounds. From the IR spectra analysis of complexes, sodium salt and according to the
spectroscopic criteria the carboxylate ions seem bidentate groups. The complexes of Co(II) and Cu(II) lose the water of crystallization
in one step at 363–523 K. The Ni(II) complex loses it in two stages in the ranges of 323–378 and 378–523 K, respectively.
The compounds follow the Curie–Weiss law. The magnetic moment values experimentally determined change from 4.53 to 4.55 μB for Co(II) complex, from 2.34 to 2.97 μB for Ni(II) 5-chloro-2-nitrobenzoate and from 1.80 to 1.90 μB for Cu(II) complex. 相似文献
3.
The complexes of 4-chloro-2-methoxybenzoic acid anion with Mn2+,
Co2+, Ni2+, Cu2+
and Zn2+ were obtained as polycrystalline solids
with general formula M(C8H6ClO3)2·nH2O and colours typical for M(II) ions (Mn – slightly pink, Co –
pink, Ni – slightly green, Cu – turquoise and Zn – white).
The results of elemental, thermal and spectral analyses suggest that compounds
of Mn(II), Cu(II) and Zn(II) are tetrahydrates whereas those of Co(II) and
Ni(II) are pentahydrates. The carboxylate groups in these complexes are monodentate.
The hydrates of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II), Cu(II)
and Zn(II) heated in air to 1273 K are dehydrated in one step in the range
of 323–411 K and form anhydrous salts which next in the range of 433–1212
K are decomposed to the following oxides: Mn3O4,
CoO, NiO and ZnO. The final products of decomposition of Cu(II) complex are
CuO and Cu. The solubility value in water at 293 K for all complexes is in
the order of 10–3 mol dm–3.
The plots of χM
vs.
temperature of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II)
follow the Curie–Weiss law. The magnetic moment values of Mn2+,
Co2+, Ni2+ and Cu2+
ions in these complexes were determined in the range of 76−303 K and
they change from: 5.88–6.04 μB for Mn(C8H6ClO3)2·4H2O, 3.96–4.75
μB for Co(C8H6ClO3)2·5H2O, 2.32–3.02 μB for Ni(C8H6ClO3)2·5H2O and 1.77–1.94
μB for Cu(C8H6ClO3)2·4H2O. 相似文献
4.
Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 3-methylglutarates were prepared as solids with general formula MC6 H8 O4 ×n H2 O, where n =0–8. Their solubilities in water at 293 K were determined (7.0×10−2 −4.2×10−3 mol dm−3 ). The IR spectra were recorded and thermal decomposition in air was investigated. The IR spectra suggest that the carboxylate
groups are mono- or bidentate. During heating the hydrated complexes lose some water molecules in one (Mn, Co, Ni, Cu) or
two steps (Cd) and then mono- (Cu) or dihydrates (Mn, Co, Ni) decompose to oxides directly (Mn, Cu, Co) or with intermediate
formation of free metals (Co, Ni). Anhydrous Zn(II) complex decomposes directly to the oxide ZnO.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
Wiesława Ferenc Beata Bocian J. Sarzyński 《Journal of Thermal Analysis and Calorimetry》2006,84(2):377-383
Four new complexes of 2,3,4-trimethoxybenzoic acid
anion with manganese(II), cobalt(II), nickel(II) and copper(II) cations were
synthesized, analysed and characterized by standard chemical and physical
methods. 2,3,4-Trimethoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II) are
polycrystalline compounds with colours typical for M(II) ions. The carboxylate
group in the anhydrous complexes of Mn(II), Co(II) and Ni(II) is monodentate
and in that of Cu(II) monohydrate is bidentate bridging one. The anhydrous
complexes of Mn(II), Co(II) and Ni(II) heated in air to 1273 K are stable
up to 505–517 K. Next in the range of 505–1205 K they decompose
to the following oxides: Mn3O4,
CoO, NiO. The complex of Cu(II) is stable up to 390 K, and next in the range
of 390–443 K it loses one molecule of water. The final product of its
decomposition is CuO. The solubility in water at 293 K is of the order of
10–3 mol dm–3
for the Mn(II) complex and 10–4 mol dm–3
for Co(II), Ni(II) and Cu(II) complexes. The magnetic moment values of Mn2+,
Co2+, Ni2+ and Cu2+
ions in 2,3,4-trimethoxybenzoates experimentally determined in the range of
77–300 K change from 5.64–6.57 μB (for Mn2+),
4.73–5.17 μB (for Co2+), 3.26–3.35 μB
(for Ni2+) and 0.27–1.42 μB (for Cu2+).
2,3,4-Trimethoxybenzoates of Mn(II), Co(II) and Ni(II) follow the Curie–Weiss
law, whereas that of Cu(II) forms a dimer. 相似文献
6.
Conditions for the preparation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)3,3-dimethylglutarates were investigated
and their quantitative composition, solubility in water at 293 K and magnetic moments were determined. IR spectra and powder
diffraction patterns of the complexes prepared with general formula MC7H10O4⋅nH2O (n=0−2) were recorded and their thermal decomposition in air were studied. During heating the hydrated complexes of Mn(II),Co(II),
Ni(II) and Cu(II) are dehydrated in one step and next all the anhydrous complexes decompose to oxides directly (Mn, Co, Zn)
or with intermediate formation free metal (Ni,Cu) or oxocarbonates (Cd). The carboxylate groups in the complexes studied are
bidentate. The magnetic moments for the paramagnetic complexes of Mn(II), Co(II), Ni(II) and Cu(II)attain values 5.62, 5.25,
2.91 and 1.41 M.B., respectively.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
7.
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
8.
Elena A. Reshetnyak Nataliia V. Ivchenko Nataliya A. Nikitina 《Central European Journal of Chemistry》2012,10(5):1617-1623
Photometric determination of aqueous Co(II), Cu(II), Ni(II) and Fe(III) was performed using indicator films prepared by immobilization
of 1-nitroso-2-naphthol-3,6-disulfonic acid disodium salt (NRS) into hardened photographic film. Immobilization was based
on electrostatic interaction of reagent and metal complexes with the gelatin. The isoelectric point pH of hardened gelatin
(4.46±0.04) was evaluated by viscometry. Co(II), Fe(III), Ni(II) form 1:3 complexes with NRS in gelatin at pH 2 and Cu(II)
forms 1:2 complexes. Their log β′ values were: Co-6.7, Fe-8.6, Cu-8.0, and Ni-6.4. The absorption maxima were: 370nm for NRS,
and 430nm, 470nm, 495nm and 720nm for complexes of Co(II), Ni(II), Cu(II) and Fe(III). An algorithm for their simultaneous
determination using the indicator films was developed. The detection limits were: clim(Co2+) = 0.45×10−5 M, clim(Fe3+) = 0.50×10−5 M, clim(Cu2+) = 0.67×10−5 M, clim(Ni2+) = 0.75×10−5 M,; and their sum clim(ΣMn+) = 0.82×10−5 M.
相似文献
9.
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
10.
A novel macrocyclic tetradentate ligand 1,5,8,12-tetraaza-2,4,9,11-tetraphenyl-6,7:13,14-dibenzocyclohexadeca- 1,4,8,11-tetraene
(L) has been synthesized. Cobalt(II), nickel(II), and copper(II) complexes of this ligand have been prepared and characterized
by elemental analysis, molar conductance measurements, magnetic susceptibitity measurements, and mass, IR, electronic, and
ESR spectral studies. The molar conductance measurements correspond to a nonelectrolytic nature for all the complexes, which
can be formulated as [M(L)X2] (where M = Co(II), Ni(II), and Cu(II); X = Cl− and NO3−). On the basis of IR, electronic, and ESR spectral studies, an octahedral geometry has been assigned to the Co(II) and Ni(II)
complexes, whereas a tetragonal geometry was found for the Cu(II) complexes. The investigated compounds and uncomplexed metal
salts and the ligands were tested against bacterial species like Sarcina lutea, Escherchia coli, and Staphylococcus aureus. The metal complexes have higher activity than the free ligand and metal salts.
The text was submitted by the authors in English. 相似文献
11.
Conditions for the preparation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 4-methylphthalates were investigated and
their composition, solubility in water at 295 K and magnetic moments were determined. IR spectra and powder diffraction patterns
of the complexes prepared with molar ratio of metal to organic ligand of 1.0:1.0 and general formula: M [ CH3C6H3(CO2)2]·nH2o (n=1-3) were recorded and their decomposition in air were studied. During heating the hydrated complexes are dehydrated in one
(Mn, Co, Ni, Zn, Cd) or two steps (Cu) and next the anhydrous complexes decompose to oxides directly (Cu, Zn), with intermediate
formation of carbonates (Mn, Cd), oxocarbonates (Ni) or carbonate and free metal (Co). The carboxylate groups in the complexes
studied are mono- and bidentate (Co, Ni), bidentate chelating and bridging (Zn) or bidentate chelating (Mn, Cu, Cd). The magnetic
moments for paramagnetic complexes of Mn(II), Co(II), Ni(II) and Cu(II) attain values 5.92, 5.05, 3.36 and 1.96 M.B., respectively.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
Crystal structure and biological activities of water-soluble nickel(II) and copper(II) complexes of a Schiff-base derived from paeonol 总被引:1,自引:0,他引:1
Water-soluble Ni(II) and Cu(II) complexes of a flexible Schiff-base ligand have been synthesized, and the Ni(II) complex was
characterized by X-ray crystallography. The interactions of the two complexes with calf thymus DNA were investigated by spectroscopic
and viscosity measurements in water. The results suggest that the two complexes bind to DNA within the groove. Antioxidant
experiments against OH• and O2−• show that these two complexes have excellent ability to scavenge O2−•, and the Cu(II) complex exhibits better activity than the Ni(II) complex. 相似文献
13.
Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 2,5-dichlorobenzoates were prepared and their compositions and solubilities in water
at 295 K were determined. The IR spectra and X-ray diffractograms of the obtained complexes were recorded. The complexes of
Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) were obtained as solids with a 1:2 molar ratio of metal to organic ligand and different
degrees of hydration. When heated at a heating rate of 10 K min-1, the hydrated complexes lose some (Co, Zn) or all (Ni, Cu, Cd) of the crystallization water molecules and then decompose
to oxide MO (Co, Ni) or gaseous products (Cu, Zn, Cd). When heated at a heating rate of 5 K min-1, the complexes of Ni(II) and Cu(II) lose some (Ni) or all (Cu) of the crystallization water molecules and then decompose
directly to MO.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
Cyclic voltammetry (CV) and square-wave voltammetry (SWV) techniques have been used to study the binary complexes of Co(II),
Ni(II) and Cu(II) with sulfamethazine (SMZ) at a static mercury drop electrode (SMDE) in 0.04 M Britton-Robinson (B-R) buffer.
SMZ gave three peaks at 0.01, −1.32 and −1.55 V. Cu(II)-SMZ complex was recognized by a cathodic peak at −0.38 V. Ni(II)-SMZ
complex was reduced at more positive potential (−0.77 V) than that of the hydrated Ni(II) ions (−1.08 V). Co(II)-SMZ complex
is investigated at pH 7 and 8. The Co(II) complex at pH 7 is appeared as a shoulder at −1.19 V, whereas this peak becomes
a well-separated form at pH 8. The study indicated that the SMZ serves as a catalyst in the reduction of Co(II) and Ni(II)
ions. From electronic spectra data of the complexes, their stoichiometries of 1: 2 (metal-ligand) in aqueous medium are determined.
The stability constants of the complexes are in agreement with the Irwing-Williams series (Co < Ni < Cu). 相似文献
15.
Agnieszka Dziewulska-Kułaczkowska 《Journal of Thermal Analysis and Calorimetry》2010,101(3):1019-1026
The complexes Mn(II), Co(II), Ni(II) and Zn(II) with 4-oxo-4H-1-benzopyran-3-carboxaldehyde were synthesized and characterized
by elemental analysis, infrared and UV spectroscopy, X-ray diffraction patterns, magnetic susceptibility, thermal gravimetric
analysis, conductivity and also solubility measurements in water, methanol and DMF solution at 298 K. They are polycrystalline
compounds with various formula and different ratio of metal ion:ligand. Their formula are following: [MnL2(H2O)](NO3)2·2H2O, [CoL2](NO3)2·3H2O, [NiL2](NO3)2·3H2O, [CuL2](NO3)2·H2O and [ZnL3](NO3)2, where L = C10H6O3. The coordination of metal ions is through oxygen atoms present in 4-position of γ-pyrone ring and of aldehyde group of ligand.
Chelates of Mn(II), Co(II), Ni(II) and Cu(II) obey Curie–Weiss law and they are high-spin complexes with the weak ligand fields.
The thermal stability of analyzed complexes was studied in air at 293–1,173 K. On the basis of the thermoanalytical curves,
it appears that thermal stability of anhydrous analysed chelates changed following: Cu (423 K) < Zn (438 K) ~ Co (440 K) < Ni
(468 K). The gaseous products of thermal decomposition of those compounds in air atmosphere are following: CO2, CO, NO2, N2O, hydrocarbons and in case of hydrates also water. The molar conductance data confirm that the all studied complexes are
1:2 electrolytes in DMF solution. 相似文献
16.
New mixed-ligand complexes with empirical formulae M(4-bpy)L2·1.5H2O (M(II)=Mn, Co), Ni(4-bpy)2L2 and Cu(4-bpy) L2·H2O (where: 4-bpy=4,4'-bipyridine, L=CC L2HCOO-) have been isolated in pure state. The complexes have been characterized by elemental analysis, ir spectroscopy, conductivity
(in methanol, dimethylformamide and dimethylsulfoxide solutions) and magnetic and x-ray diffraction measurements. The Mn(II)
and Co(II) complexes are isostructural. The way of metal-ligand coordinations discussed. the ir spectra suggest that the carboxylate
groups are bonded with metal(II) in the same way (Ni, Cu) or in different way (Mn, Co). The solubility in water is in the
order of 19.40·10-3÷1.88·10-3ł mol dm-3ł. During heating the hydrate complexes lose all water in one step. The anhydrous complexes decompose to oxides via several
intermediate compounds. A coupled TG-MS system was used to analyse the principal volatile products of obtained complexes.
The principal volatile products of thermal decomposition of complexes in air are: H2O2
+, CO2
+, HCl+, Cl2
+, NO+ and other.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Ferenc W. Bocian B. Walków-Dziewulska A. 《Journal of Thermal Analysis and Calorimetry》2004,76(1):179-192
The conditions of the formation of yttrium(III) and lanthanide(III) 2-chloro-5-nitrobenzoates were studied and their quantitative
composition and solubilities in water at 298 K were determined. The compounds are dihydrates and their solubilities are of
the order of 10-3 mol dm-3. The FTIR, FIR and X-ray spectra for the complexes were recorded. All complexes are crystalline compounds. Their thermal
decomposition was studied only in the range 293-523 K since on heating above 523 K the complexes decompose explosively. Hydrated
2-chloro-5-nitrobenzoates of rare earth elements lose two crystallization water molecules in one step. The enthalpy of dehydration
process was established and the magnetic moments of the complexes were determined in the range 77-300 K. The compounds obey
the Curie-Weiss law. The 4f electrons do not participate in the formation of the Ln-O bonds.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
18.
Waqas Jamil Sorath Solangi Muhammad Ali Khalid Muhammad Khan Muhammad Taha Muhammad Yar Khuhawar 《Arabian Journal of Chemistry》2019,12(8):2262-2269
2-Hydroxy salicylhydrazide isatin hydrazone (L) and its Mn (II), Co (II), Ni (II), Cu (II), and Zn (II), metal complexes were synthesized. 1H NMR, UV–Vis, IR spectroscopy and elemental (CHN/S) analysis techniques were applied for characterization. TG/DTA techniques revealed that all the synthetic compounds are thermally stable up to 300 °C. They were found non-electrolytes in nature. Furthermore, all these complexes were evaluated for antiglycation and DPPH radical scavenging activities. They showed varying degree of activity with IC50 values between 168.23 and 269.0 μM in antiglycation and 29.63–57.71 μM in DPPH radical scavenging activity. Mn (II), Co (II), Ni (II), Cu (II), and Zn (II), metal complexes showed good antiglycation as well as DPPH radical scavenging activity. The IC50 values for antiglycation activity are 168.23 ± 2.37, 234.27 ± 4.33, 257.1 ± 6.43, 267.7 ± 8.43, 269.0 ± 8.56 Ni for Co, Zn, Mn, Cu, and Ni complexes, respectively, while IC50 value were found to be 29.63 ± 2.76, 31.13 ± 1.41, 35.16 ± 2.45, 43.53 ± 3.12, 57.71 ± 2.61 μM for Cu, Zn, Mn, Co and Ni complexes, respectively, for DPPH radical scavenging activity. These synthesized metal complexes were found to be better active than standards Rutin (IC50 = 294.46 μM) for anti-glycation, and tert-butyl-4-hydroxyanisole (IC50 = 44.7 μM) for DPPH radical scavenging activity. 相似文献
19.
Spectral,
magnetic and thermal investigations of some d-electron
element 3-methoxy-4-methylbenzoates
Conditions
for the preparation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 3-methoxy-4-methylbenzoates
were investigated and their quantitative composition and magnetic moments
were determined. The IR spectra and powder diffraction patterns of the complexes
prepared of general formula M(C9H9O3)2·nH2O (n=2
for Mn, Co n=1 for Ni, Cu, n=0
for Zn, Cd) were prepared and their thermal decomposition in air was studied.
Their solubility in water at 293 K is of the order 10–2
(Mn)–10–4 (Cu) mol dm–3.
IR spectra of the prepared 3-methoxy-4-methylbenzoates suggest that carboxylate
groups are bidentate bridging. The magnetic moments for the paramagnetic complexes
of Mn(II), Co(II), Ni(II) and Cu(II) attain values 5.50, 4.45, 3.16 and 1.79
B. M., respectively. During heating the hydrated complexes lose crystallization
water molecules in one step and then the anhydrous complexes decompose directly
to oxides MO and Mn3O4. Only Co(II) complex decomposes to Co3O4
with intermediate formation CoO. 相似文献
20.
Sandra S. Konstantinović Blaga C. Radovanović Aleksandra Krklješ 《Journal of Thermal Analysis and Calorimetry》2007,90(2):525-531
The isatin-β-thiosemicarbazone (ITC) complexes of Co(II), Ni(II), Cu(II), Zn(II), Hg(II) and Pd(II) were prepared and characterized
by elemental analysis, as well as molar conductivity, magnetic susceptibility, FTIR, UV-Vis and 1H NMR spectroscopic methods. The complexes were also studied for its thermal stability. They all behaviour as anhydrous complexes
and its thermolysis passes through the stages of deamination (517–547 K) and complete thermal decomposition (619–735 K). 相似文献