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991.
The reaction of the complex Re2(CO)4(NO)2Cl4 (1) with NaSCMe3 (2) (in THF or MeCN, 65–80°C, 24 h) was studied at different ratios of the reagents (from 1∶2 to 1∶6). At the reagent ratio
of 1∶2, the binuclear complex Re2(CO)4(NO)2Cl2(μ-SCMe3)2 (3) was obtained as a mixture ofsyn andanti isomers (3a and3b, respectively) containing Re2S2 fragments with different structures (the butterfly-like structure in3a and the planar fragment in3b). When the initials were taken in ratios from 1∶4 to 1∶6, two compounds were isolated: the binuclear complex Re2(CO)4(NO)2(μ-SCMe3)2(μ-S)4 (cocrystallized as a mixture ofsyn andanti isomers,4a and4b, respectively) and the triangular cluster Re3(CO)3(NO)3(μ-SCMe3((μ3-S)(μ3-Cl) (5). Apparently, complex4 is formed in the course of isolation as a result of elimination of SR2 from the unstable tetrathiolate dimer Re2(CO)4(NO)2(SCMe3)2(μ-SCMe3)2 (6). Cluster5 is the product of the reaction between compounds3 and4. Products of interaction of compound6 with silica gel upon column chromatography of the reaction mixture were studied. Four complexes containing hydroxy and oxo
bridging groups, (CO)2(NO)Re(μ-SCMe3)2(μ-OH)Re(SCMe3)(CO)(NO) (7), (CO)3(NO)3RE3(μ-SCMe3)3(μ3-SCME3)(μ3-O) (8), [(CO)2(NO)2Re2(SCMe3)2(μ-SCMe3)2(μ-OH)][Na(THF)(Et2O)] (9), and [(CO)2(NO)2Re2(SCMe3)2(μ-SCMe3)2(μ-OH)]2−[Na(H2O)6][H5O2] (10), were isolated. The structures of complexes3, 4, 5, 7, 8, 9, and10 were established by X-ray diffraction study.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1030–1044, May, 1998. 相似文献
992.
Artyukhin AB Shestakov A Harper J Bakajin O Stroeve P Noy A 《Journal of the American Chemical Society》2005,127(20):7538-7542
Use of biological machines and environments in novel bioinorganic nanostructures is critical for development of new types of biosensors, bio-NEMS devices, and functional materials. Lipid bilayers that mimic a cell membrane have already played an important role in such applications. We present supported lipid bilayers that spontaneously assemble in a continuous nanoshell around a template of a carbon nanotube wrapped with hydrophilic polymer cushion layers. We demonstrate that such 1-D lipid membranes are fluid and can heal defects, even over repeated damage-recovery cycles. A simple diffusion model can describe mobility of lipid molecules in these 1-D nanoshells. These structures could lead to the development of new classes of biosensors and bioelectronic devices. 相似文献
993.
A. I. Sidorov E. M. Sulman L. M. Bronshtein T. V. Ankudinova Yu. E. Avtushenko E. Sh. Mirzoyeva E. Yu. Baukova P. M. Valetskii 《Reaction Kinetics and Catalysis Letters》1991,44(1):57-62
Kinetic studies of pseudoionon hydrogenaiton on rhodium-containing catalysts have been carried out. The suggested kinetic model agrees well with the experimental data. The inverse problem was solved using an explicit integral method on an IBM PC computer.
. . IBM PC.相似文献
994.
Aleksandrov G. G. Fomina I. G. Sidorov A. A. Mikhailova T. B. Zhilov V. I. Ikorskii V. N. Novotortsev V. M. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2004,53(6):1200-1207
The reaction of the dinuclear complex Co2(bpy)2(OOCBut)4 with the tetranuclear complex Ni4(3-OH)2(OOCBut)6(EtOH)6 afforded the trinuclear heterometallic complex M3(bpy)2(3-OH)(-OOCBut)4(OOCBut) (6) (M = Ni, Co; Ni : Co = 1.2 : 1) in which two metal atoms are in an octahedral environment and one metal atom is in a tetrahedral environment. The reaction of 2,2"-bipyridine with Co4(3-OH)2(OOCBut)6(HOEt)6 (reagent ratio was 2 : 1) or the reaction of bpy with Co8(4-O)2(
n
-OOCBut)12 (reagent ratio was 4 : 1) produced a homometallic analog of 6, viz., the trinuclear cluster Co3(bpy)2(3-OH)(-OOCBut)4(OOCBut) (8). The reaction of 1,10-phenanthroline (phen) with the [Co(OH)
n
(OOCBut)2–n
]
x
polymer gave the analogous trinuclear cluster (phen)2Co3(3-OH)(2-OOCBut)4(1-OOCBut). Compounds 6 and 8 exhibit antiferromagnetic spin-spin exchange interactions. 相似文献
995.
A. A. Sidorov M. E. Nikiforova E. V. Pakhmutova G. G. Aleksandrov V. N. Ikorskii V. M. Novotortsev I. L. Eremenko I. I. Moiseeva 《Russian Chemical Bulletin》2006,55(11):1920-1932
The reaction of 2-hydroxy-6-methylpyridine with Co(NO3)2·6H2O or Co(F3CSO3)2·6H2O in the absence of a deprotonating agent produces the mononuclear complexes Co(HL)4(NO3)2 or Co(HL)4(F3CSO3)2 (HL is 6-methyl-2-pyridone), respectively. In the presence of triethylamine, the reaction affords the trinuclear complex
Co3(HL)2(L)4(NO3)2 or the heptanuclear dicationic complex [Co7L12]·(F3CSO3)2·4MeCN in the case of cobalt nitrate or cobalt trifluoromethanesulfonate, respectively. When HL is deficient, the replacement
of the trimethylacetate anions in polymeric cobalt pivalate [Co(OH)n(OOCCMe3)2−n
]x gives rise to the hexanuclear complex Co6(μ3-OH)2(η2,μ3-L)2(μ-OOCCMe3)8(HOOCCMe3)4, whereas the HLCo6(μ3-OH)(η2,μ3-L)3(η2,μ-L) (μ3-L)(μ3-OOCCMe3)(μ-OOCCMe3)4(η2-OOCCMe3) complex is generated when HL is present in excess. The structures of the reaction products were established by X-ray diffraction.
Dedicated to Academician O. M. Nefedov on the occasion of his 75th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1851–1862, November, 2006. 相似文献
996.
Chernyadyev A. Yu. Ustynyuk Yu. A. Aleksandrov G. G. Sidorov A. A. Novotortsev V. M. Ikorskii V. N. Nefedov S. E. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2002,51(8):1575-1580
The reactions of pyrrole-2,5-dicarbaldehyde (1) with 2-aminodiphenylamine (3) taken in a ratio of 1 : 2 in the presence of polinuclear nickel(ii) and cobalt(ii) trimethylacetate complexes were studied in MeCN. The reaction with Ni9(HOOCCMe3)4(4-OH)3(3-OH)3(OOCCMe3)12 (2) afforded the mononuclear complex Ni(OOCCMe3)2[(PhHN)C6H4NHCHC4H2NCHNC6H4(NHPh)] (4) with a new ligand, which is the product of condensation of one molecule 1 with two molecules 3 and contains two NHPh groups. By contrast, the reaction with the polymeric complex [Co(OH)
n
(OOCCMe3)2–n
]
x
(5, n = 0.05—0.1) gave rise to the tetranuclear complex Co4(4-O)(-OOCCMe3)4L2 (6), where L is, apparently, the product of further oxidation of Schiff"s base to the benzimidazole derivative. The structures of compounds 4 and 6 were established by X-ray diffraction analysis. 相似文献
997.
I.?L.?EremenkoEmail author M.?A.?Kiskin I.?G.?Fomina A.?A.?Sidorov G.?G.?Aleksandrov V.?N.?Ikorskii Yu.?G.?Shvedenkov Yu.?V.?Rakitin V.?M.?Novotortsev 《Journal of Cluster Science》2005,16(3):331-351
Antiferromagnetic Mn(II) polymers of general formula {[L2Mn(μ-OOCCMe3)2][Mn2(μ-OOCCMe3)4]}n (L = 1,2-phenylenediamine (3) and 4,5-dimethyl-1,2-phenylenediamine (4)) were synthesized from [Mn(μ-OOCCMe3)2(HOEt)]
n
(1) polymer and arenediamines in MeCN solution. The tetranuclear cluster Fe4(μ3-OH)2(μ-OOCCMe3)4(η2-OOCCMe3)2(EtOH)6 (5) was prepared by reacting FeSO4·7H2O with KOOCCMe3 in EtOH and was used as starting pivalate iron(II) agent in further reactions. The thermolysis of 5 in MeCN was shown to result in a ferromagnetic polymer [Fe(μ-OOCCMe3)2]
n
(6) containing tetrahedral iron(II) atoms. Cluster 5 was found to react with o-phenylenediamine giving rise to ferrimagnetic polymer [Fe(μ-OOCCMe3)2(HOEt)]n (7). The reaction 7 with 2,6-diaminopyridine in MeCN results in binuclear antiferromagnetic complex (2,6-(NH2)2C5H3N)2Fe2(μ-OOCCMe3)4· 4MeCN (8). However the reaction of 4,5-dimethyl-1,2-phenylenediamine with polymer 7 yields a polymer {[L2Fe(μ-OOCCMe3)2][Fe2 (μ-OOCCMe3)4]}
n
(9), which is an analogue of the manganese polymer 4. All newly synthesized compounds were characterized by the by X-ray diffraction studies and magnetic measurement.
Dedicated to Professor Ilya I. Moiseev in recognition of his outstanding contribution to cluster chemistry 相似文献
998.
It is shown that the difficulties in obtaining the correlation functions of rotational 2R(t) and vibrational v(t) relaxation associated with the construction of the profile of isotropic scattering from the observed profiles I
VV
*
() and I
VH
*
() with subsequent Fourier transformation of the constructed profile can be eliminated by a Fourier transformation of the profiles I
VV
*
() and I
VH
*
() directly with subsequent normalization of the obtained correlation functions G
VV
*
(t) and G
VH
*
(t) at the time t=0. The correlation functions 2R(t) and v(t) are obtained from the profiles of the Stokes and anti-Stokes Raman scattering lines. It is established that for lines with comparatively high polarization (p < 0.20) the correlation function 2R(t) and v(t) obtained by processing the observed profiles of the Stokes and anti-Stokes lines are almost identical.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 8–13, September, 1980. 相似文献
999.
Bronstein LM Sidorov SN Zhirov V Zhirov D Kabachii YA Kochev SY Valetsky PM Stein B Kiseleva OI Polyakov SN Shtykova EV Nikulina EV Svergun DI Khokhlov AR 《The journal of physical chemistry. B》2005,109(40):18786-18798
The paper provides new insights into the structure of Pt-containing diblock and triblock copolymers based on poly(ethylene oxide) (PEO) and poly(4-vinylpyridine) (P4VP), using a combination of atomic force microscopy (AFM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and anomalous small-angle X-ray scattering (ASAXS). Parallel studies using methods contributing supplemental structural information allowed us to comprehensively characterize sophisticated polymer systems during metalation and to exclude possible ambiguity of the data interpretation of each of the methods. AFM and TEM make available the determination of sizes of the micelles and of the Pt-containing micelle cores, respectively, while a combination of XRD, TEM, and ASAXS reveals Pt-nanoparticle size distributions and locations along with the structural information about the polymer matrix. In addition, for the first time, ASAXS revealed the organization of Pt-nanoparticle-filled diblock and triblock copolymers in the bulk. The nanoparticle characteristics are mainly determined by the type of block copolymer system in which they are found: larger particles (2.0-3.0 nm) are formed in triblock copolymer micelles, while smaller ones (1.5-2.5 nm) are found in diblock copolymer micelles. This can be explained by facilitated intermicellar exchange in triblock copolymer systems. For both systems, Pt nanoparticles have narrow particle size distributions as a result of a strong interaction between the nanoparticle surface and the P4VP units inside the micelle cores. The pH of the medium mainly influences the particle location rather than the particle size. A structural model of Pt-nanoparticle clustering in the diblock PEO-b-P4VP and triblock P4VP-b-PEO-b-P4VP copolymers in the bulk was constructed ab initio from the ASAXS data. This model reveals that nearly spherical micellar cores of about 10 nm in diameter (filled with Pt nanoparticles) aggregate forming slightly oblate hollow bodies with an outer diameter of about 40 nm. 相似文献
1000.
A magnesium complex of meso-formyletioporphyrin I (FEP) was obtained by reaction of FEP with methylmagnesium iodide. The electronic and IR spectra of FEP and its complexes with copper, zinc, nickel, cobalt, and magnesium in solutions and crystalline films were investigated. It is shown that the changes in the electronic spectra as the temperature of the solutions is lowered are due to association of the molecules of the metal complexes (M-FEP) of the metal-formyl type. Association of the molecules in solid films is accomplished through - electron interaction of the porphyrin rings. The Mg-FEP complex, the molecules of which associate through a metal-formyl interaction both in solution and in films, constitutes an exception to this.For communication V, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 919–925, July, 1977. 相似文献