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991.
Carbamoylformhydroxymoyl chlorides were synthesized by the reactions of carbamoylformamide oximes with sodium nitrite in the presence of hydrochloric acid, and their reactivities were examined.  相似文献   
992.
Orlov  I. S.  Moiseeva  A. A.  Butin  E. P.  Egorov  M. P. 《Russian Chemical Bulletin》2002,51(10):1961-1962
An unusual reaction of diaminogermylene and diaminostannylene with sterically hindered phenols which leads to the formation of stable phenoxyl radicals in high concentrations was found. The reaction mechanism was proposed. Amides [(Me3Si)2N]2E (E = Ge, Sn) were investigated electrochemically.  相似文献   
993.
Russian Chemical Bulletin - The monomer [Cr3O(OCOCH=CH2)6]OH was produced by reaction of acrylic acid with fresh chromium hydroxide. This monomer was investigated by a number of physicochemical...  相似文献   
994.
995.
A polarization variant of an intracavity laser spectrometer based on the competition of beams in an argon ion laser, radiating a number of narrow lines in the 275 to 529 nm spectral range, is proposed and described for the spectral analysis of liquid samples, having broad absorption bands, mainly biomolecules in solutions. By careful optimization of the operating conditions, a procedure has been established that results in a minimal measurable absorbance decreased up to 10(-5) units of optical density. The examined spectrometer provides a wide dynamic range of analysis. A determination of trace contents of amino acids in methanol were carried out.  相似文献   
996.
The molecular structures of the initial compounds and the products of photocyclization involving amino and azomethine groups in perchlorates ofN-amino (1) andN-azomethine (2) derivatives of 2,4,6-triphenylpyridinium cations were studied. Cations1 and2 have an essentially non-coplanar arrangement of the -Ph rings, and the product of photocyclization of2, cation3, is characterized by a flattened structure. It was found that the orientation of the lone electron pair of the N atom with respect to one of the planes of the -Ph rings in molecule1 is more favorable for monocyclization involving the amino group. The structure of molecule2 allows two routes of the photoreaction,viz., O N proton transfer and monocyclization with an -Ph ring. However, the structural features of molecule2 are more favorable for photocyclization.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 296–301, February, 1995.  相似文献   
997.
998.
999.
It is shown that it is possible to increase the yield of liquid hydrocarbons of the benzene fraction in the Mobil process by use of a catalyst modified by treatment with CO2 of the Zn form of the TsVK zeolite. It is established that on treatment with CO2 of the Zn-TzVK zeolite the concentration of strongly acidic -centers is increased. As a result of alkylation of C2-C4 olefins by methanol at these sites more of the high molecular C5-C8 aliphatic hydrocarbons are formed. Selectivity of conversion of methanol to liquid C5-C10 hydrocarbons of the benzene fraction is increased, but selectivity with respect to the light C2-C4 fractions is decreased.  相似文献   
1000.
The reaction of 2-chloro-5-methylbenzoquinone with -aminocrotonic ester derivatives was studied by PMR spectroscopy in CD3COOD. The spectra indicate the formation of intermediate hydroquinone and quinone derivatives, which subsequently transform into the corresponding indoles. It was shown that the indolization proceeds unequivocally at the 3-position of the initial benzoquinone, and the rate of formation of the indole derivatives decreases with increase in the size of the substituent at the nitrogen atom of the -aminocrotonic ester. The starting, intermediate compounds and the end products observed in the PMR spectra were identified by comparison with specially synthesized compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 324–328, March, 1990.  相似文献   
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