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181.
Irena S. Akhrem Dzul’etta V. Avetisyan Lyudmila Afanas’eva Sergei V. Vitt Pavel V. Petrovskii Alexander Orlinkov 《Tetrahedron letters》2008,49(8):1399-1404
Alkanes (or cycloalkanes) and CO in the presence of superelectrophilic systems CX4·2AlBr3 (X = Cl, Br) have been applied for the first time as equivalents of acylium salts in one-pot selective syntheses of amides from amines. 相似文献
182.
Determination of the heats of gasification of polymers using differential scanning calorimetry 总被引:1,自引:0,他引:1
The amount of heat that is required to gasify unit mass of material is one of the key properties that define its ignition resistance and fire response. Knowledge of this property is necessary to assess a material's fire hazard in a particular fire scenario. Nevertheless, even for the most common polymers the values of this property are not well established. Here we present a method for determining the heat of gasification using differential scanning calorimetry and apply this method to a set of ten common plastics and engineering polymers. 相似文献
183.
T. Yu. Orlova Yu. S. Nekrasov P. V. Petrovskii M. G. Ezernitskaya Z. A. Starikova O. L. Lependina 《Russian Chemical Bulletin》2008,57(1):63-67
The metallation of the η5-C5H5(CO)2Fe-η1,η5-C5H4Mn(CO)3 complex with BunLi (THF, ?78 °C) followed by the treatment of the lithium derivative with Ph2PCl afforded the η5-Ph2PC5H4(CO)2Fe-η1,η5-C5H4Mn(CO)3 complex. The reaction of the latter with η5-C5H5(CO)3WCl in the presence of Me3NO produced the trinuclear complex η5-C5H5Cl(CO)2W-η1,η5-(Ph2P)C5H4(CO)2Fe-η1,η5-C5H4Mn(CO)3. The structure of the latter complex was established by IR, UV, and 1H and 31P NMR spectroscopy and X-ray diffraction. The reaction of MeSiCl3 with three equivalents of LiC5H4(CO)2Fe-η1,η5-C5H4Mn(CO)2PPh3 gave the hexanuclear complex MeSi[C5H4(CO)2Fe-η1,η5-C5H4Mn(CO)2PPh3]3. 相似文献
184.
Lukas Spree Christin Schlesier Dr. Aram Kostanyan Dr. Rasmus Westerström Prof. Dr. Thomas Greber Prof. Dr. Bernd Büchner Dr. Stanislav M. Avdoshenko Dr. Alexey A. Popov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(11):2436-2449
The substitution of scandium in fullerene single-molecule magnets (SMMs) DySc2N@C80 and Dy2ScN@C80 by lutetium has been studied to explore the influence of the diamagnetic metal on the SMM performance of dysprosium nitride clusterfullerenes. The use of lutetium led to an improved SMM performance of DyLu2N@C80, which shows a higher blocking temperature of magnetization (TB=9.5 K), longer relaxation times, and broader hysteresis than DySc2N@C80 (TB=6.9 K). At the same time, Dy2LuN@C80 was found to have a similar blocking temperature of magnetization to Dy2ScN@C80 (TB=8 K), but substantially different interactions between the magnetic moments of the dysprosium ions in the Dy2MN clusters. Surprisingly, although the intramolecular dipolar interactions in Dy2LuN@C80 and Dy2ScN@C80 are of similar strength, the exchange interactions in Dy2LuN@C80 are close to zero. Analysis of the low-frequency molecular and lattice vibrations showed strong mixing of the lattice modes and endohedral cluster librations in k-space. This mixing simplifies the spin–lattice relaxation by conserving the momentum during the spin flip and helping to distribute the moment and energy further into the lattice. 相似文献
185.
Mitja Krnel Primož Koželj Stanislav Vrtnik Andreja Jelen Magdalena Wencka Peter Gille Janez Dolinšek 《无机化学与普通化学杂志》2020,646(14):1099-1104
We present the anisotropic electrical and thermal transport coefficients (electrical resistivity, magnetoresistance, thermoelectric power, thermal conductivity), the magnetic properties, the specific heat and the electronic density of states of a monocrystalline In3Ni2 intermetallic compound, representing a precious-metal-free (and noble-metal-free) intermetallic catalyst for the selective hydrogenation of α,β-unsaturated aldehydes. The investigated physical parameters were determined along three orthogonal crystal-symmetry directions of the trigonal structure, the twofold axis, the 3 axis and within the mirror plane. All the investigated tensorial and vectorial quantities show the same anisotropy, with the quantities being isotropic for the twofold direction and in the mirror plane, whereas there is small, though still significant anisotropy to the 3 direction. The In3Ni2 crystal conducts the electricity and heat somewhat less efficiently along the 3 direction than along the twofold direction and in the mirror plane, but the differences are not large, of about 20 %. In3Ni2 is a diamagnetic intermetallic compound, with a presumably simple Fermi surface and electrons as the majority charge carriers. 相似文献
186.
Dmitri O. Charkin Stanislav I. Bezzubov Oleg I. Siidra Artem S. Borisov Stepan N. Kalmykov 《无机化学与普通化学杂志》2020,646(11-12):540-543
Crystals of a new uranyl sulfate (C2N4H8S2)[UO2(SO4)2] · 0.3H2O ( 1 ) templated by a relatively rare bis-isothiouronium cation, were formed upon evaporation of aqueous solutions containing uranyl acetate, thiourea, and excess sulfuric acid. The new compound is orthorhombic, P212121, a = 6.928(2) Å, b = 13.398(3) Å, c = 15.225(3) Å, Z = 2. Its crystal structure is comprised of [UO2(SO4)2] moieties linked by hydrogen bonds formed between the template cations and terminal oxygen atoms of the sulfate tetrahedra. The C2N4H8S22+ template is most likely formed in situ during a redox reaction between uranyl cation and thiourea in a strongly acidic medium, with UO22+ partially reduced to U4+. 相似文献
187.
A. I. Kovalev Yu. I. Lyakhovetskli M. M. Teplyakov A. L. Rusanov P. V. Petrovskii S. O. Yakushin 《Russian Chemical Bulletin》1993,42(9):1529-1535
The chemical heterogeneity of polyphenylenes obtained by trimerization poiycycio-condensation of acetylaromatic compounds has been investigated by GLC-MS analysis of the products of trimerization cyclocondensation of acetophenone. The mechanism for the formation of side products of the reaction is discussed. The presence of dypnone fragments in the polyphenylene structure results in a decrease in the thermal stability of these polymers.Deceased March, 1993.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1595–1601, September, 1993. 相似文献
188.
L. V. Rybin S. V. Osintseva A. S. Batsanov Yu. T. Struchkov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1993,42(7):1228-1235
The thermal reactions of Ru3(CO)12 with RCOCH=CHPh (R=Me, p-MeC6H4) in hydrocarbon solvents lead to the formation of a series of complexes, several of which have been isolated as individual compounds by chromatography. The dinuclear complex Ru2(-H)(CO)6(-MeCOCH=CPh) and the tetranuclear complex Ru4(-H)(-CO)(CO)7(p-MeC
6H4 COCH=CPh)(-p-MeC6H4COCH=CPh)(4-p-MeC6H3COCH=CHPh) are characterized by an X-ray structural study. The structures of other reaction products are discussed on the basis of spectral data. The reactions are accompanied by reduction of the starting enones to the corresponding unsaturated ketones.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1285–1293, July, 1993. 相似文献
189.
G. D. Kolomnikova T. O. Krylova I. V. Chernoglazova P. V. Petrovskii Yu. G. Gololobov 《Russian Chemical Bulletin》1993,42(7):1188-1190
In the presence of trifluoroacetic acid, ethyl 2-cyanoacrylate readily reacts with nucleophilic reagents, such as 2-chloro-1,3,2-benzodioxaphosphole, (EtO)3P, (EtO)2PCl, Ph2PCl, Ph3P, and thiourea. In these reactions the acid proton enters position 2 of the cyanoacrylate, whereas the nucleophilic component enters position 3, in accordance with the electron density distribution in the acrylate. In the absence of trifluoroacetic acid the above reagents, except 2-chloro-1,3,2-benzodioxaphosphole, cause ethyl 2-cyanoacrylate polymerization. The interaction of ethyl 2-cyanoacrylate with 2-chloro-1,3,2-benzodioxaphosphole and trifluoroacetic acid is the first example of a 2-cyanoacrylate taking part in the acid-initiated electrophilic conjugate addition of a weak nucleophile.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1245–1247, July, 1993. 相似文献
190.
S. A. Kuklin F. M. Dolgushin P. V. Petrovskii A. A. Koridze 《Russian Chemical Bulletin》2006,55(11):1950-1955
First ruthenocene-based palladium complexes PdCl[{2,5-(But
2PCH2)2C5H2} Ru(Cp′)] (Cp′ = C5H5 (4) or C5Me5 (5)) were synthesized. Comparative single-crystal X-ray diffraction study of complexes 4 and 5 showed that the deviations of the cyclopentadienyl rings in these complexes from being parallel are 2.6 and 10.1°, respectively.
In addition, the shift of the palladium atom relative to the plane of the metallated cyclopentadienyl ligand is 0.007 Å for
4 and 0.336 Å for 5. These differences in the structures of complexes 4 and 5 are due to close contacts between the pseudoequatorial tert-butyl groups at the phosphorus atoms and the unmetallated cyclopentadienyl ring.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1879–1884, November, 2006. 相似文献