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1.
2-Nitroguanidine reacts with dicarboxylic acid dihydrazides to form intermediate condensation product which undergoes intramolecular cyclization, yielding the corresponding bis(3-nitroamino-1,2,4-triazol-5-yl)alkanes and 5,5-bi(3-nitroamino-1,2,4-triazole) potassium salt. The structure of the products was confirmed by comparing their electron absorption spectra with those of 3,5-bis(nitroamino)-1,2,4-triazole salts.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1464–1466.Original Russian Text Copyright © 2004 by Metelkina, Novikova, Berdonosova, Berdonosov, Grineva.For communication VI, see [1].  相似文献   
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A new synthetic procedure was developed to obtain 1-hydroxymethyl-2-nitroguanidine from 2-nitroguanidine and formaldehyde without catalyst. Reactions of 2-nitroguanidine and its 1-methyl-and 1-phenylsubstituted derivatives with formaldehyde and urotropin under acid catalysis resulted in 4-nitriminotetrahydro-1,3,5-oxadiazine and 2-nitriminohexahydro-1,3,5-triazine and their methyl-and phenyl-substituted derivatives, whose nitration with concn. HNO3 in the presence of acetic anhydride and concn. H2SO4 depending on the temperature conditions led to the formation of 4-nitrimino-3,5-dinitrotetrahydro-1,3,5-oxadiazine, 3-methyl-4-nitrimino-5-nitrotetrahydro-1,3,5-oxadiazine, 2-nitrimino-5-nitrohexahydro-1,3,5-triazine, and 1,3,5-trinitro-hexahydro-1,3,5-triazine-2-one.  相似文献   
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A new procedure for the synthesis of 5(3)-nitroamino-1,2,4-triazole-3(5)-carboxylic acid and 5,5′ -bi(3-nitroamino-1,2,4-triazole) potassium salt has been developed. It includes cyclization of [2-(N2-nitro-carbamimidoyl) hydrazino]oxoacetic acid and 2,2′-bis(N 2-itrocarbamimidoyl)oxalohydrazide, respectively, which are prepared by reaction of 1-amino-2-nitroguanidine with oxalic acid. The reaction of 5(3)-nitroamino-1,2,4-triazole-3(5)-carbohydrazide with 1-methyl-2-nitro-1-nitrosoguanidine leads to N′ -(N 2-nitrocarbamimidoyl)-5(3)-nitroamino-1,2,4-triazole-3(5)-carbohydrazide whose intramolecular cyclization in the presence of bases may be regarded as a new method of synthesis of 5,5′-bi(3-nitroamino-1,2,4-triazole) salts.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 3, 2005, pp. 447–450.Original Russian Text Copyright © 2005 by Metelkina, Novikova, Berdonosova, Berdonosov.For communication VIII, see [1].  相似文献   
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Alumina- (5 and 10 wt%) doped zirconia samples were prepared by sol-gel processing of aluminum sec-butoxide and zirconium butoxide in the presence of acids (acetic, sulfuric or nitric acid) or organic additives (Pluronic P123). X-ray absorption spectroscopy, X-ray diffraction and nitrogen adsorption experiments showed that the structure of the synthesized mixed oxides is strongly influenced by the chemical synthesis parameters.  相似文献   
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The reaction of glyoxal with N′-nitrohydrazinecarboximidamide (1-amino-2-nitroguanidine) in the presence of sodium hydroxide at a molar ratio of 1 : 1 : 1 gave N′-nitro-2-(2-oxoethylidene)hydrazinecarboximidamide as a mixture of syn and anti isomers, whereas at a reactant ratio of 1:2:2 N′-nitro-2-[(5-nitroamino-2H-1,2,4-triazol-3-yl)methyl]hydrazinecarboximidamide and 3-nitroamino-4,5-dihydro-1,2,4-triazin-5-ol were formed. N′-Nitro-2-(2-oxoethylidene)hydrazinecarboximidamide reacted with N′-nitrohydrazinecarboximidamide in boiling ethanol to give N′-nitro-2-[(5-nitroamino-2H-1,2,4-triazol-3-yl)methyl]hydrazinecarboximidamide, while in glacial acetic acid 2,2′-(ethane-1,2-diylidene)bis(N′-nitrohydrazinecarboximidamide) was obtained. The latter was also formed in the reaction of glyoxal with N′-nitrohydrazinecarboximidamide in acetic acid at room temperature. The reaction of 2-methylidene-N′-nitrohydrazinecarboximidamide with glyoxal led to the formation of 3-nitroimino-2,3,4-5-tetrahydro-1,2,4-triazine-5-carbaldehyde or 1-(methylideneamino)-2-(nitroimino)imidazolidine-4,5-diol, depending on the conditions.  相似文献   
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Summary. Reaction of Ti(OEt)4 with lysine results in the formation of Ti(OEt)3(lysinate), as previously reported. Contrary to that, Al(OsBu)3 only catalyzes the formation of 3-aminocaprolactam, and no substitution product was observed. The reaction of Zr(OBu)4 with lysine at room temperature produced both 3-aminocaprolactam and Zr(OBu)3(lysinate); the lysinate complex was not observed when the reaction was performed at elevated temperatures.Received February 17, 2003; accepted February 21, 2003 Published online June 12, 2003  相似文献   
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