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1.
Preparation of ultradispersed transition metals (20–100 nm) by reduction of metal complexes in molecular microreactors (cavities of immobilized calixarenes, polyelectrolytes) was studied.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1914–1916.Original Russian Text Copyright © 2004 by Altshuler, Sapozhnikova.  相似文献   
2.
1.  The reaction of -nitrocinnamic esters with methanol proceeds at room temperature and in the absence of base; the addition of acetic acid sharply retards the rate of the addition reaction.
2.  The introduction into the -position of -nitroacryl esters of radicals containing an unshared pair of electrons on the nitrogen (3-indolyl, anilino, dimethylamino) depresses the electrophilic character of the C=C bond in these compounds, and they do not react with alcohols under analogous conditions.
3.  N-Acylated -nitrovinylindole is deacylated under mild conditions under the action of alcohols.
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3.
A study was carried out of alkylation, acylation and aminomethylation reactions were studied in the 5-alkyl-4,5-dihydro-1,2,4-triazin-4-one series. Alkylation by alkyl halides proceeds in the presence of sodium methylate at the N (1) and N (4) atoms with the formation of a mixture of alkylated compounds of three types: derivatives of 4,5-dihydrotriazine, unsaturated triazine, and their dimers. Acylation with isocyanates leads to the formation of heterocyclic ureas — derivatives at the N (4) atom. Mono- and bisaminals were obtained by the reaction of triazines with ethoxymethyldiethylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–970, July, 1991.  相似文献   
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New sulfonic cation exchangers based on immobilized calix[4]resorcinolarenes were prepared. Their ion-exchange properties toward Na+, Cu2+, [Pd(NH3)4]2+, In3+, and Sn4+ ions were studied in a wide pH range, and their chemical stability was examined.  相似文献   
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Chemistry of Heterocyclic Compounds - A series of azolo[5,1-c][1,2,4]triazines containing a cyano group were prepared as analogs of the drug Triazavirin (riamilovir). Sodium...  相似文献   
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New phosphoric acid cation exchanger was synthesized on the basis of immobilized calix[4] resorcinolarene and its service characteristics were determined.  相似文献   
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The ion-exchange equilibrium of protons in SO3H groups of a sulfonic cation exchanger based on immobilized cis-tetraphenylcalix[4]resorcinolarene with cations of Li+, Na+, Ag+, Cu2+, In3+, and protonated 1,3,5,7-tetraazaadamantane in aqueous solutions of electrolytes at 293 K was studied. The corrected coefficients of the cation exchange selectivity were calculated.  相似文献   
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