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51.
A. Yu. Ershov 《Chemistry of Heterocyclic Compounds》2002,38(6):730-737
We have studied the reaction of 5-hydroxy-3,3,5-trimethylisoxazolidine and 5-hydroxy-3,5-dimethyl-2-isoxazoline with derivatives of thiosemicarbazide and also thiocarbonohydrazine. Both reactions serve as a method for synthesis of the previously unknown 5-thiosemicarbazido(thiocarbonohydrazino)isoxazolidines and -2-isoxazolines. 1H and 13C NMR spectroscopy revealed a tendency of the indicated compounds toward ring-chain and ring-ring tautomeric conversions in solutions involving the 1,2,4-triazolidine, 2-pyrazoline, and 1,2,4,5-tetrazine rings. 相似文献
52.
The synthesis of high-nitrogen energetic material 3,3′-azobis (6-amino-1,2,4,5-tetrazine) (DAAT) from 3,6-bis (3,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazine
by a four-step reaction is described. The thermal properties of DAAT were investigated by using Differential scanning calorimetry
(DSC), Pressure differential scanning calorimetry (PDSC) and Thermogravimetry (TG) techniques. Kinetic parameters of decomposition
and mechanism functions were obtained. The results showed that DAAT is thermally stable up to 283°C and gives an exotherm
maximum at 320°C with ΔH of 1974.33 J·g−1, which is higher than HMX. The values of E
a are 209.69 and 208.77 kJ·mol−1 by the methods of Kissinger and Ozawa, respectively. The decomposition rate of DAAT is sensitive to pressure and in direct
proportion to atmosphere pressure. The explosive performances of DAAT were calculated theoretically by VLW equation-of-state
(EOS) and the results showed that several explosive formulations based on DAAT have high-energy and insensitive performance.
Translated from Huaxue Tongbao (Chemistry), 2006, 69(9): 685–689 (in Chinese) 相似文献
53.
A. O. Terent"ev A. V. Kutkin M. M. Platonov I. I. Vorontsov M. Yu. Antipin Yu. N. Ogibin G. I. Nikishin 《Russian Chemical Bulletin》2004,53(3):681-687
Aliphatic and alicyclic gem-bis-hydroperoxides and their derivatives, bis(1-hydroperoxycycloalkyl) and bis(1-hydroperoxyalkyl) peroxides, dispiro- and tetraalkyl-1,2,4,5-tetroxanes were synthesized by the reaction of aliphatic and alicyclic acetals and enol ethers with H2O2 in the presence of BF3 in anhydrous Et2O. 相似文献
54.
Saikat Das Sharma 《Tetrahedron letters》2008,49(14):2216-2220
InCl3·3H2O was found to be a mild and effective catalyst for the efficient, one-pot, three component synthesis of 2,4,5-trisubstituted imidazoles at room temperature. Moreover, the utility of this protocol was further explored conveniently for the one-pot, four component synthesis of 1,2,4,5-tetrasubstituted imidazoles in high yields. 相似文献
55.
《Journal of Coordination Chemistry》2012,65(12):2051-2064
Two energetic strontium(II) complexes with nitrogen-rich 3,6-bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine (BTATz) were synthesized. The metal complexes were characterized by IR, elemental analysis, and single-crystal X-ray diffraction. DSC and TG-DTG were used to study the thermal behavior, non-isothermal decomposition reaction kinetics, self-accelerating decomposition temperature (T SADT), thermal ignition temperature (T TIT), critical temperature of thermal explosion (T b), and the adiabatic time-to-explosion (t TIad). The data indicate competitive energetic materials. 相似文献
56.
以乙腈和芳基腈为原料, 经过醚化、环化和还原三步方便且有效地合成了3-芳基-6-甲基-1,6-二氢-1,2,4,5-四嗪, 并在此基础上合成了一系列新的3-芳基-6-甲基-1,6-二氢-1,2,4,5-四嗪衍生物, 通过元素分析, 1H NMR, IR和HRMS对这些化合物进行了表征. 对化合物N-邻甲基苯-3-苯基-6-甲基-1,6-二氢-1,2,4,5-四嗪-1-甲酰胺(5a)的X射线晶体衍射研究表明: 其属于单斜晶系, P21 /c空间群, 晶胞参数a=1.3941(6) nm, b=0.5675(2) nm, c=2.0614(8) nm; α=γ=90°, β=102.055(6)°; V=1.5949(11) nm3, 此类化合物的四嗪环采用不对称船式结构, 且具有同芳香性. 相似文献
57.
A novel heterometallic complex,[Zn4Ni(OH)2(btec)2(titb)2(H2O)2]·2H2O(1)(H4btec=1,2,4,5-benzenetetracarboxylic acid,titb=1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trime-thylbenzene),has been hydrothermally prepared and characterized by IR spectroscopy,elemental analysis and single-crystal X-ray diffraction.The crystal is of triclinic system,space group P1 with a=10.817(10),b=11.878(11),c=14.569(14),α=71.762(12),β=76.122(13),γ=71.493(13)°,V=1665(3)3,C62H62N12O22Zn4Ni,Mr=1647.43,Dc=1.643 g/cm3,F(000)=842,μ=1.784 mm-1 and Z=1.The final R=0.0531 and wR=0.0890 for 3545 observed reflections(Ⅰ 2σ(Ⅰ)).In the title complex,the btec ligand acts as a five-dentate bridging ligand to link up zinc and nickel atoms into a lamellar framework,which are further interlinked into a 3-D framework via the titb ligands. 相似文献
58.
59.
V. N. Yarovenko A. A. Es'kov I. V. Zavarzin E. I. Chernoburova A. Yu. Martynkin M. M. Krayuskin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1283-1288
Monothioxamides unsubstituted at the thioamidic nitrogen atom were obtained by the reaction of NS-morpholino-NO-R-thioxamides with ammonia. Carbamoyl-containing 5-phenylcarbamoyl-1,2,4-dithiazoles, 6-phenylcarbamoyl-5,6-dihydro-[1,2,4,5]-dithiadiazin-3-one, and 5-phenylcarbamoyl-2-oxy-1,3,4-thiadiazole were synthesized by the reaction of monothioxamides or thiohydrazides of oxamic acids with chlorocarbonylsulfenyl chloride. 相似文献
60.
选择刚性的1,2,4,5-均苯四甲酸(H4L)为主配体,以1,3-双(1H-咪唑-1-基甲基)苯(1,3-bib)为辅助配体,在水热条件下,与过渡金属离子Cd2+配位合成了配合物[Cd(L)0.5(1,3-bib)(H2O)]·H2O(1)。利用元素分析、红外光谱、X射线单晶衍射、热重和X射线粉末衍射对其结构进行了表征,并研究了化合物的荧光性质。结果表明:配合物1属正交晶系,空间群Pbca,a=0.857 08(4)nm,b=1.912 23(10)nm,c=2.451 60(12)nm。配合物1中Cd2+与L4-配体的羧基通过双齿螯合配位,通过1,3-bib连接形成三维网状结构。配合物1具有较强的荧光,其对丙酮溶剂、MnO4-、Hg2+离子有一定的荧光猝灭。 相似文献