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71.
The asymmetric synthesis of O-acetylated mandelonitrile derivative was accomplished from PhCHO, KCN, and Ac2O in a toluene--water system in the presence of transition metal complexes of Schiff"s bases as phase transfer catalysts.  相似文献   
72.
The action of ozone on aryl(methyl)-substituted 2- and 4-hydroxyamino- or -nitrosopyrimidines in chloroform gave 2- and 4-nitropyrimidines. The unambiguous character of the process depends on the molar ratio of the substrate and ozone; the side formation of azoxy-, chloro-, and hydroxypyrimidines is possible. 2-Nitro-sym-triazines were obtained by ozonization of substituted 2-hydroxyamino-sym-triazines.See [1, 2] for our preliminary communications.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 657–661, May, 1990.  相似文献   
73.
Consecutive treatment of methyl-substituted quinolinium and 2,6-diarylpyrilium perchlorates with sodium ethylate and equimolar amount of anhydrous cadmium(II) trifluoroacetate gives 2- and 4-methylenecadmium-containing salts of the above heterocyclic cations in 80-97% yields. The reactions of the cadmium-containing quinolinium and pyrilium salts with hydrochloric acid, acetic anhydride, mercuric trifluoroacetate, SnCl2, and nickel(II) trifluoroacetate, resulting in substitution of the CdOCOCF3 group by hydrogen, Ac, HgOCOCF3, SnCl, and NiOCOCF3, respectively, were studied.  相似文献   
74.
We develop a diagram theory for the periodic Anderson model assuming that the Coulomb repulsion of localized f electrons is the main parameter of the theory. The f electrons are strongly correlated and the c conduction electrons are uncorrelated. We determine the f-electron correlation function and the c-electron mass operator. We formulate the Dyson equation for c electrons and a Dyson-type equation for f electrons and their propagators. We define the skeleton diagrams for the correlation function and the thermodynamic functional. We establish the stationarity of the renormalized thermodynamic potential under variation of the mass operator. The obtained results are applicable to both the normal and the superconducting system states.  相似文献   
75.
Condensation of 3-substituted 3-azabicyclo[3.3.1]nonan-9-ones with hydroxylamine and hydrazine hydrate gave the corresponding oximes, hydrazones, and azines. Reductive amination of the title compounds in the presence of sodium triacetoxyhydridoborate led to the formation of 3-substituted 3-azabicyclo[3.3.1]nonan-9-amines which were converted into the corresponding dihydrochlorides by treatment with dry hydrogen chloride. Treatment of 3-tert-butoxycarbonyl derivatives with HCl under analogous conditions was accompanied by elimination of the tert-butoxycarbonyl group to produce 3-azabicyclo[3.3.1]nonan-9-amine dihydrochlorides.  相似文献   
76.
77.
Kinetics of the monomercuration by the active methyl groups of 2- and 4-methyl-containing salts of quinolinium, pyridinium, benzothiazolium, and pyrrilium with mercury(II) acetate and trifluoroacetate in a mixture of anhydrous ethanol and acetonitrile (3:1) at 50-70°C were studied by means of acid-base potentiometric titration. The apparent second-order rate constants of these reactions were estimated, and factors affecting their rate were considered. A mechanism of the reactions was offered.  相似文献   
78.
Treatment with mercury(II) trifluoroacetate of deprotonated (6-toluene)- and (6-diphenyl- methane)(5-cyclopentadienyl)iron(II) complexes gave mono-, di-, and trisubstituted [from (6-toluene)(5-cyclopentadienyl)iron(II) cation] mercury-containing salts. The reaction of mercury(II) trifluoroacetate with deprotonated (6-triphenylmethane)(5-cyclopentadienyl)iron(II) afforded only the corresponding sym- metric mercury derivative. The same product was obtained by direct mercuration with mercury(II) trifluoroacetate of (6-triphenylmethane)(5-cyclopentadienyl)iron(II) on heating the reactants in boiling unhydrous ethanol. Reactions of the resulting mercury-containing compounds with acids, symmetrizing bases, and acylating agents were studied.  相似文献   
79.
The reaction of mercury(II) trifluoroacetate with the hexafluorophosphate of the 6-aniline-5cyclopentadienyliron(II) cation under reflux in dry ethanol gives rise to N-mono- and N,N-disubstituted mercury-containing salts of this cation. The same mercury-containing salts have been synthesized by the action of mercury(II) trifluoroacetate on the deprotonation product of the (6-aniline)(5-cyclopentadienyl)iron(II) cation. Direct mercuration of the [6-(N,N-dimethylaniline)](5-cyclopentadienyl)iron(II) cation into the para position of the benzene ring of the arene ligand has been performed. The reactivity of the compounds obtained has been studied.  相似文献   
80.
The Cu(II) complexes with 4,6-bis(3,5-dimethyl-1H-pyrazole-1-yl)pyrimidine (L1) and 4-(3,5-dimethyl-1H-pyrazole-1-yl)-6-(3,5-diphenyl-1H-pyrazole-1-yl)pyrimidine (L2) of the composition Cu2L1Br4 and Cu2L2A4 (A = Cl, Br), respectively, were synthesized and studied by IR and magnetochemical methods. The molecular structure of the complexes is likely to be binuclear. In the presence of cocatalysts methylaluminoxane and triisobutylaluminium, the title complexes exhibit catalytic activity in the ethylene polymerization reaction. Original Russian Text ? M.B. Bushuev, V.P. Krivopalov, N.V. Semikolenova, Yu.G. Shvedenkov, L.A. Sheludyakova, G.G. Moskalenko, L.G. Lavrenova, V. A. Zakharov, S.V. Larionov, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 8, pp. 612–617.  相似文献   
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