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1.
Jian-Hua Yi Feng-Qi Zhao Ying-Hui Ren Si-Yu Xu Hai-Xia Ma Rong-Zu Hu 《Journal of Thermal Analysis and Calorimetry》2010,100(2):623-627
The thermal decomposition mechanism of hydrazine 3-nitro-1,2,4-triazol-5-one (HNTO) compound was studied by means of differential
scanning calorimetry (DSC), thermogravimetry and derivative thermogravimetry (TG-DTG), and the coupled simultaneous techniques
of in situ thermolysis cell with rapid scan Fourier transform infrared spectroscopy (in situ thermolysis/RSFTIR). The thermal
decomposition mechanism is proposed. The quantum chemical calculation on HNTO was carried out at B3LYP level with 6-31G+(d)
basis set. The results show that HNTO has two exothermic decomposition reaction stages: nitryl group break first away from
HNTO molecule, then hydrazine group break almost simultaneously away with carbonyl group, accompanying azole ring breaking
in the first stage, and the reciprocity of fragments generated from the decomposition reaction is appeared in the second one.
The C–N bond strength sequence in the pentabasic ring (shown in Scheme 1) can be obtained from the quantum chemical calculation as: C3–N4 > N2–C3 > N4–C5 > N1–C5. The weakest bond in NTO− is N7–C3. N11–N4 bond strength is almost equal to N4–C5. The theoretic calculation is in agreement with that of the thermal
decomposition experiment.
相似文献
2.
Yu. V. Shurukhin A. V. Dovgilevich I. I. Grandberg B. P. Baskunov 《Chemistry of Heterocyclic Compounds》1988,24(7):760-764
In agreement with the thermolysis characteristics of 1,5-disubstituted tetrazoles, the fragmentation pattern of 1-(o-, m-, and p-tolyl)-5-phenyltetrazoles has been shown to consist of a sequence of reactions, namely, initial tautomeric conversion to an azide structure, followed by elimination of a molecule of nitrogen, and rearrangement of the resulting nitrene intermediate to a cation-radical derivative of a methyl-substituted 2-phenylbenzimidazole compound. In the case of 1-(o-tolyl)-5-phenyltetrazole an alternative pathway is observed, involving cyclization of the nitrene intermediate at the methyl group (an insertion reaction into a C-H bond) to form dihydroquinazoline derivatives. An analogous cyclization process has been noted for the thermolysis process as well.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 925–930, July, 1988. 相似文献
3.
V. N. Drozd V. N. Knyazev F. M. Stoyanovich F. M. Dolgushin A. I. Yanovsky 《Russian Chemical Bulletin》1997,46(1):113-121
The interaction of stable 2-RSO2-benzonitrile oxides1a−c (R=Ph, But, or PhMeN) with C60 fullerene proceeds at the double (6,6)-bond of fullerene as the [3+2] cycloaddition to form the corresponding isoxazolines2a−c. The molecular structure of compound2b was established by X-ray structural analysis. The interaction of C60 fullerene with 2-(5-methyl-4-nitrothiophene)carbonitrile sulfide, which was obtained by thermolysis of 5-(5′-methyl-4′-nitro-2′-thienyl)1,3,4-oxathiazol-2-one,
affords only unstable products.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 118–126, January, 1997. 相似文献
4.
R. E. Trifonov G. V. Gurskaya A. V. Gaenko V. E. Zavodnik V. A. Ostrovskii 《Chemistry of Heterocyclic Compounds》2007,43(3):320-325
The interaction of 5-phenyltetrazolate anion with chloroform in strongly alkaline medium leads to the formation of tris(5-phenyltetrazol-1-yl)methane
and 2-dichloromethyl-5-phenyltetrazole. The structures of tris(5-phenyltetrazol-1-yl)-methane and of its isomer tris(5-phenyltetrazol-2-yl)methane
have been investigated by X-ray structural analysis and theoretical calculations carried out on the B3LYP/6-31G** basis.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 398–404, March, 2007. 相似文献
5.
Marty W. DeGroot Chhatra Khadka Harald Rösner John F. Corrigan 《Journal of Cluster Science》2006,17(1):97-110
The thermolysis of the zinc trimethylsilylchalcogenolate complexes (N,N′-tmeda)Zn(ESiMe3)2 (E = S, 1; E = Se, 2) and (3,5-Me2-C5H3N)2Zn(ESiMe3)2 (E = S, 3; E = Se, 4) has been investigated. Solid-state thermal decomposition of complexes 1–4 above 250°C results in the formation of hexagonal ZnS and cubic ZnSe, respectively, via the liberation of TMEDA (1–2) or 3,5-lutidine (3–4) and E(SiMe3)2. Solid-state or solution thermolysis of these complexes up to 200°C produces nanocrystalline ZnS and ZnSe materials whose surface is protected by either coordinated TMEDA or 3,5-lutidine ligands. The progress of the step-wise solid-state decomposition of these complexes was monitored by thermogravimetric and single differential thermal analysis and volatile decomposition products in both solution and solid-state experiments were identified by GC/MS.Dedicated to Professor Brian F. G. Johnson on the occasion of his retirement. 相似文献
6.
We have found that the thermolysis of 5-substituted-2-acyl-tetrazoles (I) at 60–110° leads to quantitative loss of nitrogen and formation of an N-acyl-nitrilimine (III) as a hypothetical intermediate. This immediately reacts via ring closure to form 1,3,4-oxadiazoles (IV) in excellent yields. By an elegant reaction series it is possible to form polyaryles with alternating phenyl and 1,3,4-oxadiazole rings by repeated reaction of 5-phenyltetrazole with p-cyano-benzoylchloride followed by treatment with lithium azide. Starting with terephthalonitrile polyaryles possessing 9 rings were synthesized in 4 steps. The ultra-violet absorption of the 2,5-disubstituted 1,3,4-oxadiazole systems resembles very closely the absorption curve of a p-disubstituted phenyl-group. 相似文献
7.
Thermal and Spectroscopic Studies on the Decomposition of Some Aminoguanidine Nitrates 总被引:1,自引:0,他引:1
S. R. Naidu K. V. Prabhakaran N. M. Bhide E. M. Kurian 《Journal of Thermal Analysis and Calorimetry》2000,61(3):861-871
Diaminoguanidine nitrate (DAGN) and triaminoguanidine nitrate (TAGN),potential energetic materials in emerging propulsion
technology with high mass impetus at low isochoric flame temperature have been studied as regards kinetics and mechanism of
thermal decomposition using thermogravimetry (TG), differential thermal analysis (DTA),infrared spectroscopy (IR) and hot
stage microscopy. Kinetics of thermolysis has been followed by isothermal TG and IR. For the initial stage of thermolysis
of DAGN the best linearity with a correlation coefficient of 0.9976 was obtained for the Avrami-Erofe'evequation, n=2, by isothermal TG. The activation energy was found to be 130 kJ mol–1 and logA=11.4. The initial stage of thermolysis of TAGN also obeyed the Avrami-Erofe'ev equation, n=2, with a correlation coefficient of 0.9975by isothermal TG and the kinetic parameters are E=160.0 kJ mol–1 and logA=16.0. High temperature IR spectra showed exquisite preferential loss in intensity of the NH2, NH, N–N stretching and CNN bending. Spectroscopic and other results favour deamination reaction involving the rupture of
the N–N bond as the primary step in the thermal decomposition.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
A. S. Rozenberg E. I. Aleksandrova G. I. Dzhardimalieva A. N. Titkov A. D. Pomogailo 《Russian Chemical Bulletin》1993,42(10):1666-1672
The thermal decomposition of iron (III) acrylate, [Fe3O(CH2=CHCOO)6 · 3H2O]OH (FeAcr), a monomer with a complex cluster cation, has been studied at 200–370 °C. Thermal transformations of FeAcr occur
in two temperature regions. The rates of gas evolution in the low temperature region (200–300 °C) and the high temperature
region (300–370 °C) are described by first-order equations withk=4.2 · 1021exp[−59000/(RT)] s−1 andk=1.3 · 106exp[−30500/(RT)] s−1, respectively. A study of the qualitative and quantitative composition of the products of FeAcr thermolysis was carried out.
The thermal transformation of FeAcr is a complex process of dehydration, degradation, and polymerization in the solid phase
followed by decarboxylation of the metal-carboxyl groups of the polymer.
for part 33 see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1743–1750, October, 1993. 相似文献
9.
B. L. Korsounskii V. V. Nedel'ko N. V. Chukanov T. S. Larikova F. Volk 《Russian Chemical Bulletin》2000,49(5):812-818
Thermal decomposition of hexanitrohexaazaisowurtzitane (HNIW) in the solid state and in solution was studied by thermogravimetry,
manometry, optical microscopy, and IR spectroscopy. The kinetics of the reaction in the solid state is described by the first-order
equation of autocatalysis. The rate constants and activation parameters of HNIW thermal decomposition in the solid state and
solution were determined. The content of N2 amounts to approximately half of the gaseous products of HNIW thermolysis. The thermolysis of HNIW and its burning are accompanied
by the formation of a condensed residue. During these processes, five of six nitro groups of the HNIW molecule are removed,
and one NO2 group remains in the residue, which contains amino groups and no C−H bonds.
Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 815–821, May, 2000. 相似文献
10.
V. V. Nedel'ko A. V. Shastin B. L. Korsunskii N. V. Chukanov T. S. Larikova A. I. Kazakov 《Russian Chemical Bulletin》2005,54(7):1710-1714
Ditetrazol-5-ylamine (DTA) was synthesized from cyanuric chloride in four steps. The thermal decomposition of DTA in the solid
state was studied by thermogravimetry, volumetry, mass spectrometry, IR spectroscopy, and calorimetry. Under isothermal conditions
at 200–242 °C, thermal decomposition obeys the first order autocatalytic kinetics. The kinetic and activation parameters of
DTA decomposition were determined. The composition of gaseous reaction products and the structure of condensed residue were
studied. The thermal effect of thermal DTA decomposition is 281.4 kJ mol−1. The nitrogen content in a mixture of gaseous products formed by the reaction in a temperature interval of 200–242 °C exceeds
97 vol.%.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1660–1664, July, 2005. 相似文献
11.
The thermal opening of the diaziridine ring in 1-methyl-and 1,3,3-trimethyl-1,3,4,8b-tetra-hydro[1,2]diazirino[3,1-a]isoquinolines
in the presence of N-arylmaleimides leads to the predominant or exclusive formation of the trans isomers of the products of
1,3-dipolar cycloaddition. In the absence of dipolarophile, the conversion of the starting diaziridines is incomplete over
the same time period, while the thermolysis products are N-[3,4-dihydro-2(1H)-isoquinolyl]-and N-[3,3-dimethyl-3,4-di-hydro-2(1H)-isoquinolyl]-N-methyleneamines
formed as the result of isomerization of intermediate labile azomethineimines.
Dedicated to the memory of A. A. Potekhin.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1071–1079, July, 2008. 相似文献
12.
A. T. Shuvaev A. S. Rozenberg G. I. Dzhardimalieva N. P. Ivleva V. G. Vlasenko T. I. Nedoseikina T. A. Lyubeznova I. E. Uflyand A. D. Pomogailo 《Russian Chemical Bulletin》1998,47(8):1460-1465
Thermal transformations of FeIII maleate, [Fe3O(OOCCH=CHCOOH)6]OH·3H2O (1), in an autogenerated atmosphere and the change in the short-range surrounding of Fe atoms during thermolysis were studied.
The thermal transformations of1 are accompanied by the following processes: dehydration with simultaneous rearrangement of the ligand environment and formation
of maleic acid, and polymerization of the rearranged monomer and its decarboxylation at high temperatures. In the initial
stage of decarboxylation, the destruction of the metal-carboxylate Fe3O complex occurs followed by the formation of the Fe−Fe bond (r=0.246 nm). The oxidation of the Fe atoms is observed when the thermolysis duration increases.
For Part 49, seeIzv. Akad. Nauk, Ser. Khim., 1998; 1145 [Russ. Chem. Bull., 1998,47, 1113 (Engl. Transl.)].
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1505–1510, August, 1998. 相似文献
13.
S. Devaraju M. R. Vengatesan A. Ashok Kumar M. Alagar 《Journal of Sol-Gel Science and Technology》2011,60(1):33-40
New type of Polybenzoxazine–silica (PBZ–SiO2) hybrid nanocomposites was prepared through in situ sol–gel method. Benzoxazine was synthesized using bisphenol-A, trans-4-aminocyclohexanol hydrochloride and formaldehyde solution through Mannich condensation reaction and was characterized by
FT-IR, 1HNMR and 13CNMR spectroscopy. The methodology adopted in the present study involves to formation of hydrogen bond interaction between
the benzoxazine monomer and the silica matrix, followed by the ring opening polymerization of benzoxazine monomer through
thermal curing to obtain a red brown transparent PBZ–SiO2 hybrid. The formation of hybrid nanocomposites was confirmed by FT-IR. Thermal and morphological properties of the hybrid
materials were investigated by the differential scanning calorimetry (DSC), thermo gravimetric analysis (TGA), scanning electron
microscopy (SEM). The PBZ–SiO2 hybrids show improved thermal properties and glass transition (Tg) temperature. The nitrogen porosimetry study was carried
out to confirm the nanometer level integration of polybenzoxazine in the PBZ–SiO2 hybrid nanocomposites. 相似文献
14.
Thongthai Witoon Metta Chareonpanich Jumras Limtrakul 《Journal of Sol-Gel Science and Technology》2009,51(2):146-152
In this study, the formation of silica–chitosan hybrid materials via sol–gel process under pH values of 2–6 were investigated
using N2 sorption analysis, scanning electron microscopy, transmission electron microscopy, thermal analysis and zeta potential analyzer.
The hierarchical structure consisting of meso- and macropore was formed when pH value was higher than 2. Mesopores were formed
as the interparticle channels of silica nanoparticles aggregates, whereas macropores were the void between the aggregates
(clusters). The clusters size was decreased with increasing the pH value, resulting in the increase of the macroporosity.
The thermal conductivity of the products was controlled in the range of 0.06 and 0.13 W m−1 K−1 by varying the product porosity between 88 and 69% (pH 6 and pH 2, respectively). 相似文献
15.
N. A. Nedolya O. A. Tarasova O. G. Volostnykh A. I. Albanov B. A. Trofimov 《Chemistry of Heterocyclic Compounds》2012,47(11):1430-1435
For the case of 1-(allylsulfanyl)-2-methoxy-N-(1-methylethylidene)buta-1,3-dien-1-amine, obtained from α-lithiated methoxyallene, isopropyl isothiocyanate, and allyl bromide,
it was shown that 5-ethylidene-2-(1-methoxyprop-2-enyl)-4,4-dimethyl-4,5-dihydro-1,3-thiazole and 6-methoxy-2-methyl-3H-azepine
are formed competitively upon the action of the t-BuOK–THF–DMSO system. 相似文献
16.
A new conjugated polymer with semiconducting characteristics-polyaminothiazole-was obtained by oxidative polymerization of
2-aminothiazole in the presence of iron(III) chloride. A reaction scheme is proposed on the basis of the data from IR, ESR,
and electronic spectroscopy. It involves the formation of an intermediate aminothiazole-FeCl3 complex with coordination of the initiator at the nitrogen atom and subsequent oxidation of another molecule of aminothiazole
by this complex with the formation of a radical-cation, leading to polymerization.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 2, pp. 91–95, March–April, 2007. 相似文献
17.
Syntheses Based on Natural α-Amino Acids. Cyanoethylation of 3-Substituted 5-Methyl-2-thiohydantoins
Starting from α-alanine, the C- and S-cyanoethyl derivatives of 5-methyl-3-phenyl(allyl)-2-thiohydantoins have been synthesized.
It was shown that the products of hydrolysis of C-cyanoethyl derivatives, 5-methyl-3-phenyl(allyl)-(β-carboxyethyl)-2-thiohydantoins,
are formed in addition.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1657–1661, November, 2005. 相似文献
18.
The basic kinetic parameters of thermal polymerization of hexafluoropropylene, namely, general rate constants, degree of polymerization,
and their temperature and pressure dependences in the range of 230–290 °C and 2–12 kbar (200–1200 MPa) were determined. The
activation energy (E
act = 132±4 kJ mol−1) and activation volume (ΔV
0
≠ = −27±1 cm3 mol−1) were calculated. The activation energy of thermal initiation of polymerization was estimated. The reaction scheme based
on the assumption about a biradical mechanism of polymerization initiation was proposed. 相似文献
19.
The thermolysis of 5-diazo-6-methoxy-1-methyl-1,6-dihydrouracil ( 1 ) has afforded methyl N-(1-methyl-1,2,3-triazol-4-oyl)carbamate ( 2 ), bis-(1-methyl-1,2,3-triazol-4-oyl)amine ( 3 ) and di-methylcarbimate ( 4 ). The reaction was shown to proceed with the initial formation of 2 followed by a subsequent disproportionation of 2 to give 3 and 4 . A similar thermolysis of 5-diazo-6-ethoxy-1-methyl-1,6-dihydrouracil ( 9 ) gave ethyl N-(1-methyl-1,2,3-triazol-4-oyl)car-bamate ( 10 ) as the sole product. Double labeling experiments have indicated that a major pathway for these reactions involves an intermolecular transfer of the C-6 substituent to the C-2 position. 相似文献
20.
N. A. Nedolya O. A. Tarasova O. G. Volostnykh A. I. Albanov 《Chemistry of Heterocyclic Compounds》2008,44(9):1113-1116
The first representative of thienyl-substituted 3H-azepines has been synthesized starting from dilithiated 2-methyl-5-propargylthiophene
and isopropyl isothiocyanate. It was shown that N-(1-methylethylidene)-2-(5-methyl-2-thienyl)-1-(methylthio)-1,3-butadiene-1-amine
(2-aza-1,3,5-triene) formed as a result of this reaction is readily converted into 2-methyl-6-(5-methyl-2-thienyl)-3H-azepine
under the action of super bases.
Dedicated to Academician B. A. Trofimov of the Russian Academy of Sciences on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1380–1383, September, 2008. 相似文献