首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 796 毫秒
1.
The chemical stability of alkoxy-NNO-azoxy compounds to reduction with hydrazine hydrate has been studied. Methoxy-NNO-azoxymethane and bis(methyl-ONN-azoxy) formaldehyde acetal are more stable by orders of magnitude than bis(methoxy-NNO-azoxy)methane and 2,2-bis(methoxy-NNO-azoxy)propane. Methoxy-NNO-azoxymethane is also resistant to reduction with titanium(III) under acidic conditions and with iron(II) under basic conditions. Probable reaction mechanisms have been proposed on the basis of the substrate reactivity toward nucleophiles, acids, and alkalies.  相似文献   

2.
A new approach to the synthesis of 4-amino-5-(tert-butyl-NNO-azoxy)-2-R-2H-1,2,3-triazole 1-oxides 1 was developed. Compounds 1 were obtained by reactions of 3-amino-4-(tert-butyl-NNO-azoxy)furoxan with aliphatic amines RNH2 (R = Me, Et, Pri, Bu, and But). 4-Amino-5-(tert-butyl-NNO-azoxy)-2-tert-butyl-2H-1,2,3-triazole 1-oxide was transformed under the action of acids into 4-amino-5-(tert-butyl-NNO-azoxy)-1-hydroxy-1H-1,2,3-triazole. Methylation of the latter with diazomethane mainly involves the O atom of the triazole oxide ring. Reduction of compounds 1 gave 4-amino-5-(tert-butyl-NNO-azoxy)-2-R-2H-1,2,3-triazoles and 4-amino-5-(tert-butyldiazenyl)-2-R-2H-1,2,3-triazoles (R = Me, Pri, and But). The structures of the compounds obtained were confirmed by 1H, 13C, and 14N NMR spectroscopy.  相似文献   

3.
2,2-Bis(alkoxy-NNO-azoxy)propane-1,3-diols reacted with thionyl chloride to give previously unknown 5,5-bis(methoxy-NNO-azoxy)- and 5,5-bis(ethoxy-NNO-azoxy)-1,3,2-dioxathiane 2-oxides. Replacement of the hydroxy groups by chlorine is a minor reaction path. According to the X-ray diffraction data, the heteroring in the molecule of 5,5-bis(methoxy-NNO-azoxy)-1,3,2-dioxathiane 2-oxide adopts a chair conformation with axial orientation of the S=O bond.  相似文献   

4.
The first representative of the alkoxy-NNO-azoxy olefin series, viz., methoxy-NNO-azoxyethene, was synthesized by the pyrolysis of 1,1-bis(methoxy-NNO-azoxy)ethane.  相似文献   

5.
《Mendeleev Communications》2021,31(6):792-794
Three novel energetic furazans with a cyano-NNO-azoxy group were synthesized using cyanamide and 2,2,2-tri- fluoro-N-(4-nitrosofurazan-3-yl)acetamide as the starting compounds. (Cyano-NNO-azoxy)furazans obtained display high experimental enthalpies of formation (+742 to +1073 kcal kg−1), good thermal stability (Tonset = 193–222 °C) and moderate mechanical sensitivity. These compounds may be of interest as energetic fillers in solid fuels for ramjet engines and in solid composite propellants.  相似文献   

6.
Hydrolysis rate of alkoxy-NNO-azoxy compounds like di(methoxy-NNO-azoxy)methane I, di-(methyl-NON-azoxy)formal II, di(methoxy-NNO-azoxy)methane III, and 2,2-di(methoxy-NNO-azoxy)propane IV in 5 M KOH solution was measured by manometric method at 80°C; rates relation is 1:40:540:10. Reversible deprotonation to form C-anions followed by their rapid decomposition is a presumable mechanism for compounds I–III. Nucleophilic attack of OH-anion on the carbon atom of CH3ON=N(O) group is the most probable first stage of hydrolysis in the case of compound IV.  相似文献   

7.
1,1-Bis(methoxy-NNO-azoxy)alkanes were alkylated in high yield at the central carbon atom under conditions of phase-transfer catalysis with selective formation of mono- and dialkyl derivatives.  相似文献   

8.
《Mendeleev Communications》2021,31(6):789-791
Novel energetic azoxy- and azofurazans bearing nitro-NNO- azoxy and amino groups were synthesized using the ammonolysis of some known (nitro-NNO-azoxy)furazans. 3-Amino-4-{[4′-(nitro-NNO-azoxy)f urazan-3′-yl]-NNO- azoxy}furazan displays the highest melting point (114 °C, decomp.) among the known (nitro-NNO-azoxy)furazans, optimal density (1.80 g cm−3), high experimental enthalpy of formation (639 kcal kg−1) and mechanical sensitivity on the level of PETN. In terms of the specific impulse level, the model solid composite propellant formulations based on this compound outperform similar formulations based on RDX, HMX or CL-20 by 7–12 s.  相似文献   

9.
Reactions of 3(4)-amino-4(3)-(tert-butyl-NNO-azoxy)furoxans with excess (NO2)2S2O7 or with a HNO3—H2SO4—Ac2O mixture unexpectedly produce [1,2,5]oxadiazolo[3,4-e]?[1,2,3,4]tetrazine 4,6-di-N-oxide (furazanotetrazine dioxide) and products of amino group oxidation (mainly to the corresponding azofuroxans) instead of the expected furoxanotetrazine dioxides. In some cases, individual (Z)-3,3´-((E)-diazene-1,2-diyl)-bis-((Z)-2-tert-butyl-1-oxidodiazenyl)-1,2,5-oxadiazole 2-oxide) was isolated. Formation of furazanotetrazine dioxides was observed in the reaction of 3-nitramino-4-(tert-butyl-NNO-azoxy)furoxan sodium salt with H2SO4 in Ac2O. Quantum chemical calculation at the DFT/B3LYP/6-31G(d) level of theory was used to estimate several aspects of the reactivity of 3(4)-nitramino-4(3)-(tert-butyl-NNO-azoxy)furoxans in a comparison with 3(4)-nitramino-4(3)-phenylfuroxans and the possible causes of the observed transformations were revealed.  相似文献   

10.
3-Amino-4-(tert-butyl-NNO-azoxy)furoxan (1a) and 4-amino-3-(tert-butyl-NNO-azoxy)-furoxan (1b) and their acetyl derivatives 6a,b were obtained. The equilibria 1a ai 1b and 6a ? 6b were studied. Furoxan 6b can undergo thermal rearrangement into 3-[(tert-butyl-NNO-azoxy)(nitro)methyl]-5-methyl-1,2,4-oxadiazole (7), prolonged heating of which gives N-(2-tert-butyl-5-nitro-1-oxido-2H-1,2,3-triazol-4-yl)acetamide (8). With the transformation 78 as an example, the possibility of participation of the azoxy group in the Boulton-Katritzky rearrangements was demonstrated for the first time.  相似文献   

11.
A new method for the synthesis of benzotetrazine-1,3-dioxides was developed from the 2-(tert-butyl-NNO-azoxy)-N-nitroaniline O-alkyl derivatives upon the action of strong acids (H2SO4, MeSO3H, CF3CO2H) or BF3·Et2O. A mechanism suggested for these reactions includes transformation of the N=N(O)OR group (R = Me, Pri) to the oxodiazonium ion (N=N=O)+, which intramolecularly reacts with the neighboring tert-butyl-NNO-azoxy group, furnishing the tetrazine-1,3-dioxide ring.  相似文献   

12.
Reaction of bis(methoxy-NNO-azoxy)methane with formaldehyde in ethanol gives 3-ethoxy-2,2-bis(methoxy-NNO-azoxy)propan-1-ol as a minor product along with target 2,2-bis(methoxy-NNO-azoxy)ethanol. The structure of the former was confirmed by the counter synthesis and X-ray diffraction analysis.  相似文献   

13.
A new method for the synthesis of benzotetrazine-1,3-dioxides was developed, which involves the reaction of 2-(tert-butyl-NNO-azoxy)-N-nitroanilines with the Ac2O/H2SO4 system. This method was also used for the synthesis of [1,2,5]oxadiazolo[3,4-c]cinnoline-5-oxide from 3-nitramino-4-phenylfurazan. The suggested mechanism of these reactions involves the formation of the intermediate oxodiazonium ion, resulting from acetylation of the oxygen atom of the nitramine group, followed by protonation and ionic dissociation. Then the oxodiazonium ion enters the intramolecular reaction with the neighboring tert-butyl-NNO-azoxy or phenyl group to form the corresponding heterocyclic systems.  相似文献   

14.
Treatment of 2-(tert-butyl-NNO-azoxy)anilines with phosgene at 20 °C was proposed as a novel route to 1,2,4-benzotriazin-3(4H )-one 1-oxides. This method involves a new reaction, viz., an intramolecular interaction of the tert-butyl-NNO-azoxy group with a C-electrophile (leading to the formation of the N(2)—C(3) bond of the triazine ring) followed by elimination of the tert-butyl group. Complete assignment of the signals in the 1H and 13C NMR spectra of the compounds obtained was performed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1507–1509, August, 2007.  相似文献   

15.
Reaction of zinc iodide, sodium azide and 2-[(3-dimethylaminopropylimino)methyl]-6-ethoxyphenol (HL) results in the formation of a trinuclear complex [Zn3L21,1-N3)2I2]. The complex is characterized by elemental analysis, IR spectroscopy, and X-ray crystallography. The complex possesses crystallographic two-fold rotation axis symmetry and crystallizes in the monoclinic system, C2/c space group, a = 23.241(2) Å, b = 10.849(1) Å, c = 17.384(2) Å, β = 120.868(1)°, V = 3762.4(6) Å3, Z = 4. The molecule consists of two [ZnL(N3)I] units connected together by a central Zn atom. The terminal Zn atom is fivecoordinated in a trigonal-bipyramidal geometry, and the central Zn atom is six-coordinated in an octahedral geometry. The Zn...Zn separation between the terminal and the central Zn atoms is 3.257(2) Å.  相似文献   

16.
The electrophilic substitution of thetert-butyl-NNO-azoxy group by the bromine atom was observed for the first time when 6-bromo-2,4-bis(tert-butyl-NNO-azoxy)-5-chloro-1,3-phenylenediamine was treated with bromine in AcOH. The structural factors promoting this reaction are discussed. The direction of the replacement was confirmed by PM3 calculations of the heats of formation of intermediate cationic σ-adducts. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2131–2134, November, 1999.  相似文献   

17.
A reaction of 1,1-bis(methoxy-NNO-azoxy)ethene with nitroform at ∼20 °C gave 1,1-bis-(methoxy-NNO-azoxy)-3,3,3-trinitropropane.  相似文献   

18.
The dependence of relative response factors on the carbon and chlorine atom number related to naphthalene has been investigated by using gas chromatography-mass spectrometry (GC-MS). The main goal of these investigations is to find some relationship between the GC-MS signal (peak area) and the test molecule chemical structure. By means of the knowledge of correlations of relative molar response, the quantitative analysis passes into easier and fewer reference materials are needed to investigate a sample having lot of component, because the sensitivities can be determined from the correlations studied in this paper. This is very important in daily analytical tasks, particularly for impurity profiling studies. Relative responses of some polychlorinated benzenes, polychlorinated biphenyls and n-alkylbenzenes are compared in the experiments. Linear correlation is found between the molecular structures of n-alkylbenzenes, i.e. the carbon atom number, and relative molar response. Relative molar responses of polychlorinated biphenyls also provided linear correlation taken as a function of chlorine atom number. Under given conditions, the increments of CH2 unit and chlorine atom number to the relative molar responses are 0.221 and 0.198, respectively. However, relative responses of polychlorinated benzenes showed diversity plotted against chlorine atom number, and their isomer compounds also gave various results according to the first ionization energy. The measurement conditions can influence the relative responses. The low injector temperature, the interface and the ion source temperature affected relative responses of high volatile compounds. However, when the parameters are kept under control, the results can become accurate and reproducible.  相似文献   

19.
Oxidation of one of the amino groups of 2-bromo-4,6-dichloro-1,3-phenylenediamine to the nitroso group followed by its conversion into thetert-butyl-NNO-azoxy group afforded a derivative ofm-(tert-butyl-NNO-azoxy)aniline,viz., 2-bromo-3-(tert-butyl-NNO-azoxyl)-4,6-dichloroaniline. Analogously, the second amino group was converted into thetert-butyl-NNO-azoxy group to form a derivative of 1,3-bis(tert-butyl-NNO-azoxy)benzene,viz., 3-bromo-2,4-bis(tert-butyl-NNO-azoxyl)-1,5-dichlorobenzene The reaction of the latter with ammonia yielded 2-amino- and 2,4-diamino-substituted 1,3-bis-(tert-butyl-NNO-azoxyl)benzenes. For Part 1, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2126–2130, November, 1999.  相似文献   

20.
The bis(allyl)nickel complex (η3-3-vinyl-2,4,5,6-tetraethyl-1-oxa-2,6-diboracyclohexenyl)(η3-2,3,4,5,6-pentaethyl-1-oxa-2,6-diboracyclohexenyl)nickel(IV) is formed by initial insertion of CO from Ni(CO)4 into the five-membered 1,3-diborolene I, to give a six-membered ring. Subsequent exchange of the CHCH3 group of I for the oxygen atom of the inserted CO and migration of a hydrogen atom from the
group of one ring to that of the other results in formation of the bis[1-oxa-2,6-diboracyclohexenyl]nickel, IV, having one vinyl and nine ethyl substituents. An X-ray structural analysis of IV shows the non-planarity of the C3B2O rings; the boron and oxygen atoms lie 0.4 and 0.7 Å, respectively, away from the best plane through the allyl carbon atoms. IV crystallizes in the space group P21/n with a = 9.065(2), b = 16.264(3), c = 10.187(2) Å, β = 104.28(1)°, and Z = 2.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号