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201.
3,4-Bis(hydroxymethyl)furan was electrolytically methoxylated during intense cooling. 4,5-Bis(hydroxymethyl)pyridazine was obtained by reaction of the methoxylation product — 2,5-dimethoxy-3,4-bis (hydroxymethyl)-2,5-dihydrofuran — with hydrazine hydrate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1306–1307, October, 1970.  相似文献   
202.
Summary For the primary alkyl halides (R=from C2H5 to n-C9H19; halogen=C1, Br, and I) and the simplest aryl halides (R=C6H5 and p-CH3C6H4) it was shown that the organomagnesium synthesis in absence of catalysts for the Grignard reaction can be applied with success to the preparation of heteroorganic compounds of elements of Groups II–IV (mercury, boron, aluminum, silicon, germanium, tin, phosphorus, arsenic, antimony).  相似文献   
203.
A series of 7-carboxy-3-R-1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes was synthesized by reduction of 3,5-dinitrobenzoic acid with sodium borohydride followed by Mannich reaction with formaldehyde and primary amines. The mechanism of decomposition under electron impact of the 3-azabicyclo[3.3.1]nonane was established. Enthalpies of formation of compounds synthesized were calculated by semiempirical PM3 method.  相似文献   
204.
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   
205.
An investigation was carried out of the spectral-luminescent and acid-base properties at the stage of formation of the hydrogen bond and during the protonation of compounds with annelated aromatic and heterocyclic rings, obtained by introduction of bridging groups -CH=CH- (I), -CH=N- (II) and -CO-N(CH3)-(III) in the 4- and 2-positions of the molecules of 4-substituted derivatives of 2,5-diphenyloxazole. The nature of the reaction center was estabished, and an analysis was carried out of its sensitivity to the electronic influence of the substituents, and the reasons for the observed differences in the properties of compounds of various reaction series are discussed. A comparative analysis of the fluorescent properties of the neutral and protonated forms of the oxazole derivatives studied was made and the conclusion that the generation is possible of laser emission by the protonated forms of compounds of the reaction series (I) was confirmed.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, No. 4, pp. 343–349, July–August, 1992.  相似文献   
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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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