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991.
992.
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   
993.
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   
994.
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   
995.
996.
We propose a new approach to obtaining composites of the intercalation type based on polyaniline and V2O5. We have determined the characteristics of these composites using x-ray diffraction, IR spectroscopy, and EPR. We show that the compounds obtained exhibit stable redox properties in aqueous and aprotic electrolytes.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 31, No. 6, pp. 361–364, November–December, 1995.We would like to express our thanks to V. G. II'in for help in carrying out the x-ray phase investigations. This work was made possible with the partial support of the International Science Foundation (grant N U6B000).  相似文献   
997.
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   
998.
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   
999.
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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