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951.
V. V. Zverev B. M. Musin V. M. Vakar' Z. G. Bazhanova V. B. Ivanov 《Journal of Structural Chemistry》1994,35(2):209-214
The electronic structure of some amino-N-sulfenyl chlorides and related compounds is studied by photoelectron spectroscopy
and ab initio calculations. Similar values of IP(n
S
) and IP(n
N
) and the total energy minimum indicate that in stable conformations the n
S
and n
N
orbitals are orthogonal. These conformers are characterized by an effective nN-σ
S-Cl
*
interaction. The relationship between the intramolecular shift of charge and ionization potential values and the spatial
structure of amino-N-sulfenyl chlorides is analyzed.
A. E. Arbuzov Institute of Organic and Physical Chemistry, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 2, pp. 69–73, March–April, 1994.
Translated by L. Smolina 相似文献
952.
S. D. Fazylov A. M. Gazaliev M. Zh. Zhurinov R. Z. Kasenov A. B. Tateeva M. Z. Kokzhalova 《Chemistry of Natural Compounds》1994,30(3):371-372
The results are given of the synthesis and a comparative study of the toxicities of some phosphorylated derivatives of the
alkaloids l-ephedrine and d-pseudoephedrine. It has been shown that the introduction of phosphorus- and sulfur-containing
fragments considerably lowers the toxicity of the alkaloids.
Institute of Organic Synthesis and Coal Chemistry, National Academy of Sciences of the Republic of Kazakhstan, Karaganda.
Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 406–408, May–June, 1994. 相似文献
953.
O. G. Yarosh Z. G. Ivanova T. D. Burnashova M. G. Voronkov 《Russian Chemical Bulletin》1984,33(11):2394-2396
Conclusions The reaction of magnesium bromide derivatives of di- and triethynylsilanes with dimethylethynylfluorosilane gave 1,2-disubstituted silylacetylenes containing ethynyl and vinyl groups at the silicon atoms.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2614–2616, November, 1984. 相似文献
954.
Z. G. Aliev L. O. Atovmyan A. M. Sipyagin V. G. Kartsev O. V. Dobrokhotova 《Chemistry of Heterocyclic Compounds》1987,23(4):390-395
A one-step synthesis of azetidin-3-ones by intramolecular cyclization of 1-diazo-3-arenesulfamoylalkan-2-ones was developed. The yield of cyclic product increases to 70% in the presence of an alkyl or benzyl substituent in the hydrocarbon chain of the diazoketone. The structure of N-tosyl-2-ethylazetidin-3-one was studied by x-ray diffraction analysis and it was shown that the four-membered ring has 15 inflection.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 468–473, April, 1987. 相似文献
955.
A model describing the wetting of structural elements in polycrystals such as grain boundaries (faces), triple lines (edges), and quaternary nodes (vertices) is proposed. It is assumed that the only driving force during wetting is the tendency of a system to the energy minimization due to the substitution of low-energy liquid–solid interfaces for high-energy grain boundaries. In this case, the anisotropy of grain boundary energy caused by the differences in misorientation of adjacent grains is taken into account, whereas the liquid–solid interface energy is assumed to be independent of the orientation. The well-known condition of grain boundary wetting (the Gibbs–Smith condition) is extended to the triple lines and quaternary nodes by introducing parameters determined as characteristic free energy of these elements. 相似文献
956.
Sequential leaching methods have been used for the speciation of Be, Ni, and V in five soil samples from Csepel Island on the Danube river located near an oil-fired power plant. The concentrations of the elements of the extracts were determined by inductively coupled plasma mass spectrometry. The total efficiency (the sum of the extracted metals divided by metal fraction which is soluble in aqua regia) of the five-step method was always higher. The difference for Ni was considerable, because of the high abundance of Ni found in the moderately reducible fraction, which is absent from the three-step method. The sum of the mobile species (exchangeable, carbonatic, and easily reducible) determined by both methods, were in reasonable agreement; this was not so for the individual fractions. There were greater differences between the non-mobile fractions (moderately reducible and oxidizable), because of the presence or absence of the moderately reducible fraction. For both methods there was good correlation between the oxidizable fraction and the organic matter content of the soils. 相似文献
957.
Jalal A.?Zahra Bassam Abu?Thaher Mustafa M.?El-Abadelah Hans-Hartwig?OttoEmail author 《Monatshefte für Chemie / Chemical Monthly》2005,136(4):567-570
Summary. Nitrilimines prepared from N-arylhydrazono chlorides reacted with 2-mercaptonicotinic acid yielding the corresponding addition products, 2-[(2-oxo-1-arylhydrazonopropan-1-yl)mercapto] nicotinic acids, which were treated with 1,1-carbonyldiimidazole in THF affording by cyclocondensation the corresponding hitherto unknown 2-arylhydrazono-3-oxothieno[2,3-b]pyridines. 相似文献
958.
Ferreira KQ Cardoso LN Nikolaou S da Rocha ZN da Silva RS Tfouni E 《Inorganic chemistry》2005,44(16):5544-5546
The synthesis of cis-[Ru(II)(cyclen)(L)(x)](n+) (cyclen = 1,4,7,10-tetraazacyclododecane and L = 2,2'-bipyridine (bpy), phenanthroline (phen) or 4-cyanopyridinium (4-NCpyH(+))) is reported. The freshly prepared complexes are stable in aprotic solvents and cyclen undergoes oxidative dehydrogenation reaction at high pH. These compounds also present solvent dependent conformational isomerization. 相似文献
959.
A study of the tautomerism of the N-alkyl-3-methoxycarbonyl-4-piperidinones and their hydrochlorides
B. A. Arbuzov O. A. Erastov A. B. Remizov L. Z. Nikonova 《Chemistry of Heterocyclic Compounds》1969,5(1):62-65
The positions of the equilibria of N-alkyl-3-methoxycarbonyl-4-piperidinones in the liquid state, in water, in alcohols, and in CCl4 have been determined by IR and UV spectroscopy. It has been shown that Meyer's equation is not satisfied for them. This is due to the high steric requirements of the solvating electron pair of the nitrogen atom. On the basis of the fact that on passing from the methyl ester of cyclohexan-1-one-2-carboxylic acid to the N-alkyl-3-methoxycarbonyl-4-piperidones the position of the equilibrium in the liquid state and in CCl4 does not shift in the direction of the enol it is deduced that the spatial requirements of the free electron pair of the nitrogen atom do not appreciably exceed the steric requirements of the hydrogen atom. The IR and UV spectra of the chlorides of the N-alkyl-3-methoxycarbonyl-4-piperidinones in the solid state and in water and in alcohols are given. 相似文献
960.
Zusammenfassung Es wurde die thermische Zersetzung dercis-undtrans-Isomeren des [PtAox
2Cl2] sowie des [PtAox
3Cl]Cl mit Hilfe derTG-undTD-Kurven im Falle des reinen Komplexes sowie im Falle einer Mischung mit Al2O3 (1:3) geklärt. Dietrans-Form ist stabiler als diecis-Form, die Zersetzung wird durch Al2O3 nicht beeinflu\t. [PtAox
3Cl]Cl wird infolge der Erhitzung in die stabileretrans-Form [PtAox
2Cl2] umgewandelt und verhält sich auch weiterhin wie diese.
Mit 4 Abbildung 相似文献
A contribution to the study of the compounds of Pt(II) with acetoxime
The thermal decomposition ofcis- andtrans-[PtAox 2Cl2] and of [PtAox 3Cl]Cl was studied by means ofTGA andTDA on pure substances as well as on mixtures with Al2O3 (1:3). Thetrans form is more stable then thecis form, the presence of Al2O3 has no influence on its decomposition. The [PtAox 3Cl]Cl is transformed by heating into the more stabletrans-isomer and its further behaviour is identical with that of thetrans isomer.
Mit 4 Abbildung 相似文献