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1.
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
2.
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
3.
Mihaela Vlassa George Borodi Gabriela Blăniţa Ileana Cojocaru Mircea Vlassa Cristian Silvestru 《Central European Journal of Chemistry》2011,9(2):224-231
Reaction of [CuII(cyclam)](ClO4)2 or [NiII(cyclam)](ClO4)2 in DMF with aqueous 4-hydroxy-3-(4-sulfonato-1-naphthylazo)naphthalen-1-sulfonate disodium salt (carmoisine) yielded coordination
polymers {[CuII(cyclam)](carmoisine dianion)(H2O)5}n and powder {[NiII(cyclam)](carmoisine dianion)}n, respectively (cyclam = 1,4,8,11-tetrazacyclotetradecane). They were characterized by powder X-ray diffraction, IR, Raman
spectrometry and TGA. 相似文献
4.
P. Muralidhar Reddy Adapa V. S. S. Prasad Vadde Ravinder 《Transition Metal Chemistry》2007,32(4):507-513
Macrocyclic CuII compounds of the type Cu(L4)Cl2 (where L4 = N4 or N2O2 donor macrocyclic ligand) have been synthesized by treating the corresponding macrocycles with copper chloride in methanol.
These compounds were characterized with the help of elemental analysis, i.r., mass, ESR, electronic spectra, conductance,
magnetic and thermal studies. Distorted octahedral geometry has been proposed for all of these compounds. These compounds
were found to be efficient in the catalytic oxidation of ascorbic acid and the percentage yields of oxidation products were
determined spectrophotometrically. The biological activities of these compounds have been tested against gram +ve and gram
−ve bacteria and found to be more active when compared with commercially available antibacterials like streptomycin and ampicillin. 相似文献
5.
The effect of ligand environment on the mechanism of enantiomerization of BeII, ZnII, and CuII bischelate aminovinylketonate complexes was studied by the B3LYP/6-311++G(d,p) method. Substituents at the nitrogen atom
(R = H, Me, Pri) significantly affect the mechanism of enantiomerization. In the beryllium complexes, the diagonal twist mechanism is changed
to the dissociation mechanism. In the zinc complexes, only the diagonal twist mechanism is realized. The barrier to reaction
monotonically increases with the size of the substituent. In the copper complexes, the effect of substituents manifests itself
in the change in the relative stabilities of different forms. At R = H, the square-planar form is more stable, while the tetrahedral
configuration is favorable at R = Pri. For the CuII complex with R = Me, the energy difference between two forms is less than 1 kcal mol-1, which leads to stabilization of the squareplanar structure in the solid state, whereas the tetrahedral form is more stable
in solution. 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.
Schiff bases derived from 4-aminomethylcarbostyril and their transition metal complexes with CoII, NiII, CuII and ZnII have been synthesized and characterized by elemental analysis, molar conductance, magnetic susceptibilities electronic, IR,
PMR, ESR, FAB-Mass and thermal studies. From the above spectral studies it is concluded that the ligands of 4-substituted
carbostyril Schiff bases, viz, salicylidene 4-aminomethylcarbostyril (SAMC); o-vanillinsalicylidene 4-aminomethylcarbostyril (VAMC) and 5′ chlorosalicylidene 4-aminomethylcarbostyril (CSAMC) act as bidenate
molecules coordinating through azomethine nitrogen and phenolic oxygen. The ligands and their metal complexes have been screened
in vitro for antibacterial, antifungal and antitumor activity. The results indicate that the biological activity increases on complexation.
The CuII complexes of the above ligands show greater inhibitory action towards the P388/s tumor cells at lower concentrations. 相似文献
8.
The first inorg/organic hybrid complex incorporating the macrocyclic oxamide, of formula [(NiL)2Cu2(μ-NSC)2(NSC)2] (1), (NiL, H2L = 2, 3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien), have been synthesized and structurally characterized. The crystals crystallize in the triclinic system, space group P-1, for (1) a = 8.319(3) Å, b = 10.434(4) Å, c = 14.166(5) Å, a = 107.030(5)°, β = 91.257(5)°, γ = 107.623(5)°. The complex involved both bridging N, S-ligand, and oxamide ligand, C–H?S interactions and NCS → Ni weak coordination interactions making the complex superamolecular. 相似文献
9.
Hideki Ohtsu Tomoya Suzuki Hajime Ohtsuka Ayumi Ishii Miki Hasegawa 《Monatshefte für Chemie / Chemical Monthly》2009,140(7):783-787
Abstract A EuIII cryptate complex constructed from a CuII cryptand with an L
tBu ligand, [EuIIICu2II(L
tBu)2(NO3)3(MeOH)], and the corresponding CaII and NaI cryptates, [CaIICu2II(L
tBu)2(NO3)2(MeOH)2] and [NaICu2II(L
tBu)2(Me2CO)](BPh4), have been synthesized and characterized in order to shed light on the essential role of CuII in the luminescence of a EuIII cryptate. The unprecedented role of a CuII cryptand makes it possible to produce lanthanide luminescence in a EuIII cryptate complex and is successfully elucidated by comparison with the corresponding CaII and NaI cryptates.
Graphical abstract
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
10.
Huaze Dong Xia Liu Juan Yang Zhaolian Chu Wei Huang Shaohua Gou 《Transition Metal Chemistry》2007,32(4):518-522
Reactions of sodium 4-pyridin-2-yl-pyrimidine-2-sulfonate (NaL) with CuII and MnII ions in water produced a zig-zag chain polymer, [CuL(NCS)]
n
(1), and a dinuclear complex, [Mn2L2Cl2(H2O)2] (2), respectively. It is observed that counteranions and hydrogen bonds play basic roles in the resulting structure in which
3D networks were formed through intermolecular hydrogen bonding. 相似文献
11.
The structures of paramagnetic complexes CuCl2?L with L = HetCH2Si(OCH2CH2)3N [Het = pyrrol-1-yl (1), indol-1-yl (2), carbazol-9-yl (3), imidazole-1-yl (4), 3,5-dimethylpyrazol-1-yl (5), 1,2,4-triazol-1-yl (6), benzimidazol-1-yl (7), and 1,2,3-benzotriazol-1-yl (8)] were studied by the ESR and quantum chemical methods in terms of the density functional theory (DFT) approximation. The difference in structures of complexes CuCl2?1—CuCl2?8 is mainly determined by the nature of the five-membered heterocycle. The ESR spectra at room temperature are typical of the mononuclear complexes of CuII of axial symmetry with various types of distortions. In complexes CuCl2?1—CuCl2?3, narrow symmetric signals of zero-valent copper are recorded. These signals remain in the spectra for at least six months, which can characterize them as efficient stabilizing matrices of nanoparticles. 相似文献
12.
Ilhem Kaabi Tahar Douadi Djahida Haffar Salah Chafaa Magali Allain Mustayeen A. Khan Gilles M. Bouet 《Transition Metal Chemistry》2007,32(5):666-673
The crystal structure of a new symmetrical pentadentate N2O3 Schiff base: di[4-(phenylimino)pentan-2-one] ether (H2L) is described. In the solid state, the ligand appears as a keto-imine tautomer, while in DMSO solution, the eneamine form
is observed. This ligand coordinates cobalt(II), nickel(II), copper(II) and cadmium(II). The structures of these new complexes
are described using infrared and electronic spectroscopy, 1H-n.m.r. and d.s.c. The cyclic voltammograms of the ligand and the complexes in DMF are discussed. 相似文献
13.
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
14.
E. K. Beloglazkina A. G. Majouga A. A. Moiseeva M. G. Tsepkov N. V. Zyk 《Russian Chemical Bulletin》2007,56(2):351-355
The reaction of 5-[2-(methylthio)ethyl]-3-phenyl-2-thioxoimidazolidin-4-one (LH) with salts MCl2· xH2O (M = Co, Ni, Cu; x = 2, 6) afforded the [M(L)Cl]n complexes of NiII, CoII, and CuII. The electrochemical behavior of the LH ligand and its complexes was studied using the cyclic voltammetry and rotating disk
electrode techniques. The structures of the synthesized compounds were determined by the data of UV—Vis and IR spectroscopy,
mass spectrometry, and electrochemical characteristics.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 339–343, February, 2007. 相似文献
15.
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
16.
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
17.
Guo-Zhang Huang Ze-Yu Ruan Jie-Yu Zheng Jie-Yi Wu Yan-Cong Chen Quan-Wen Li Muhammad Nadeem Akhtar Jun-Liang Liu Ming-Liang Tong 《中国科学:化学(英文版)》2018,61(11):1399-1404
Single-molecule magnets (SMMs) are regarded as promising candidates for ultrahigh-density storage, quantum information processing and molecular spintronics. It is a crucial challenge for chemists to modulate magnetic dynamics of SMMs. Here, we successfully synthesized two 3d-4f polynuclear compounds [Co2Dy(TTTTCl)2(MeOH)]NO3·3MeOH (1) and [Co2Dy(TTTTCl)2 (MeOH)][Co(HTTTTCl)](NO3)2·2.5MeOH·2H2O (2), where H3TTTTCl=2,2′,2′′-(((nitrilotris(ethane-2,1-diyl)) tris(azanediyl)) tris(methylene))tris-(4-chlorophenol). On applying the approach by co-crystallization of bulky diamagnetic moiety, the effective energy barrier enhances from 401 K (1) to 536 K (2), which are both among the highest d-f heterometallic SMMs. 相似文献
18.
A condensation of 2,5-diamino-1,3,4-thiadiazole with the products of the in situ reaction of 1,2-dicyano-4-(4-triphenylmethylphenoxy)benzene with sodium alkoxides in a mixture of butanol—methanol furnished a trisubstituted ABABAB-type macroheterocycle (hemihexaphyrazine). A 3 : 1 trinuclear complex was synthesized by the reaction of the macrocycle with copper(II) acetate. The compounds obtained were characterized by IR spectroscopy, UV-vis spectroscopy, mass spectrometry, as well as by elemental analysis. Radioprotective properties of the water-soluble form of the complex were studied 相似文献
19.
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
20.
J. Song J. Liu J. Shi J. W. Ji R. Wu J. F. Lu Q. Zhang 《Russian Journal of Coordination Chemistry》2017,43(10):685-692
Two polymeric frameworks, [Zn(Dpb)(Oba)] n (Ι) and [Cd(Dpb)(2,6-Pda)H2O] n · nH2O (II) (Dpb = 1,4-bis(pyridin-3-ylmethoxy)benzene, H2Oba = 4,4'-oxybis(benzoic acid), 2,6-H2Pda = 2,6-pyridyl-dicarboxylate), have been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction method (CIF files CCDC 1488269 (Ι), 1488270 (II)). Complex Ι is a 2D layer structure, which is constructed from 1D double chain. Complex II is a 1D chain. The luminescent properties of Ι, II have been investigated with fluorescent spectra in the solid state, I and II displayed a strong fluorescent emission at room temperature. 相似文献