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1.
Coropceanu E. Rudic V. Cepoi L. Rudi L. Lozan V. Chiriac T. Miscu V. Bulhac I. Kravtsov V. Bourosh P. 《Russian Journal of Coordination Chemistry》2019,45(3):200-207
Russian Journal of Coordination Chemistry - New fluorine-containing cobalt(III) dioximates [Co(DmgH)2(Thio)2]2F[PF6] (I) and [Co(DmgH)2(Sam)2]2[TiF6] · 4H2O (II) (DmgH = dimethylglyoxime... 相似文献
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Lozan V Buchholz A Plass W Kersting B 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(26):7305-7316
A series of novel tri- and pentanuclear complexes composed of dinuclear LM(2) units (M=Co, Ni, Zn; L=24-membered macrocyclic hexaazadithiophenolate ligand) and ferrocenecarboxylate ([CpFeC(5)H(4)CO(2)](-)) or 1,1'-ferrocenedicarboxylate ([Fe(C(5)H(4)CO(2))(2)](2-)) groups is reported. The complexes [LM(II) (2)(O(2)CC(5)H(4)FeCp)](+) (M=Co (6), Ni (7), Zn (8)) and [(LM(II) (2))(2)(O(2)CC(5)H(4))(2)Fe](2+) (M=Co (9), Ni (10)) have been prepared by substitution reactions from labile [LM(II) (2)L'](+) precursors (L'=Cl, OAc) and the respective ferrocenecarboxylate anions in methanol. Mixed-valent [(LCo(II)Co(III))(2)(O(2)CC(5)H(4))(2)Fe](4+) (11) was prepared by oxidation of 9 with bromine. Complexes 7[BPh(4)], 8[BPh(4)], 9[BPh(4)](2), 10[BPh(4)](2), and 11[ClO(4)](4) have been characterized by X-ray crystallography; showing that the ferrocenyl carboxylates act as bidentate (7, 8) or bis-bidentate (9-11) bridging ligands towards one or two bioctahedral LM(2) subunits, respectively. The structures are retained in solution as indicated by NMR spectroscopic studies on the diamagnetic Zn(2)Fe complex 8[ClO(4)]. Electrochemical studies reveal significant anodic potential shifts for the oxidation potential of the ferrocenyl moieties upon complexation and the magnitude of the potential shift appears to correlate with the charge of the LM(2) subunits. This is qualitatively explained in terms of destabilizing electrostatic (Coulomb) interactions between the M(2+) ions of the LM(2) unit and the proximate ferrocenium fragment. An analysis of the temperature-dependent magnetic susceptibility data for 10[BPh(4)](2) shows the presence of weak ferromagnetic magnetic exchange interactions between the Ni(II) ions in the LNi(2) units. The exchange coupling across the ferrocenedicarboxylate bridge is negligible. 相似文献
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P. Bourosh O. Ciobanica V. Lozan I. Bulhac 《Russian Journal of Coordination Chemistry》2012,38(7):461-470
A number of novel complexes of cobalt(III) trans-dioximates containing pyrazinecarboxamide were obtained: [CoBr(DfgH)2(Pzca)] · 0.125H2O (I), [CoCl(NioxH)2(Pzca)] (II), [CoCl(DmgH)(NioxH)(Pzca)] · 0.5C2H5OH · 0.5H2O (III), and [CoCl(DmgH)2(Pzca)] (IV), where DmgH, DfgH, and NioxH are the monoanions of dimethylglyoxime, diphenylglyoxime, and cyclohexane-1,2-dione dioxime, respectively; Pzca is pyrazinecarboxamide. Complexes I?CIII were examined by X-ray diffraction. In these complexes, the Co(III) atom has an octahedral environment with the pseudomacrocyclic fragment (DioxH)2 in the equatorial plane (DioxH is the ??-dioxime residue). The latter is stabilized by hydrogen bonds O-H?O. In all the complexes, the organic ligand is monodentate and coordinated through one N atom of the heterocycle so that it is trans to the halide anion. 相似文献
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P. N. Bourosh O. A. Bologa V. Lozan O. Ciobanica I. Bulhac A. V. Vologzhanina Yu. A. Simonov 《Russian Journal of Coordination Chemistry》2010,36(3):204-212
A series of new coordination compounds of cobalt(III) trans-dioximates with pyrazine [CoCl(DH)2Pz] · H2O (I), [CoBr(DH)2Pz] · H2O (II), [Co(DH)2Pz2]NO3 · H2O (III), [Co(DH)2Pz2][BF4] (IV), [Co(MgH)2Pz2][BF4] (V), and [Co(NioxH)2Pz2][BF4] (VI), where DH, MgH, and NioxH are dimethylglyoxime, methylglyoxime, and 1,2-cyclohexanedionedioxime monoanions, respectively,
Pz is a pyrazine molecule were synthesized. The structures of compounds I, II, and VI were determined by X-ray diffraction. The Co(III) environment in these compounds is octahedral and the pseudomacrocyclic
(DioxH−)2 fragment occurs in the equatorial plane. This fragment is stabilized by O-H…O hydrogen bonds. The neutral Pz ligand is monodentate
in all three compounds. 相似文献
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Journaux Y Glaser T Steinfeld G Lozan V Kersting B 《Dalton transactions (Cambridge, England : 2003)》2006,(14):1738-1748
The ligating properties of the 24-membered macrocyclic dinucleating hexaazadithiophenolate ligand (L(Me))2- towards the transition metal ions Cr(II), Mn(II), Fe(II), Co(II), Ni(II) and Zn(II) have been examined. It is demonstrated that this ligand forms an isostructural series of bioctahedral [(L(Me))M(II)2(OAc)]+ complexes with Mn(II) (2), Fe(II) (3), Co(II) (4), Ni(II) (5) and Zn(II) (6). The reaction of (L(Me))2- with two equivalents of CrCl2 and NaOAc followed by air-oxidation produced the complex [(L(Me))Cr(III)H2(OAc)]2+ (1), which is the first example for a mononuclear complex of (L(Me))2-. Complexes 2-6 contain a central N3M(II)(mu-SR)2(mu-OAc)M(II)N3 core with an exogenous acetate bridge. The Cr(III) ion in is bonded to three N and two S atoms of (L(Me))2- and an O atom of a monodentate acetate coligand. In 2-6 there is a consistent decrease in the deviations of the bond angles from the ideal octahedral values such that the coordination polyhedra in the dinickel complex 5 are more regular than in the dimanganese compound 2. The temperature dependent magnetic susceptibility measurements reveal the magnetic exchange interactions in the [(L(Me))M(II)2(OAc)]+ cations to be relatively weak. Intramolecular antiferromagnetic exchange interactions are present in the Mn(II)2, Fe(II)2 and Co(II)2 complexes where J = -5.1, -10.6 and approximately -2.0 cm(-1) (H = -2JS1S2). In contrast, in the dinickel complex 5 a ferromagnetic exchange interaction is present with J = +6.4 cm(-1). An explanation for this difference is qualitatively discussed in terms of the bonding differences. 相似文献
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V. Kh. Kravtsov V. I. Lozan Yu. A. Simonov O. A. Bologa N. V. Gerbeleu T. I. Malinovskii 《Journal of Structural Chemistry》1994,35(3):358-363
Bis-condensation of 4-methyl-2,6-diformylphenol with dimethyl N′,N′-hydrazine diacetate gave product I. The structure of I
was determined by X-ray analysis. The conformations of the two side chains of dimethyl N′,N′-hydrazine diacetate are significantly
different. The position of one chain is fixed by the intramolecular H-bond of O−H.…N type. Due to its conformation, compound
I is partly ready for complex formation with d-metals.
Institute of Applied Physics, Academy of Sciences, Moldova Republic. Institute of Chemistry, Academy of Sciences, Moldova
Republic. Translated fromZhurnal Struktumoi Khimii, Vol. 35, No. 3, pp. 91–98, May–June, 1994.
Translated by L. Smolina 相似文献
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Bernd Berchtold Vasile Lozan Paul‐Gerhard Lassahn Christoph Janiak 《Journal of polymer science. Part A, Polymer chemistry》2002,40(21):3604-3614
Nickel(II) and palladium(II) complexes with α‐dioxime ligands dimethylglyoxime, diphenylglyoxime, and 1,2‐cyclohexanedionedioxime represent six new precatalysts for the polymerization of norbornene that can be activated with methylaluminoxane (MAO), the organo‐Lewis acid tris(pentafluorophenyl)borane [B(C6F5)3], and triethylaluminum (TEA) AlEt3. The palladium but not the nickel precatalysts could also be activated by B(C6F5)3 alone, whereas two of the three nickel precatalysts but none of the palladium systems are somewhat active with only TEA as a cocatalyst. It was possible to achieve very high polymerization activities up to 3.2 · 107 gpolymer/molmetal · h. With the system B(C6F5)3/AlEt3, the activation process can be formulated as the following two‐step reaction: (1) B(C6F5)3 and TEA lead to an aryl/alkyl group exchange and result in the formation of Al(C6F5)nEt3?n and B(C6F5)3?nEtn; and (2) Al(C6F5)nEt3?n will then react with the precatalysts to form the active species for the polymerization of norbornene. Variation of the B:Al ratio shows that Al(C6F5)Et2 is sufficient for high activation. Gel permeation chromatography indicated that it was possible to control the molar mass of poly(norbornene)s by TEA or 1‐dodecene as chain‐transfer agents; the molar mass can be varied in the number‐average molecular weight range from 2 · 103 to 9 · 105 g · mol?1. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3604–3614, 2002 相似文献
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V. Ch. Kravtsov Yu. A. Simonov J. Lipkowski O. A. Bologa N. V. Gérbéléu V. I. Lozan 《Crystallography Reports》2002,47(1):80-85
The crystal structures of dimethyl 4-phenylthiosemicarbazidediacetate C13H17N3O4S (I) and its adduct [C8H12O8Rh2 (C13H17N3O4S)2] (II) with rhodium(II) acetate are determined by X-ray diffraction analysis. The unit cell parameters of crystals I are as follows: a = 8.066(6) Å, b = 15.812(6) Å, c = 24.977(8) Å, β = 94.88(3)°, space group P21/n, and Z = 8. The unit cell parameters of crystals II are a = 8.513(1) Å, b = 16.055(1) Å, c = 16.071(3) Å, β = 104.99(1)°, space group P21/c, and Z = 2. In structure I, two crystallographically independent molecules considerably differ from each other in the mutual orientation of the structural fragments containing the ester groups. In the centrosymmetric dimeric complex II, the organic molecule I acts as a monodentate thio ligand and adopts only one conformation. 相似文献
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