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1.
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   

2.
The composition of complexes formed upon the extraction of UVI and ThIV nitrates with O-n-nonyl(N,N-dibutylcarbamoylmethyl) methyl phosphinate (L) from solutions of nitric acid without additional solvent was determined by 31P NMR spectroscopy. The structures of the complexes formed were studied by IR spectroscopy. Uranium(VI) is extracted from 3 and 5 M solutions of HNO3 as the [UO2(L)2(NO3)2] complex, while thorium(IV) is extracted from 5 M HNO3 as the [Th(L)3(NO3)3]+·NO 3 complex. In both cases, ligand L has bidentate coordination. Ligand L contacts with 3 and 5 M nitric acid to form adducts L·HNO3 and L· (HNO3)2, respectively. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2460–2464, November, 2005.  相似文献   

3.
The reaction of di-μ-chlorobis(1,5-cyclooctadiene)dirhodium with (4S, 5S)-2,2-dimethyl-4,5-bis(methylaminomethyl)-1,3-dioxolane (1) gave the complex [Rh(cod)(1)]Cl (cod is 1,5-cyclooctadiene). The composition of the complexes CoCl2 · L2 and [Rh(cod)(L2)]X (L2 = 1, (4S,5S)-2,2-dimethyl-4,5-bis(aminomethyl)-1,3-dioxolane, and (4S, 5S)-2,2-dimethyl-4,5-bis(dimethylaminomethyl)-1,3-dioxolane; X = Cl, TfO) was studied using IR and 1H NMR spectroscopy. In the RhI cyclooctadienediamine complexes, the diene molecule forms a stronger bond with the metal atom than that in the cyclooctadienediphosphine analogs. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2270–2274, October, 2005.  相似文献   

4.
The reactions of bis(hexafluoroacetylacetonato)copper(II) [Cu(hfac)2] with the nitronyl nitroxide biradicals bis[4-(4,4,5,5-tetramethyl-3-oxide-1-oxyl-4,5-dihydro-1H-imidazol-2-yl)pyrazol-1-yl]alkanes (L6, L10, and L12) produced the framework heterospin complex [Cu(hfac)2]2L6 and the layer-polymeric heterospin complexes [Cu(hfac)2]2L10 and {[Cu(hfac)2]2L12} [Cu(hfac)2(PriOH)2], respectively. In the solid state of these compounds, the stereochemical nonrigidity is manifested as a deformation of the polymethylene fragments-(CH2)n-. 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. 1732–1741, September, 2007.  相似文献   

5.
New dinuclear ruthenium manganese complexes of general composition (bpy)2Ru(L)MnClx(H2O)2 (L is 1,10-phenanthroline-5,6-dione, 3,3′-dicarboxy-2,2′-bipyridyl, or bis(pyrazolyl); x = 2 or 4) were synthesized by the reaction of (bpy)2Ru(L) with MnCl2 · 4H2O. These compounds and the starting mononuclear ruthenium complexes were studied by spectrophotometric and electrochemical methods in MeCN. The position of the charge-transfer band RuII → L in the spectra depends on the donor-acceptor characteristics of the ligand L. For the dinuclear complex under study, the formal potentials of reversible one-electron oxidation of RuII are in the range of 0.9–1.2 V (vs. the standard hydrogen electrode), whereas oxidation of MnII occurs at more positive (by 0.1–0.2 V) potentials. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2281–2285, October, 2005.  相似文献   

6.
Dinuclear copper(II) complexes with acyldihydrazones of 2-hydroxy-5-nitroacetophenone (H4L) of the composition Cu2(Py)xmEtOH were synthesized and characterized. In these complexes, the coordination polyhedra of the copper atoms are linked to each other by a polymethylene chain of different lengths, from one to five monomer units. The structure of the [Cu2L·4Mrf] complex (Mrf is morpholine) based on acyldihydrazone of malonic acid was established by X-ray diffraction. The copper(II) atoms in this complex are [4+1]-coordinated and are spaced by 6.94 Å. At room temperature, the signal in the ESR spectra of solutions of the complexes based on acyldihydrazones of malonic, succinic, glutaric, and adipic acids has a seven-line hyperfine structure with the constant of (35.3–38.8)·10−4 cm−1 (g = 2.109–2.112) due to exchange interactions between unpaired electrons and two equivalent copper nuclei. An increase in the length of the polymethylene chain to five monomer units hinders exchange interactions, and the ESR signal of the complex based on acyldihydrazone of pimelic acid has a four-line hyperfine structure with a Cu = 72.7·10−4 cm−1 typical of mononuclear copper(II) complexes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 229–234, February, 2007.  相似文献   

7.
Spacer-armed dinuclear copper(II) complexes with condensation products of isophthalic and terephthalic acid dihydrazides with salicylaldehyde and 2-hydroxyacetophenone were synthesized and studied by EPR and X-ray diffraction. The compositions and structures of most of the complexes were determined by elemental analysis, thermogravimetric analysis, and IR spectroscopy. The structure of the copper(II) complex with acyldihydrazone of salicylaldehyde and 1,3-benzenedicarboxylic acid (H4L) with the composition [Cu2L1·2morph·MeOH] (morph is morpholine) was established by X-ray diffraction. The CuII atoms are spaced by 10.29 Å and are structurally nonequivalent. One copper cation has a square-planar coordination formed by donor atoms (2 N + O) of the doubly deprotonated acylhydrazine fragment and the N atom of the morpholine molecule. The second copper atom is additionally coordinated by a methanol molecule through the oxygen atom, so that this copper atom is in a tetragonal-pyramidal coordination with the oxygen atom in the axial position. The EPR spectra of liquid solutions of the complexes based on 1,4-benzenedicarboxylic acid acyldihydrazones and 1,3-benzenedicarboxylic acid bis(salicylidene)hydrazone at room temperature show a four-line hyperfine structure with the constant a Cu = 54.4–67.0·10−4 cm−1 (g = 2.105–2.147), which is indicative of the independent behavior of the paramagnetic centers. The EPR spectrum of a solution of the complex based on isophthalic acid and 2-hydroxyacetophenone shows the seven-line hyperfine structure corresponding to two equivalent copper nuclei (g = 2.11, a Cu = 36.5·10−4 cm−1). Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1898–1905, October, 2007.  相似文献   

8.
Critical phenomena in ethylbenzene oxidation in an acetic acid solution at high cobalt(III) concentrations (from 0.01 to 0.2 mol L−1) were studied at 60–90 °C by the gasometric (O2 absorption), spectrophotometric (CoIII accumulation), and chemiluminescence (relative concentration of radical RO2 ·) methods. These phenomena are as follows: (1) increase in the oxidation rate above the theoretical limiting rate of radical autooxidation (k 3 2[RH]2/2k 6); (2) achievement of a maximum and a sharp decrease in the oxidation rate and concentration of radical RO2 · with the further increase in the CoII concentration (existence of critical concentrations). The oxidation rate increases due to the reaction RO2 · + CoII + H+ → → ROOH + CoIII, while the inhibition effect is caused by the decay of RO2 · radical involving two cobalt(II) atoms: RO2 · + 2 CoII → R′CO + CoIII + CoII (k(70 °C) ≈ 300 L2 mol−2 s−1). The detailed scheme (through the formation of the complex RO2 ·CoII) describing the conjugation of these reactions was proposed. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1823–1827, August, 2005.  相似文献   

9.
The inclusion compound of macrocyclic cavitand cucurbit[8]uril (CB[8]) with the nickel(II) complex containing the tetraazamacrocyclic ligand cyclam, {[Ni(cyclam)]@CB[8]}Cl2··16H2O (1), and the inclusion compounds of CB[8] with the copper(II) bis-ethylene-diamine complex, {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·{CB[8]}·42H2O (2a) and {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·17H2O (2b), were synthesized and characterized by X-ray diffraction analysis, IR and ESR spectroscopy, and electrospray mass spectrometry. Guest—host inclusion compounds can be directly synthesized starting from a metal complex and cucurbit[8]uril, as was exemplified by the preparation of compounds 2a and 2b.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2414–2419, November, 2004.  相似文献   

10.
A series of the M(L)Cl2 · nH2O and {M(L)}2(OAc)4 complexes (M = NiII, CoII, and CuII; L is 3- and 4-(2-pyridyl)-1,3-benzothiazole) were synthesized by the reaction of L with MX2 · nH2O (X = Cl, OAc) in ethanol. The molecular and crystal structures of the CuL2(OAc)4 binuclear complex (L is 4-(2-pyridyl)benzothiazole) were determined by X-ray diffraction analysis. The copper atoms have a distorted tetragonal bipyramidal environment and are coordinated to the nitrogen atom of the pyridine moiety of the ligand and to two oxygen atoms of the bridging acetate ligands. The Cu-Cu distance is 2.6129(9) Å. The electrochemical behavior of the synthesized ligands and complexes was studied using the cyclic voltammetry and rotating disk electrode techniques in DMF solutions (0.1 M Bu4NClO4). The primary reduction of all the complexes under study is directed to the metal.  相似文献   

11.
The reactions of 2-(2-pyridyl)benzothiazole (1) with MX2·nH2O salts (M = NiII, CoII, or CuII; X = Cl or ClO4; n = 0–2) in EtOH afforded the corresponding complexes. Depending on the nature of the counterion in the starting metal salt, the reactions give compounds of composition M(1)Cl2·nH2O or Cu(1)2(ClO4)2·H2O. The molecular and crystal structure of the CuII(1)2(ClO4)2·H2O complex was established by X-ray diffraction. The copper atom in this complex has a distorted tetragonal-pyramidal ligand environment and is coordinated by four nitrogen atoms of two ligand molecules and one water molecule. Electrochemical study of the ligand and the resulting complexes by cyclic voltammetry and at a rotating disk electrode demonstrated that ligand 1 stabilizes reduced forms of complexes containing Ni, Co, or Cu atoms in the oxidation state +1. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1738–1744, October, 2006.  相似文献   

12.
N,N’-Polymethylenebis(thiosalicylidene)iminate and macrocyclic dithiadiazadibenzocycloalkadiene complexes of nickel(II) were synthesized and their electrochemical and spectroscopic properties were studied. Dithiadiazadibenzocycloalkadiene complexes containing two DMSO molecules coordinated to Ni2+ and two outer-sphere ClO4 anions were synthesized by the reaction of the corresponding macrocyclic ligands with Ni(ClO4)2·6H2O. The structure of 3,6-dithia-10,14-diazadibenzo[a,g]cyclopentadeca-9,14-dienylnickel(II)[bis(dimethyl sulfoxide) bis-perchlorate] was established by X-ray diffraction. The UV-Vis spectroscopic data are consistent with octahedral structures of diiminobis(sulfide) complexes, a square-planar structure of the thiosalen complex, and distorted tetrahedral structures of other diiminodithiolate complexes. The reaction of S-tert-butylthiosalicylaldehyde with hydrazine hydrate afforded di(ortho-tert-butylthiobenzal)azine. The reaction of the latter with anhydrous NiCl2 produced a colored complex with the simplest molecular formula Ni(C16H12N2S2) in 15% yield. Semiempirical PM3(tm) calculations and the results of UV-Vis, ESR, and 1H NMR spectroscopy demonstrate that this complex has most probably a dimeric structure, in which two Ni centers adopt a nearly square-planar configuration. The complexes are clearly divided into two types according to their electrochemical behavior in DMF solutions. The type 1 is characterized by reversibility of the first reduction steps. The type 2 is characterized by irreversible two-electron reduction as the first step accompanied by deposition of Ni metal on the electrode surface. Rapid electrochemically initiated alkylation occurs in the presence of various alkylating agents (BunI, BunBr, (DmgH)2CoCH3) in a solution of complex 1 in DMF.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 169–183, January, 2005.  相似文献   

13.
Transition metal (NiII, CoII, and CuII) complexes with 1,2-bis[2-(3-pyridylmethylideneamino)phenylthio]ethane (1) and 1,2-bis[2-(4-pyridylmethylideneamino)phenylthio]ethane (2) were synthesized for the first time by slow diffusion of solutions of compounds 1 or 2 in CH2Cl2 into solutions of MX2 · nH2O (M = Ni, Co, or Cu; X = Cl or NO3; n = 2 or 6) in ethanol. The reactions with CoII and CuII chlorides afford complexes of composition M(L)Cl2 (L = 1 or 2). The reactions of compound 1 with NiII salts produce complexes with 1,2-bis(2-aminophenylthio)ethane. The molecular structure of dinitrato[1,2-bis(2-aminophenylthio)ethane]nickel(ii) was confirmed by X-ray diffraction. The ligands and the complexes were investigated by cyclic voltammetry and rotating disk electrode voltammetry. The initial reduction of the complexes proceeds at the metal atom. The oxidation of the chlorine-containing complexes proceeds at the coordinated chloride anion. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 350–355, February, 2008.  相似文献   

14.
An efficient procedure was developed for the synthesis of alkyltetrazolyl-substituted nitronyl nitroxides (L 1 and L 2). These compounds were used to prepare the first alkyltetrazolyl-substituted imino nitroxides (L 3 and L 4). The molecular structures of L 3 and L 4 were confirmed by X-ray diffraction. Investigation of the products prepared by the reaction of copper(II) bis(hexafluoroacetylacetonate), Cu(hfac)2, with nitroxides made it possible to divide ligands L 1L 4 into two groups. The reactions of spin-labeled tetrazoles L 1L 3 with Cu(hfac)2 afford the heterospin complexes Cu(hfac)2L2, whereas L 4 serves as a bidentate ligand in the Cu(hfac)2 L 4 complex. In the solid Cu(hfac)2L2 complexes, antiferromagnetic exchange interactions between the unpaired electrons of the nitroxide fragments of the adjacent molecules prevail, due to which μeff decreases with decreasing temperature, and the spins of nitroxides are completely compensated at 5–10 K. The Cu(hfac)2 L 4 complex displays strong intramolecular ferromagnetic coupling, due to which μeff at room temperature is close to 2.9 μB. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 64–70, January, 2006.  相似文献   

15.
Transition metal complexes (NiII, CoII, and CuII) with tetradentate N2S2-type ligands (L), which are reaction products of 2-thio-substituted benzaldehydes with aromatic amines (3-aminopyridine or 2-aminothiophenol), were synthesized for the first time. The complexes have the composition L·MX2 or L·2MX2 (X = Cl or ClO4). The electrochemical behavior of the ligands and complexes was studied by cyclic voltammetry and rotating disk electrode voltammetry. Depending on the structure of the complexes, the metal atom in the latter is initially reduced in a one-or two-electron process. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2115–2124, November, 2007.  相似文献   

16.
The mononuclear complexes (η3-terpy)M(Piv)2·MeCN (M = Fe ii (3) and Co ii (4), and Piv is the pivalate anion) were synthesized by the reactions of polymeric iron(ii) and cobalt(ii) pivalates with 2,2′:6′,2″-terpyridine (terpy). The oxidation of compound 3 affords the pentanuclear heterospin iron(ii,iii) complex (η3-terpy)Fe54-O)(μ3-OH)(μ-OH)2(μ-Piv)71-Piv)2 (5). All compounds were characterized by X-ray diffraction. 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. 1186–1190, June, 2008.  相似文献   

17.
Kinetics of hydrogen peroxide decomposition in the presence of the tetraaquapalladium(II) complex in an aqueous solution at 40–70 °C was studied. The reaction rate is the first order with respect to the concentration of both PdII and H2O2 and the negative first order with respect to perchloric acid. Using free radicals traps, the reaction mechanism was found to differ from the traditional free-radical mechanism known for d-metal aqua ions and proceeds without generation of hydroxyl radicals. The kinetic data obtained suggest a mechanism involving the formation of an intermediate palladium complex with oxygen. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1077–1082, May, 2005.  相似文献   

18.
The sorption of anions H2PO4 , HPO4 2−, PO4 3−, [Fe(CN)6]3−, and [Fe(CN)6]4− from aqueous solutions on the surface of FeIII and ZrIV oxyhydroxide hydrogels freshly precipitated at pH 4–13 was studied. The region of sorbate concentrations was from 0.00025 to 0.06 mol L−1. The plots of the anion uptakes vs. their equilibrium concentrations are represented by isotherms of the first type, which are well described by the Langmuir equation if the quantity of the amount adsorbed is expressed as mol-site g−1. The maximum uptakes and constants of the Langmuir equation were calculated. The phosphate anions occupy the same number of sorption sites on the sorbents precipitated at different pH. The average specific content of sorption sites for the ferro- and zirconogels in the metastability period is independent of the pH of their precipitation, being 3.1·10−3 and 3.2·10−3 mol-site g−1, respectively. The [Fe(CN)6]3− and [Fe(CN)6]4− anions are sorbed only on the positively charged sites of the hydrogels and occupy not more than 2·10 mol-site g−1 in the studied interval of pH of precipitation. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1736—1741, August, 2005.  相似文献   

19.
The oxidation of lower aliphatic alcohols C1–C4 with dioxygen to form the corresponding carbonyl compounds in the presence of the PdII tetraaqua complexes and FeII-FeIII aqua ions in an aqueous medium was studied at 40–80 °C. The introduction of an aromatic compound (acetophenone, benzonitrile, phenylacetonitrile, o-cyanotoluene, nitrobenzene) and FeII aqua ion instead of the FeIII aqua ion into the reaction system increases substantially the catalytic activity and the yield of the carbonyl compound. The key role of the Pd species in the intermediate oxidation state stabilized by the aromatic additive in the catalytic cycle of alcohol oxidation with dioxygen to the carbonyl compound was shown. An increase in the kinetic isotope effect with an increase in the temperature of methanol oxidation indicates a change in the rate-determining step of alcohol oxidation with dioxygen in the presence of PdII-FeII-FeIII and the aromatic compound. At temperatures below 60 °C, the catalytically active palladium species are mainly formed upon the reduction of the PdII tetraaqua complex with the FeII aqua ion, whereas at higher temperatures the reaction between the alcohol and PdII predominates. The mechanism and kinetic equation of the process were proposed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 842–848, May, 2007.  相似文献   

20.
Ionic mobility in the NaSbClF3 · H2O, KSbClF3, and NH4SbClF3 fluorochloride complexes was studied by 1H and 19F NMR spectroscopy in the temperature interval from 150 to 480 K. The types of ionic motions in the compounds were determined. Their physicochemical characteristics were compared with those of the earlier studied sodium, potassium, and ammonium tetrafluoroantimonates(iii). The replacement of one F atom by the Cl atom in MSbF4 (M = Na, K, NH4) changes both the structure of the Sb polyhedra forming the structure of the antimony(iii) fluorochloride complex and the character of ionic motions in the compounds. The ionic conductivity in the 324–436 K range was determined for NH4SbClF3: σ = 1.07 · 10−4 S cm−1 at T = 423 K. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1353–1357, July, 2008.  相似文献   

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