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1.
The reaction of carbonyl derivatives of diazoacetonitrile with hydrogen sulfide in the presence of triethylamine yields 4-substituted 5-amino-1,2,3-triadiazoles. Under analogous conditions, hydrogen selenide and ethyl mercaptan reduce the starting diazo compounds to hydrazones. Thiadiazoles are recyclized to 4-substituted 5-mercapto-1,2,3-triazoles by the action of bases.For 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 691–696, May, 1986.  相似文献   

2.
3.
A method for the synthesis of 2-diazo-2-cyanoacetazide was developed, and its reaction with various nucleophilic reagents was investigated. 5-Halo-1H-1,2, 3-triazole-4-carboxazides and their 4-carbamoyl and 4-ethoxycarbonylamino derivatives were obtained.See [1] for Communication 4.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1503–1508, November, 1987.  相似文献   

4.
1,2,3-Triazol-5-olates are formed in the reaction of diazomalonodiamide and 2-diazo-2-cyanoacetic acid amide and N-methylamide with sodium ethoxide, triethylamine, and ammonia. The products of the reaction of 2-diazo-2-cyanoacetamide with primary amines are mixtures of 4-cyano-1,2,3-triazol-5-olates and 5-amino-1-alkyl-1,2,3-triazole-4-carboxamides.See [1] for communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 926–931, July, 1986.  相似文献   

5.
5-Amino-1,2,3-thiadiazole-4-carbothioamides were obtained in the reaction of carbonyl derivatives of diazoacetonitrile with P4S10 and the Lawesson reagent. A novel recyclization of 1,2,3-thiadiazole-4-carbothioamides was observed.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 845–849, June, 1987.  相似文献   

6.
Carbonyl-substituted derivatives of diazoacetonitrile have been obtained by the diazotization of amines and by diazo-group transfer which, under the action of hydrogen halide, have been converted into 4-carbonyl-substituted 5-halo-1H-1,2, 3-triazoles. The structures of these compounds have been confirmed by mass spectrometry and independent synthesis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1266–1270, September, 1984.  相似文献   

7.
The thermal behavior of 5-hydroxy-1,2,3-triazole-4-carboxamides obtained on acidification of solutionns of triazol-5-olates has been investigated. A new rearrangement has been discovered in the 1,2,3-triazole series and the qualitative effect of the substituents in the initial triazole and of temperature have been clarified.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1208–1213, September, 1992.  相似文献   

8.
The previously unknown recyclization of nitrobenzo[d]isoxazoles into 1,2,3-triazoles was found. A general method for the synthesis of 2-aryl-4-(2-hydroxy-4-nitro-6-R-phenyl)-1,2,3-triazoles from 4-R-6-nitrobenzo[d]isoxazole-3-carbaldehyde arylhydrazones was developed.  相似文献   

9.
Quantum-chemical calculations have been carried out on molecular electrostatic potentials, proton affinity in the gas phase, gas phase basicity, and pK BH+ values in aqueous solution for C-nitro- and N-alkyl-4(5)-nitro-1,2,3-triazoles, and the relative stability of the isomeric N-alkyl-4(5)-nitrotriazoles (alkyl = Me, Et, i-Pr, t-Bu) in the gas phase and in aqueous solution. For all the studied substances in the gas phase the 2H-tautomer and the N(2)-isomers were considerably more stable than the corresponding N(1) compounds, and the 3H-tautomer and N(3)-isomer were the least stable. In aqueous solution 1- and 3-isomers had close values of energies, but in the case of C-nitro-1,2,3-triazole the 1H form became even more stable than the 2H-form. It was established which ring nitrogen atoms of 1,2,3-triazoles are protonated in the gas phase and in solution. The obtained data correlate well with the results of experimental investigations on the alkylation of 1,2,3-triazoles in acidic and basic media and of the experimental investigation on the alkylation of C-nitro-1,2,3-triazoles with diethyl sulfate carried out in the present work. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1816–1828, December, 2008.  相似文献   

10.
The Schiff base (HLBr), containing a chelating unit and triphenylphosphonium moiety has been synthesized in the reaction of 4-aminobenzyl(triphenyl)phosphonium bromide with 5-hydroxy-3-methyl-1-phenyl-4-formylpyrazole. The composition and structure of HLBr have been determined by elemental analysis, IR, 1D and 2D NMR, electronic spectroscopy and mass spectrometry. Density functional theory (DFT) calculations (6-311G(d,p) level of theory) have been carried out to investigate tautomeric forms of HL+ and the reaction mechanism of its formation and spectral properties. The most stable form in the solid state and in DMSO solution is pyrazolone (keto-amine) tautomeric form.  相似文献   

11.
The reaction of 2-chlorobenzaldehyde with cyanothioacetamide and dibenzoylmethane in the presence of piperidine or N-methylmorpholine gave the corresponding 5-benzoyl-4-(2-chlorophenyl)-3-cyano-6-hydroxy-6-phenyl-1,4,5,6-tetrahydropyridine-2-thiolates, used in the synthesis of 1-alkylthio-4-benzoyl-1-benzoylamino-3-(2-chlorophenyl)-2-cyanobut-1-enes.  相似文献   

12.
Reaction of N-fluoropyridinium fluoride generated in situ with a series of isonitriles and diazo compounds led to the formation of the corresponding (pyridine-2-yl)-1H-1,2,3-triazoles in good yields (37-59%). Best outcome was consistently achieved with both aromatic isonitriles and stabilized diazo derivatives. The proposed reaction mechanism involves the intermediate formation of a highly reactive carbene species.  相似文献   

13.
Several chemoselective syntheses have been developed for 4-nitro-1,2,3-triazoles from sodium azide and gem-dinitroethylenes prepared from readily available transformation products of dinitroacetic acid ester: N-(,-dinitroethyl)-N,N-dialkylamines, 2,2-dinitroethanol acetate, a mixture of dinitroacetic acid ester with aliphatic aldehydes, or 1,1,1-trinitroalkanes. Hitherto-unknown 4-nitro-5-amino- and 4,5-dinitro-1,2,3-triazoles have been synthesized via successive transformations of the CH3 groups in 5-nitro-4-methyltriazole. Nitration of 4-nitro-1,2,3-triazole with nitronium fluoroborate or acetyl nitrate gave an unknown 2,4-dinitro-1,2,3-triazole.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 958–966, April, 1992.  相似文献   

14.
为了寻找新型高效低毒的农药先导化合物,采用1-[(杂芳基)甲基]-5-甲基-1H-1,2,3-三唑基-4-甲酰氯与2-氨基-5-烷基-1,3,4-噻二唑的缩合反应,合成了8种未见文献报道的目标化合物,其结构经IR,1H NMR和元素分析确证,部分化合物还经MS的进一步证实.初步的生物活性测试结果表明,部分目标化合物在100 mg/L浓度下对双子叶植物(油菜)显示出中等的除草活性和一定程度的杀虫活性(250 mg/L).  相似文献   

15.
16.
Summary. The bromination of 2-styrylchromones, bearing electron neutral substituents, with two molar equivalents of piridinium tribromide gave 2-(2-aryl-1,2-dibromoethyl)chromones and 3-bromo-2-(2-aryl-1,2-dibromoethyl)chromones. The presence of electron-donating substituents on their B ring led to a mixture of compounds due to the higher reactivity of their C(2)=C(3) and C=C double bonds, whereas the strongly electron-withdrawing group hindered the bromination. The dehydrobromination of 2-(2-aryl-1,2-dibromoethyl)chromones with triethylamine gave a diastereomeric mixture of (E)- and (Z)-2-(-bromostyryl)chromones. Some novel 4(5)-aryl-5(4)-(2-chromonyl)-1,2,3-triazoles have been obtained from the reactions of 2-(2-aryl-1,2-dibromoethyl)chromones, 2-(-bromostyryl)chromones, and 2-styrylchromones with sodium azide. The reactions of 2-styrylchromones with sodium azide are more efficient, general, and constitute a one-pot synthetic method of 4(5)-aryl-5(4)-(2-chromonyl)-1,2,3-triazoles allowing the preparation of 1,2,3-triazoles bearing either electron-donating or electron-withdrawing substituents in their aryl ring. The structure of all new compounds was established by extensive NMR spectroscopic studies.  相似文献   

17.
18.
The condensation of 2-chlorobenzaldehyde with cyanothioacetamide and 2-thenoyltrifluoroacetone in the presence of N-methylmorpholine takes place stereoselectively and leads to the formation of N-methylmorpholinium 4,5-trans-4-(2-chlorophenyl)-3-cyano-6-hydroxy-5-(2-thenoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine-2-thiolate. The latter was used to synthesize the corresponding 2-alkylthiotetrahydropyridines. The structure of 4,5-trans-4-(2-chlorophenyl)-3-cyano-6-hydroxy-2-methallylthio-5-(2-thenoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine was determined by X-ray crystallographic analysis.  相似文献   

19.
Proof‐of‐principle is reported for a directed functionalization and derivatization of chalcogenidometallate cages with respect to the formation of hybrid compounds containing (M)/T/E semi‐conductor nodes (M=Cu; T=Ge, Sn; E=S). In their Full Paper on page 6595 ff. , S. Dehnen et al. show how it is possible to generate functionalized ternary CuSnS or CuGeS clusters and to transfer COMe ligands into CR(N–NH2) or CR(N–NHPh) terminal groups by reaction of a series of novel, functionalized thiometallate cages [(RT)nSm] (n/m=4/6, 3/4), the R ligands of which are terminated by COO(H) or COMe.

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20.
To develop a method of synthesis of the potentially physiologically active compounds, 1′-substituted 6-amino-spiro-4-(piperidine-4′)-2H,4H-pyrano[2,3-c]pyrazoles, we studied the three-component condensation of substituted piperidin-4-ones, malononitrile and pyrazolin-5-ones. It was found that the electrochemical method of synthesis is more regioselective, the products of the reaction are analytically pure and do not require further recrystallization.  相似文献   

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