共查询到20条相似文献,搜索用时 15 毫秒
1.
E. Yu. Fursova O. V. Kuznetsova G. V. Romanenko A. S. Bogomyakov V. I. Ovcharenko 《Russian Chemical Bulletin》2010,59(2):337-341
The heterospin mixed-ligand complex [Ni6(OH)4Piv4(hfac)4(NIT-Ph)2] (1) (NIT-Ph is 4,4,5,5-tetramethyl-2-phenyl-4,5-dihydro-1H-imidazol-1-oxyl 3-oxide, hfac is hexafluoroacetylacetonate, and Piv is pivalate) was synthesized. The method for the synthesis
of complex 1 is based on the replacement of acetone molecules in the hexanuclear complex containing the hexafluoroacetylacetonate and
pivalate ligands [Ni6(OH)4Piv4(hfac)4(Me2CO)4] by NIT-Ph molecules. Two monodentate NIT-Ph molecules replace four acetone molecules, because the coordination of the O
atom of the nitroxide group results in the blocking of one of the positions in the coordination environment of NiII the access to which is hindered by the phenyl ring of NIT-Ph. As a result, these ions are in a square-pyramidal environment
unusual of NiII. In the low-temperature range, the dependence of the magnetization of 1 on the magnetic field is described by the Brillouin function. The reaction of [Ni6Piv4(hfac)4(OH)4(Me2CO)4] with the nitronyl nitroxide radicals 4,4,5,5-tetramethyl-2-(4-pyridyl)-4,5-dihydro-1H-imidazol-1-oxyl 3-oxide (NIT-p-Py) or 4,4,5,5-tetramethyl-2-(1-methyl-1H-imidazol-5-yl)-4,5-dihydro-1H-imidazol-1-oxyl 3-oxide (NIT-Iz) containing the pyridine or 1-methylimidazol-5-yl substituent, respectively, in the side
chain is accompanied by the decomposition of the polynuclear fragment and affords the mononuclear complexes Ni(hfac)2(NIT-p-Py)2 and Ni(hfac)2(NIT-Iz)2, respectively. The reaction of 4,4,5,5-tetramethyl-2-(1-methyl-1H-imidazol-5-yl)-4,5-dihyd-ro-1H-imidazol-1-oxyl (Im-Iz), which is the imine analog of NIT-Iz, with [Ni6Piv4(hfac)4(OH)4(Me2CO)4] afforded the decanuclear complex [Ni10(OH)8Piv4(hfac)8(Im-Iz)2(H2O)6]. The molecular and crystal structures of all heterospin compounds were determined, and the magnetic properties of all compounds
were investigated in the 2–300 K temperature range. 相似文献
2.
O. V. Kuznetsova E. Yu. Fursova V. I. Ovcharenko G. V. Romanenko A. S. Bogomyakov 《Russian Chemical Bulletin》2008,57(10):2198-2200
A dodecanuclear complex [Ni12Piv10(hfac)6(OH)8(EtOH)6]·C6H14 was isolated from various synthetic systems simultaneously containing NiII and the pivalate and hexafluoro-acetylacetonate anions. The structure of this complex was determined and the magnetic properties
were investigated. The use of EtOH as the solvent or the presence of EtOH in the reagents is the decisive factor for the formation
of this complex. 相似文献
3.
Reactions of Pentapseudohalonitrosyl ferrate(II) with Morpholinobenzyl benzamide(MBB) and Piperidinobenzyl benzamide(PBB)
formed complexes of the type, [Fe(X)3(NO)(L–L)] where X = CN−, NCO− and N
3
−
and L–L = Morpholinobenzyl benzamide(MBB) and Piperidinobenzyl benzamide(PBB). These compounds have been characterized
by various physico-chemical techniques such as elemental analysis, molar conductance, magnetic susceptibility measurements,
i.r., electronic spectra, thermal gravimetric analysis. The molecular modeling Studies have been carried out for structural
analysis for some of the complexes have been carried out using Hyperchem release 7.52 professional version. 相似文献
4.
E. Yu. Fursova O. V. Kuznetsova V. I. Ovcharenko G. V. Romanenko A. S. Bogomyakov 《Russian Chemical Bulletin》2008,57(6):1198-1205
The reaction of NiCl2 with excess potassium pivalate (KPiv) in ethanol affords the chainpolymeric compound KNi4(Piv)7(OH)2(EtOH)6. In the solid compound, the tetranuclear nickel fragments alternate with potassium atoms. The use of KNi4(Piv)7(OH)2(EtOH)6 in the reaction with Ni(hfac)2 (hfac is the hexafluoroacetylacetonate anion) gave the first polynuclear mixed-ligand complexes [K2Ni6(Piv)7(hfac)3(OH)4(HPiv)2(Me2CO)2]·1.5C7H16, [Ni6(Piv)4(hfac)4(OH)4(Me2CO)4], [K2Ni8(Piv)8(hfac)4(OH)6(H2O)2(Me2CO)6], [Ni8(Piv)10(hfac)2(OH)2(MeO)2(MeOH)2(HPiv)2]·C6H14, and [Ni16(Piv)10(hfac)6(OH)10(MeO)6(MeOH)8(H2O)6]·C6H14 containing both Piv and hfac as the anionic ligands. The molecular and crystal structures of all these compounds were established,
and their magnetic properties were studied. All solids containing simultaneously Piv and hfac ligands tend to undergo ferromagnetic
ordering with decreasing temperature. The solid [Ni8(Piv)10(hfac)2(OH)2(MeO)2(MeOH)2(HPiv)2]·C6H14 undergoes cooperative magnetic ordering below T
c (2.5 K).
Dedicated to the 90th anniversary of the L. Ya. Karpov Institute of Physical Chemistry.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1175–1182, June, 2008. 相似文献
5.
M. A. Kiskin A. A. Sidorov G. G. Aleksandrov Yu. G. Shvedenkov V. N. Ikorskii V. M. Novotortsev I. L. Eremenko I. I. Moiseev 《Russian Chemical Bulletin》2005,54(9):2211-2214
The interaction of [K2FeIII
4(O)2(OOCCMe3)10(HOOCCMe3)2(H2O)2]n with 2-pyridinecarboxaldehyde results in a mixed-valence complex FeIIFeIII
3(μ3-O)2(μ2-OOCCMe3)7L2··2.5MeCN·3H2O (L = 2-NC5H4COOH0.75K0.25). The structure of the complex was established by X-ray analysis. The magnetic properties of the complex were studied.
Dedicated to Academician A. L. Buchachenko on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2145–2148, September, 2005. 相似文献
6.
E.?M.?Zueva E.?V.?Tretyakov S.?V.?Fokin G.?V.?Romanenko A.?O.?Tkacheva A.?S.?Bogomyakov O.?V.?Petrova B.?A.?Trofimov R.?Z.?Sagdeev V.?I.?Ovcharenko
5-Formylpyrrolyl-substituted nitronyl and imino nitroxide radicals HL1 and HL2 were synthesized. Their solid phases are formed by packing pairs of the molecules. In the {HL1...HL1} pairs, the dominant interaction is the ferromagnetic exchange with J/kB = 8.8 K (Hamiltonian \(H = 2J\left( {\overrightarrow {{s_1}} \overrightarrow {{s_2}} } \right)\)). The ferromagnetic exchange occurs also in the heterospin molecules [Ni(L1)2], [Cu(L1)2], and [Ni(L2)2(MeOH)2]. In the complexes [Ni(L1)2] and [Cu(L1)2], a small change in the mutual orientation of the coordinated ligands has a considerable effect on the value and the sign of the energy of exchange interactions between the unpaired electrons of the metal ion and paramagnetic ligands. 相似文献
7.
E. Yu. Fursova O. V. Kuznetsova V. I. Ovcharenko G. V. Romanenko A. S. Bogomyakov M. A. Kiskin I. L. Eremenko 《Russian Chemical Bulletin》2007,56(9):1805-1808
A method was developed for the synthesis of mixed-metal heterospin compounds with the direct coordination of the nitroxide
fragment based on the replacement of acetonitrile molecules in the heterotrinuclear complex [Co2Gd(NO3)Piv6(CH3CN)2] with nitroxide molecules. The molecular and crystal structure of the heterospin mixed-ligand heterotrinuclear CoII, GdIII, CoII complex [Co2Gd(NO3)Piv6(NIT-Me)2], where NIT-Me is stable nitronyl nitroxide, was established. The magnetic properties of this complex were investigated in
the temperature range of 2–300 K. The coordination of nitroxide groups to CoII ions is responsible for strong exchange interactions between the unpaired electrons in the exchange clusters {>-·O-CoII}, resulting in the virtually complete spin coupling between each coordinated >N-·O group and one of the unpaired electrons
of each CoII ion at temperatures below 200 K.
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1742–1745, September, 2007. 相似文献
8.
O. V. Kuznetsova E. Yu. Fursova G. A. Letyagin G. V. Romanenko V. I. Ovcharenko 《Russian Chemical Bulletin》2018,67(7):1202-1205
Hydrolysis of [M4(hfac)4(MeO)4(MeOH)4] (М = Сo, Ni and hfac is hexafluoroacetylaceton ate) is a convenient way of obtaining polynuclear complexes [Ni7(hfac)6(OH)8(H2O)6]?2H2O, [Co12(hfac)10(OH)14(H2O)8]?2H2O?2MePh, [Co12(hfac)10(OH)14(H2O)4(Me2CO)4]?3PhMe, and [Co12(hfac)10(OH)14(H2O)6(Me2CO)2]?2H2O?2Me2CO, whose structures were confirmed by X-ray analysis. 相似文献
9.
The heteronuclear complex [Fe4Li2(O)2(Piv)10(H2O)2] (1, Piv is the pivalic acid anion) was obtained by refluxing FeIII pivalates with LiI pivalates in toluene and isolated as the 1?PhCH3 solvate with a toluene molecule. According to X-ray diffraction data, complex 1 contains the {Fe4Li2O2} core. The Mössbauer spectroscopy data indicate that the core comprises para magnetic FeIII ions in the high-spin state located in the symmetric octahedral environment of oxygen atoms. Thermolysis of 1 studied by simultaneous thermal analysis demonstrated thermal stability of the complex up to 225 °С. The main end product of thermolysis at 600 °С is the mixed oxide LiFe5O8. 相似文献
10.
Bipyrimidines have been chosen as (N∧N)(N∧N) bridging ligands for connecting metal centers. IrIII-LnIII (Ln = Nd, Yb, Er) bimetallic complexes [Ir(dfppy)2(μ-bpm)Ln(TTA)3]Cl were synthesized by using Ir(dfppy)2(bpm)Cl as the ligand coordinating to lanthanide complexes Ln(TTA)3·2H2O. The stability constants between Ir(dfppy)2(bpm)Cl and lanthanide ions were measured by fluorescence titration. The obvious quenching of visible emission from IrIII complex in the IrIII-LnIII (Ln = Nd, Yb, Er) bimetallic complexes indicates that energy transfer occurred from IrIII center to lanthanides. NIR emissions from NdIII, YbIII, and ErIII were obtained under the excitation of visible light by selective excitation of the IrIII-based chromophore. It was proven that Ir(dfppy)2(bpm)Cl as the ligand could effectively sensitize NIR emission from NdIII, YbIII, and ErIII. 相似文献
11.
Shashi Lata Bharati Pankaj Kumar Chaurasia Sudha Yadava 《Russian Journal of Inorganic Chemistry》2016,61(2):232-238
A novel series of MnIII complexes with 5,10,15,20-tetra(p-tolylporphine) and 1,6-diaminohexane has been synthesized. These complexes have been characterized by UV/Vis, IR, ESI-mass spectra, elemental analysis, conductivity and magnetic susceptibility measurements. These MnIII porphyrins exhibited a blue shift in soret band in comparison to non-metallated porphyrins. The molar conductance values of these complexes show their non-electrolytic nature in ethanol. The tentative structures have also been proposed. All the complexes have good level of water solubility due to which they may have medicinal as well as other valuable biological applications. 相似文献
12.
The reaction of equimolar amounts of ytterbocene (C5Me4H)2Yb(THF)2 and iminopyridine 2,6-Pri2C6H3N=CH(C5H4N) accompanied by the one-electron oxidation of the ytterbium ion produced the unique lanthanide complex (C5Me4H)2YbIII[2,6-Pri2-C6H3NCH(C5H4N)]–? with the iminopyridine radical-anionic ligand. The structure of the complex in the crystalline state was established by X-ray diffraction and its magnetic properties were studied in the temperature range of 1.8—300 K. 相似文献
13.
I. G. Fomina Zh. V. Dobrokhotova G. G. Aleksandrov M. L. Kovba V. I. Zhilov A. S. Bogomyakov V. M. Novotortsev I. L. Eremenko 《Russian Chemical Bulletin》2010,59(4):699-705
Joint thermolysis of the dinuclear pivalate complexes M2(μ-H2O)(μ-Piv)2(Piv)2(HPiv)4 (M = Co (1) and Ni (2), Piv- is the pivalate anion), in decane at 174 °C at the reactant ratio 1: 1 followed by treatment of the dry thermolysis product
with methanol afforded crystals of a new cocrystallization product of the molecules containing the heterometallic cubane-like
core M4(Co,Ni)O4. According to the X-ray diffraction data and the results of magnetic measurements, inductively coupled plasma atomic emission
spectrometry (ICP-AES), and investigations of the solid-state thermal decomposition products, the isolated cocrystallization
product has the general formula [Co1.6Ni2.4(μ3-OMe)4(μ2-Piv)2(pg2 -Piv)2(MeOH)4] ·4MeOH (3·4MeOH). Thermolysis of the crystals of the solvate 3·4MeOH is a destructive process accompanied by the intramolecular
redox reaction. A mixture of metallic Ni and cobalt oxide (CoO) are the final solid decomposition products of 3 · 4MeOH in
an argon atmosphere, whereas a mixture of the phases NiO, Co3O4, and NiCo2O4 is formed in air. 相似文献
14.
V. I. Ovcharenko S. V. Fokin G. V. Romanenko A. S. Bogomyakov D. S. Yachevskii D. L. Chizhov V. N. Charushin O. N. Chupakhin 《Russian Chemical Bulletin》2010,59(6):1162-1174
Dinuclear heterospin complexes of CuII and MnII 1,1,1,7,7,7-hexafluoroheptane-2,4,6-trionates ([Cu2L2] and [Mn2L2], respectively) with nitronyl nitroxides 2-R-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide 1-oxyls (NIT-R, R = H, Me, Et, m-C5H4N, m-NCC6H4, p-NCC6H4, PzMe) and the diradical NIT-Pz-(CH2)4-Pz-NIT (Pz is 1,4-pyrazolylene) were synthesized and structurally characterized. In the complexes under study, the CuII atom
tends to have the square-pyramidal coordination environment, and the MnII atom is in an octahedral environment. The magnetochemical
investigation of the compounds in the temperature range of 2–300 K showed that the antiferromagnetic exchange coupling dominates
in the [Cu2L2] molecules, whereas this coupling in [Mn2L2] is manifested in the experimental plot μeff(T) at T < 100 K. The magnetic properties of the heterospin complexes of [Cu2L2] with NIT-R are also determined by the intramatrix antiferromagnetic exchange coupling. For the complexes of [Mn2L2] with NIT-R, the coordination mode of the nitroxide plays a decisive role. 相似文献
15.
A. N. Bilyachenko A. A. Korlyukov M. M. Levitskii M. Yu. Antipin B. G. Zavin 《Russian Chemical Bulletin》2007,56(3):543-545
The first cage-like ferrophenyl siloxane containing FeIII ions in different coordination spheres (four iron ions have a trigonal-bipyramidal coordination and two iron ions have a
distorted octahedral coordination) was synthesized by the exchange reaction of sodium phenylsilanolate with FeIII chloride. An exotic lantern-like structure is formed with the involvement of two metal oxide fragments Fe—O—Fe. The structure
of this compound was established by X-ray diffraction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 522–524, March, 2007. 相似文献
16.
1-(Pyridin-2-yl)-3-tosylurea(HL) and its two lanthanide complexes, LnL3 · H2O [Ln = Nd(1), Eu(2)], have been synthesized and characterized on the base of elemental analyses, molar conductivities, IR
spectra and thermal analyses. In addition, the DNA-binding properties of the two complexes have been investigated by absorption,
fluorescence and viscosity measurements. The experimental results indicated that the complex (1) and (2) can bind to DNA; the binding affinity of the complex (1) is higher than that of complex (2) and the intrinsic binding constants of complex (1) and complex (2) with DNA were 1.24 × 104
m
−1 and 8.7 × 103
m
−1, respectively. In addition, some factors that influence the fluorescent intensity were also discussed. 相似文献
17.
M. T. Metlin S. A. Ambrozevich S. S. Krasnosel’sky A. G. Vitukhnovsky S. E. Nefedov I. V. Taidakov 《Russian Chemical Bulletin》2016,65(7):1784-1789
The interaction of PrCl3 with 1,3-bis(1,3-dimethyl-1H-pyrazol-4-yl)-1,3-propanedione in aqueous ethanol in the presence of a base and 1,10-phenanthroline was studied. It was shown that the composition of the products was dependent on the reaction conditions. The solvate [Pr(L)3(Phen)]?3PriOH crystallizes in a monoclinic crystal system (P21/c space group, a = 12.2239(12) Å, b = 20.3403(19) Å, c = 26.134(3) Å, β = 102.380(2)° at 150 K). Absorption spectra of the complex in solution, as well as the spectra and the kinetic parameters of photo-luminescence were investigated. 相似文献
18.
Han-Bai Quan Liang-Bing Sheng Hua-Hong Zou Zi-Yuan Liu Dong-Cheng Liu Bo Li Man-Sheng Chen Fu-Pei Liang 《Journal of Cluster Science》2018,29(1):75-81
A series of twist linear tetranuclear 3d–4f Co 2 III Ln 2 III [Ln = Gd (1), Tb (2), Dy (3), Ho (4), Er (5)] complexes have been prepared under solvothermal conditions and structurally characterized with Schiff-base ligand 2-(((2-hydroxy-3-methoxyphenyl)methylene)amino)-2-(hydroxymethyl)-1,3-propanediol (H4L). The two central Co ions are linked by two alkoxyl oxygen atoms, and one Ln ion lying above and the other below the Co–Co dimer, form a twist linear array. The magnetic susceptibility studies reveal antiferromagnetic or ferromagnetic behaviour, whilst dynamic magnetic studies indicate no slow magnetic relaxation for these complexes. 相似文献
19.
Complexes of CrIII, MnII, ZnII & CdII with the polydentate carboxamide ligandN′, N′′-bis(3-carboxy-1-oxoprop-2-enyl) 2-Amino-N-arylbenzamidine (H2L) have been synthesized and characterized by elemental analyses, spectroscopic studies (Vibrational, electronic, ESR and
1H-NMR), magnetic susceptibility measurements, thermal studies and powder diffraction studies. The vibrational spectral data
are in agreement with coordination of amide and carboxylate oxygen of the ligands with the metal ions. The electronic spectra
indicates octahedral or tetrahedral geometry around the metal ions, has been supported by magnetic susceptibility measurements.
The results of electron spin resonance & 1H-NMR spectra have supported the results of other spectral techniques. Kinetic and thermodynamic parameters were computed
from the thermal data using Coats and Redfern method, which confirm first order kinetics. Powder diffraction determines the
cell parameters of the complexes. 相似文献
20.
Systems based on 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), iron(iii)—HEDP and manganese(ii)—iron(iii)—HEDP, were studied by pH-potentiometry combined with mathematical modeling and NMR. Diverse and highly stable heteronuclear iron manganese complexes were found to exist in the heteronuclear system. The formation of the MnH3L23–, FeMnH3L20, Fe2MnHL33–, and MnL2– complexes was established. The relaxation efficiency coefficient REC2 (relaxivity) of these complexes was evaluated at ~2000 mol–1 s–1 L. Therefore, these systems hold promise as MRI contrast agents. 相似文献