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1.
N. I. Korotkikh A. V. Kiselev A. V. Knishevitsky G. F. Raenko T. M. Pekhtereva O. P. Shvaika 《Chemistry of Heterocyclic Compounds》2005,41(7):866-871
Efficient methods have been developed for obtaining precursors of stable carbenes, viz. 5-unsubstituted 3,4-diaryl-1,2,4-triazoles
and 3,3′- or 4,4′-bridge linked bis-1,2,4-triazoles, by the recyclization of 5-unsubstituted 1,3,4-oxadiazoles or p-phenylenebis-1,3,4-oxadiazole
with anilines or aromatic diamines in the presence of trifluoroacetic acid or with aniline hydrochlorides in pyridine.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1026–1032, July, 2005. 相似文献
2.
Green Chemistry has become in the last two decades an increasing part of research interest. Nonconventional «green» sources for chemical reactions include micro-wave, mechanical mixing, visible light and ultrasound. 1,2,3-triazoles have important applications in pharmaceutical chemistry while their 1,2,4 counterparts are developed to a lesser extent. In the review presented here we will focus on synthesis of 1,2,3 and 1,2,4-triazole systems by means of classical and « green chemistry » conditions involving ultrasound chemistry and mechanochemistry. The focus will be on compounds/scaffolds that possess biological/pharmacophoric properties. Finally, we will also present the formal cycloreversion of 1,2,3-triazole compounds under mechanical forces and its potential use in biological systems. 相似文献
3.
Alkylation of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with dialkyl sulfates or alkyl halides in the presence
of alkali proceeds with a low selectivity for the alkylating agent with the formation of two regioisomers at the N(1) and N(2) atoms of the heterocycle. Depending on the reaction conditions the proportion of the N(2) isomer was 14.6-33.8%.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1020–1025, July, 2005. 相似文献
4.
V. I. Kelarev M. A. Silin K. I. Kobrakov I. I. Rybina V. K. Korolev 《Chemistry of Heterocyclic Compounds》2003,39(6):736-743
N1-Phenyl- and N1-(3,5-dichloro-2-pyridyl)amidrazones have been synthesized by the reaction of imino esters of heterocyclic acids with phenyl- or (3,5-dichloro-2-pyridyl)hydrazine. Acylation of the products with acid chlorides leads to 1-phenyl- and 1-(3,5-dichloro-2-pyridyl)-3-hetaryl-5-R2-1H-1,2,4-triazoles. Compounds of this type are also formed by the condensation of N-acylimino esters of heterocyclic acids with phenyl- or (3,5-dichloro-2-pyridyl)hydrazine. 相似文献
5.
G. T. Sukhanov A. G. Sukhanova Yu. V. Sheikov 《Chemistry of Heterocyclic Compounds》2007,43(6):786-792
Interaction of N(1)-alkyl-substituted 3-nitro-5-R-1,2,4-triazoles with dialkyl sulphates proceeds selectively and results in the respective salts
of 1,4-dialkyl-, 1,4,5-trialkyl-3-nitro-1,2,4-triazoliums. The reaction of N(4)-alkyl-substituted 3-nitro-5-R-1,2,4-triazoles yields the mixtures of the salts of 1,4-dialkyl-, 1,4,5-trialkyl-3-nitro-1,2,4-triazoliums
and 1,4-dialkyl-, 1,3,4-trialkyl-1,2,4-triazol-5-ones with predominance of quaternary salts.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 927–934, June, 2007. 相似文献
6.
Dinneswara Reddy GudaTengjiao Wang Hyeon Mo ChoMyong Euy Lee 《Tetrahedron letters》2012,53(39):5238-5242
A mild, convenient, and efficient one-pot synthesis of mercapto-1,2,4-triazoles is described. Various hydrazides efficiently reacted with trimethylsilyl isothiocyanate (TMSNCS) under basic condition to give mercapto-1,2,4-triazoles in high yields. 相似文献
7.
V. A. Tartakovsky A. E. Frumkin A. M. Churakov Yu. A. Strelenko 《Russian Chemical Bulletin》2005,54(3):719-725
Thermal cyclization of 3-R-5-chloro-1,2,4-triazoles (R = Cl, Ph) afforded 2,6,10-tri-R- tris[1,2,4]triazolo[1,5-a:1′,5′c:1″,5″-e][1,3,5]triazines 5 (R = Ph) and 7 (R = Cl). These compounds are first representatives of this class of heterocycles, whose structures were unambiguously established. Treatment of these compounds with nucleophiles (H2O/NaOH, NH3) results in the triazine ring opening to give compounds consisting of three 1,2,4-triazole rings linked in a chain. For example, treatment of cyclic compound 5 with aqueous alkali affords 3-phenyl-1-3-phenyl-1-(3-phenyl-1H-1,2,4-triazol-5-yl)-1,2,4-triazol-5-yl-1H-1,2,4-triazol-5-one. Treatment of 3,7,11-triphenyltris[1,2,4]triazolo[4,3-a:4′,3′c:4″,3″-e][1,3,5]triazine (2) with HCl/SbCl5 leads to the triazine ring opening giving rise to 5-(3-chloro-5-phenyl-1,2,4-triazol-4-yl)-3-phenyl-4-(5-phenyl-1H-1,2,4-triazol-3-yl)-1,2,4-triazole. Thermal cyclization of the latter produces 3,7,10-triphenyltris[1,2,4]triazolo[1,5-a:4′,3′c:4″,3″-e][1,3,5]triazine (13). Thermolysis of both cyclic compound 2 and cyclic compound 13 is accompanied by the Dimroth rearrangement to yield 3,6,10-triphenyl-tris[1,2,4]triazolo[1,5-a:1′, 5′-c:4″,3″-e][1,3,5]triazine (14). Compounds 13 and 14 are the first representatives of cyclic compounds with this skeleton. 13C NMR spectroscopy allows the determination of the isomer type in a series of tris[1,2,4]triazolo[1,3,5]triazines.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 706–712, March, 2005. 相似文献
8.
V. M. Chernyshev V. A. Rakitov V. A. Taranushich V. V. Blinov 《Chemistry of Heterocyclic Compounds》2005,41(9):1139-1146
3-Acylamino-5-amino-1-R-1,2,4-triazoles are formed regioselectively on acylating 3,5-diamino-1-R-1,2,4-triazoles with an equimolar
amount of anhydrides, carboxylic acid chlorides, and sulfonyl chlorides. With an excess of anhydride and carboxylic acid chloride
3,5-diacylamino-1-R-1,2,4-triazoles are formed. 3-Acylamino-5-amino-1-R-1,2,4-triazoles do not interact with sulfonyl chlorides.
The higher reactivity of the 3-amino group towards acylating agents is determined by electronic and not steric factors.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1342–1350, September, 2005. 相似文献
9.
LU Ya-Lin ② GONG Xue-Dong JU Xue-Hai JI Guang-Fu XIAO He-Ming 《结构化学》2006,25(5):582-588
1 INTRODUCTION In the energetic material field, extensive attention was paid to insensitive compounds possessing not only high energetic density but also good stability. Previous studies[1] have shown that some small mo- lecular compounds such as azoles are good candi- dates for excellent explosives. For example, explo- sives containing triazole rings have the advantages of less molecular weight, high nitrogen content and density, good thermal stability, low impact sensiti- vity and large … 相似文献
10.
ESR and polarography of nitroazoles. 7. Anion-radicals of isomers of N-methyl-C-nitro-1,2,4-triazole
T. I. Vakul'skaya V. A. Shagun L. I. Larina V. A. Lopyrev 《Chemistry of Heterocyclic Compounds》2000,36(2):157-165
The anion-radicals of N-methyl-substituted 3-nitro-1,2,4-triazole have been studied by polarography, ESR, and quantum-chemical methods. The difference in electrochemical behavior of the N-methyl isomers of 3-nitro-1,2,4-triazole has been analyzed. The spin distributions in their anion-radicals have been investigated by quantum-chemical methods. The theoretical data obtained are in poor agreement with experiment. By varying the structural characteristics of the anion-radicals internal geometric parameters have been separated out which prove to have the greatest effect on spin distributions. Geometric structures were established for the investigated isomers by minimizing the functional describing the disagreement of the theoretical and experimental spin distributions on the magnetic nuclei. The calculated hyperfine structure constants for the magnetically active nuclei for the structures obtained were in good agreement with experiment. The influence of solvation effects on the electronic structure parameters of the nitrotriazole anion-radicals has been investigated. Hydrated complexes containing four molecules of water proved to be the most stable. Structural deformation of the solvated anion-radicals occurs in the same direction as on minimizing the functional.For part 6 see [1].Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk 664033, Russia; e-mail: vti@irioch.irk.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 193–202, February, 2000. 相似文献
11.
H. M. Dalloul N. S. Al-Abadla Kh. A. El-Nwairy 《Chemistry of Heterocyclic Compounds》2007,43(3):314-319
A new series of substituted 1,2,4-triazoles was synthesized from the cycloaddition reaction of alkanal and cycloalkanal hydrazones
containing electron-withdrawing groups (MeCO, PhCO, and MeOCO) with appropriate hydrazonoyl halides.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 392–398, March, 2007. 相似文献
12.
Beresnev D. G. Rusinov G. L. Ponomareva A. Yu. Chupakhin O. N. 《Russian Chemical Bulletin》2003,52(10):2161-2166
Recyclization of the addition products of alkylureas to 3-aryl-1,2,4-triazin-5(2H)-ones affording 1,2,4-triazole derivatives was found to occur in Ac2O. 相似文献
13.
14.
Synthesis and Antibacterial Activity of Some New Derivatives of Thiosemicarbazide and 1,2,4-Triazole
Monika Wujec Anna Pachuta-Stec Joanna Stefańska Edyta Kuśmierz Agata Siwek 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1661-1669
Abstract In a reaction of hydrazides of cyclohexylacetic acid 1 and phenylacetic acid 2 with isothiocyanates, respective thiosemicarbazide derivatives 3–18 were obtained. Further cyclization with 2% NaOH led to the formation of 5-(cyclohexylmethyl/benzyl)-4-substituted-2,4-dihydro-3H-1,2,4-triazole-3-thiones 19–34. Structures of all new products were confirmed by analytical and spectroscopic methods. All compounds were screened for their in vitro activity against some species of bacteria and fungi. [Supplementary materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables.] 相似文献
15.
V. M. Chernyshev V. A. Rakitov V. V. Blinov V. A. Taranushich Z. A. Starikova 《Chemistry of Heterocyclic Compounds》2009,45(4):436-444
Alkylation of 3-acylamino-, 5-amino-1-phenyl-3-tosylamino-1,2,4-triazoles and 3,5-diacetylamino-1-phenyl-1,2,4-triazole in
the presence of an equimolar amount of sodium methylate in DMSO occurs regioselectively at the amide (sulfamide) group nitrogen
atom. The benzylation of 3-acetylamino-5-amino-1-phenyl-1,2,4-triazole with excess base and benzyl chloride also alkylates
the amino group at position 5. Alkylamino-1-R-1,2,4-triazoles can be conveniently prepared by alkylation of the corresponding
acetylamino-1,2,4-triazoles in the presence of base and subsequent acid hydrolysis of the N-acetyl-N-alkyl derivatives.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 557–567, April, 2009. 相似文献
16.
Safa Azzouni Abderrahmen Abdelli Anne Gaucher Youssef Arfaoui Mohamed Lotfi Efrit Damien Prim 《Tetrahedron》2018,74(49)
The reaction of variously substituted acylimidates with hydrazine derivatives represents an efficient and easy to set synthetic entry towards 5-vinyl-1,2,4-triazole derivatives. The construction of the triazole ring allows the installation of variety of substituent combination at the N(1), C(3) and C(5) positions of the five-membered heterocycle in good to high yields. The method reveals selective towards 5-vinyl-1,2,4-triazoles avoiding the potential formation of seven- and five-membered side-products as supported by theoretical calculations and NMR experiments. First lines of Pd-catalyzed arylation of the vinyl fragment towards 5-styryl-1,2,4-triazoles and Cu-catalyzed arylation at the N(1) site are finally described. 相似文献
17.
A. G. Sukhanova G. V. Sakovich G. T. Sukhanov 《Chemistry of Heterocyclic Compounds》2008,44(11):1368-1373
Reaction of 3-nitro-1,2,4-triazole and 5-methyl-3-nitro-1,2,4-triazole with secondary and tertiary alcohols in conc. H2SO4 takes place at the N(2) atom. Alkylation by 2-propanol occurs regioselectively to form the 1-isopropyl-3-nitro-and 1-isopropyl-3-methyl-5-nitro-1,2,4-triazoles.
As a consequence of isomerization the alkylation using cyclohexyl or tert-butyl alcohols gives respectively a mixture of regioisomers
substituted at atom N(1) (1-cyclohexyl-3-nitro-and 1-cyclohexyl-5-methyl-3-nitro-1,2,4-triazoles) and at atom N(2) (5-nitro-1-cyclohexyl-and
1-cyclohexyl-3-methyl-5-nitro-1,2,4-triazoles) and, in the second case, to 1-tert-butyl-3-nitro-1,2,4-triazole.
* For Communication 5 see [1].
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1680–1687, November, 2008. 相似文献
18.
19.
Dr. Davin G. Piercey Dr. David E. Chavez Dr. Brian L. Scott Dr. Greg H. Imler Dr. Damon A. Parrish 《Angewandte Chemie (International ed. in English)》2016,55(49):15315-15318
The reaction of 3‐amino‐5‐nitro‐1,2,4‐triazole with nitrous acid produces the corresponding diazonium salt. When the diazonium salt is treated with nitroacetonitrile, a subsequent condensation and cyclization reaction occurres to produced 4‐amino‐3,7‐dinitrotriazolo‐[5,1‐c][1,2,4] triazine (DPX‐26). X‐ray crystallographic analysis shows that the DPX‐26 has a density of 1.86 g cm?3, while it is calculated to have a heat of formation of 398.3 kJ mol?1. DPX‐26 is predicted to approach the explosive performance of RDX but displays significantly better safety properties. Oxidation of DPX‐26 using hypofluorous acid produces 4‐amino‐3,7‐dinitrotriazolo‐[5,1‐c][1,2,4] triazine 4‐oxide (DPX‐27), which is also predicted to be a high‐performance material with enhanced safety properties. 相似文献
20.
Javier de Mendoza Tomás Torres M. Dolores Badía 《Monatshefte für Chemie / Chemical Monthly》1988,119(8-9):1041-1045
Lead tetraacetate oxidation of 4-amino-1,2,4-triazoles, 1-amino- and 2-amino-1,2,3-triazoles affords mainly fragmentation to nitriles or acetylenes, even in the presence of intramolecularly attached double bonds.
Über die Bleitetraacetatoxidation von 4-Amino-1,2,4-triazolen, 1-Amino- und 2-Amino-1,2,3-triazolen (Kurze Mitteilung)
Zusammenfassung Bei der Oxidation von 4-Amino-1,2,4-triazolen, 1-Amino- und 2-Amino-1,2,3-triazolen mit Bleitetraacetat entstanden hauptsächlich Nitrile bzw. Acetylene durch Fragmentierung — trotz der Gegenwart von intramolekularen Doppelbindungen.相似文献