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1.
The degree of charging of a nickel oxide electrode composed of spherical nickel hydroxide in a nickel-zinc battery was studied in anodic oxidation of the electrode in KOH solutions of different concentrations, containing hydroxozincate ions.  相似文献   
2.
The nucleophilic reactivity of amines of the norbornane, norbornene, and adamantane series toward ptoluenesulfonyl chloride and diphenyl chlorophosphate in acetonitrile at 25°C is determined mainly by the steric factor. Parameters characterizing spatial accessibility of the reaction center in the amine molecule have been determined. Cage-like substituents show no appreciable effect on the amine reactivity, as compared to common alkyl groups.  相似文献   
3.
Epoxidation of 1-substituted 3-cyclohexenes was investigated. The stereoisomeric composition of the forming epoxides mixture was established by means of GLC and 1H NMR spectroscopy. The spectral parameters of the epoxides are considered. The thermodynamical stability of cis- and trans-epoxides was evaluated by molecular mechanics method. For the epoxidation of 1-substituted 3-cyclohexenes with peracetic acid was carried out a quantum-chemical calculation of the potential energy surface by PM3 method.  相似文献   
4.
Reactions of previously known and newly synthesized N-(bicyclo[2.2.1]hept-5-en-endo-2-ylmethyl)arenesulfonamides with monoperoxyphthalic acid generated in situ from phthalic anhydride and 30% hydrogen peroxide lead mostly to the corresponding N-arylsulfonyl-exo-2-hydroxy-4-azatricyclo[4.2.1.03,7]nonanes (azabrendanes). In some cases, N-(exo-5,6-epoxybicyclo[2.2.1]hept-5-en-exo-2-ylmethyl)arenesulfonamides were isolated as the only products or mixtures of alternative oxidation products were obtained. The presence of electron-acceptor nitro groups in the benzene ring and bulky substituents, primarily in the ortho position, is considered to be a structural factor preventing the primary oxidation products (epoxy derivatives) from undergoing heterocyclization.  相似文献   
5.
Electrochemical and working characteristics of a nickel-zinc battery with nickel oxide electrode made of spherical nickel hydroxide on foamed nickel support were determined.  相似文献   
6.
A synthesis was accomplished of 4-azatricyclo[5.2.1.02,6]dec-8-ene by aminolysis of bicyclo[2.2.1]hept-2-ene-endo,endo-5,6-dicarboxylic acid anhydride followed by transformation of amidoacid into imide that was subsequently reduced by lithium aluminum hydride. The reaction of the key tricyclic amine with sulfonyl chlorides afforded N-[aryl(benzyl, cyclohexyl, propyl)sulfonyl]-4-azatricyclo[5.2.1.02,6]dec-8-enes.The sulfonamides were subjected to epoxidation with perphthalic acid. By reaction of sulfonamides with p-nitrophenyl azide triazolines were obtained. The structure of compounds synthesized was confirmed by IR, 1Hand 13 NMR spectra.  相似文献   
7.
The review considers reactions of alicyclic epoxy compounds and their analogs with nitrogen-containing nucleophilic reagents, such as amines, azides, hydrazines, etc., biological aspects of these reactions, and properties of amino alcohols which are practically important organic products and synthons. Reaction mechanisms, including radical and radical ion reaction paths, the results of quantum-chemical studies, stereo- and regioselectivity aspects, and activation of epoxy substrates with achiral and chiral catalysts are discussed. The formation of nitrogen-containing heterocyclic systems via opening of the oxirane ring is described.  相似文献   
8.
The review covers the reactivity of spirooxiranes. The characteristic distinction of chemical behavior of this type epoxides from that of epoxycycloalkanes is discussed. In the spirooxiranes unlike epoxycycloalkanes the oxirane and alicyclic fragments are joined by one and not by two common atoms. The spirooxiranes are characterized by enhanced reactivity in the neutral and alkaline media, and also by versatile isomerizations and rearrangements in the presence of acidic catalysts. The relation between the chemical properties of spirooxiranes and the features of their electronic structure was considered. The main reactions of spirooxiranes with reductants, reactants with nucleophilic centers on oxygen, sulfur, carbon, nitrogen, and phosphorus, and with hydrogen halides are analyzed. The isomerization of spirooxiranes into carbonyl compounds and allyl alcohols is discussed. The possibility was considered of formation of the other cyclic systems proceeding from spirooxiranes.  相似文献   
9.
The dependence of capacity and service life of a nickel-zinc battery on the mechanism of zinc transfer and the rate of zinc intercalation into nickel oxide electrodes differing in the conductivities of the active paste and porous structures was studied.  相似文献   
10.
A synthesis of new N-(arylsulfonyl)-5-aminomethylbicyclo[2.2.1]hept-2-enes obtained by reaction of stereoisomeric exo- and endo-5-aminomethylbicyclo[2.2.1]hept-2-enes with arylsulfonyl chlorides is described. With the use of the data of 1H and 13C NMR spectra, including those of two-dimensional spectra recorded in COSY and NOESY mode, the contribution of stereochemical features of sulfonamides into the spectra structure of endo- and exo-isomers was evaluated. Applying various methods of the phase-transfer catalysis alkylation and acylation of the stereoisomeric arylsulfonamides containing a norbornene fragment was carried out. The reactions of alkylated stereoisomeric sulfonamides, N-(benzyl)-N-(3,4-dichlorophenylsulfonyl)-5-aminomethylbicyclo[2.2.1]hept-2-enes, with peroxyphthalic acid provide epoxides; the orientation of substituents in the cage norbornene fragment does not affect the direction of the process. The structure of the products obtained by sulfonamides transformations was confirmed by IR, 1H and 13C NMR spectra.  相似文献   
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