共查询到19条相似文献,搜索用时 62 毫秒
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四唑及其衍生物的理论研究:II.一氯代四唑负离子的从头算 总被引:1,自引:0,他引:1
用从头计算法,取6-31G基组,在MP2水平上,计算研究了1H-和2H-四唑一氯取代物三种负离子的全优化几何构型和电子结构,比较讨论了它们的芳香性和稳定性,发现三者均取平面构型,其芳香性和稳定性次序为5-氯四唑负离子〉2-氯四唑负离子〉1-氯四唑负离子,预示了形成金属配俣物时5-氯四唑作为配体的重要性和配位方式。 相似文献
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5-硝基-2H-四唑的合成、反应性及产物晶体结构的研究 总被引:1,自引:0,他引:1
5-氨基四唑(1)经过重氮化反应得到5-硝基四唑(5),5与甲醛反应得到2-羟甲基-5-硝基四唑(6),6与HCl或HBr反应分别得到5-5氯代四唑(7)和5-溴代四唑(8),采用MS,IR,1H NMR,13C NMR等技术对这些化合物进行了表征.用X射线单晶衍射法测定了化合物5-硝基四唑钠(4),5和6的晶体结构.化合物4属于三斜晶系,P-1空间群;化合物5和6均属于单斜晶系,P21空间群,化合物6的晶胞参数a=0.66131(18)nm,b=0.54905(15)nm,c=0.7566(2)nm,Z=2,V=0.27470(13)nm3,Dc=1.754g/cm3,F(000)=128,μ=0.160mm-1. 相似文献
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5-氨基四唑(1)经过重氮化反应得到5-硝基四唑(5), 5与甲醛反应得到2-羟甲基-5-硝基四唑(6), 6与HCl或HBr反应分别得到5-5氯代四唑(7)和5-溴代四唑(8), 采用MS, IR, 1H NMR, 13C NMR等技术对这些化合物进行了表征. 用X射线单晶衍射法测定了化合物5-硝基四唑钠(4), 5和6的晶体结构. 化合物4属于三斜晶系, P-1空间群; 化合物 5和6均属于单斜晶系, P21空间群, 化合物6的晶胞参数a=0.66131(18) nm, b=0.54905(15) nm, c=0.7566(2) nm, Z=2, V=0.27470(13) nm3, Dc=1.754 g/cm3, F(000)=128, μ=0.160 mm-1. 相似文献
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利用密度泛函理论研究了5-硝基-1-氢-四唑分子热分解的反应机理。首先用 B3LYP/6-31G(d)方法优化反应中反应物、过渡态、中间体以及产物的几何构型, 通过振动分析得到零点能校正值并确认反应的过渡态。此外,对各个构型作了 CCSD(T)/6-31G(d,p)水平下的单点计算。报道了三条可能的反应途径,即直接 开环途径和质子转移途径;其中N(1)-N(2)键断裂直接开环的机理与文献报道 一致;而涉及质子转移的反应途径则是一个新的发现;另一条关于N(4)-C(5) 键断裂直接开环的途径由于能垒较高,因此发生的几率较小。 相似文献
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多叠氮基三唑类高氮化合物的合成与晶体结构 总被引:4,自引:0,他引:4
2,5,2'-三氯-1,1'-偶氮-1,3,4-三唑(1)与叠氮化钠反应首次合成含有多叠氮和四氮烯(N—N=N—N)结构的高氮化合物2,5,2'-三叠氮-1,1'-偶氮-1,3,4-三唑(3). 在相同条件, 2,5,2',5'-四氯-1,1'-偶氮-1,3,4-三唑(2)与叠氮化钠反应没有得到2,5,2',5'-四叠氮-1,1'-偶氮-1,3,4-三唑(b), 而是得到其分解产物3,5-二叠氮基-1,2,4-三唑(4). 用X 射线单晶衍射测定了化合物3和4的晶体结构. 晶体2b通过分子间氢键的相互作用形成具有9元环的三聚体,并由于三唑环共轭体系使氮上的H原子具有酸性,从而导致互变现象发生. 相似文献
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制备得到标题化合物并对其进行了元素分析与红外光谱分析. 用X射线衍射方法测得其晶体结构属于正交晶系, 空间群Pbca, 晶胞参数a=0.6624(2) nm, b=1.7933(4) nm, c=2.3117(5) nm, V=2.7458(9) nm3, Z=4, Dc=1.849 g·cm-3. 其分子式可写作(ATZ)TNPG·2H2O. 5-氨基四唑阳离子(ATZ+)和三硝基间苯三酚阴离子(TNPG-)通过氢键在b轴和c轴方向上联成二维层面, 然后在a轴方向通过不同层中的水分子之间的氢键联接起来. 用差示扫描量热法(DSC), TG-DTG结合傅立叶变换红外光谱(FT-IR)分析了其热分解过程. 在氮气气氛下用10 ℃·min-1的升温速率测定发现,该化合物经历一个峰温为76 ℃的吸热过程及一个峰温为203 ℃的放热过程. 前者为脱除结晶水的过程, 后者为产物中的TNPG-与ATZ+的热分解过程, 放热的焓变为-212.10 kJ·mol-1. 对该过程估算动力学参数: 采用Kissinger法得活化能E=132.1 kJ·mol-1, ln (A/s-1)=12.54, r=0.9990; 采用Ozawa-Doyle法得E=133.1 kJ·mol-1, r=0.9992. 相似文献
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Moritz Kofen Marcus Lommel Dr. Maximilian H. H. Wurzenberger Prof. Dr. Thomas M. Klapötke Dr. Jörg Stierstorfer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(38):e202200492
Highly energetic 1-(azidomethyl)-5H-tetrazole (AzMT, 3 ) has been synthesized and characterized. This completes the series of 1-(azidoalkyl)-5H-tetrazoles represented by 1-(azidoethyl)-5H-tetrazole (AET) and 1-(azidopropyl)-5H-tetrazole (APT). AzMT was thoroughly analyzed by single-crystal X-ray diffraction experiments, elemental analysis, IR spectroscopy and multinuclear (1H, 13C, 14N, 15N) NMR measurements. Several energetic coordination compounds (ECCs) of 3d metals (Mn, Fe, Cu, Zn) and silver in combination with anions such as (per)chlorate, mono- and dihydroxy-trinitrophenolate were prepared, giving insight into the coordination behavior of AzMT as a ligand. The synthesized ECCs were also analyzed by X-ray diffraction experiments, elemental analysis, and IR spectroscopy. Differential thermal analysis for all compounds was conducted, and the sensitivity towards external stimuli (impact, friction, and ESD) was measured. Due to the high enthalpy of formation of AzMT (+654.5 kJ mol−1), some of the resulting coordination compounds are extremely sensitive, yet are able to undergo deflagration-to-detonation transition (DDT) and initiate pentaerythritol tetranitrate (PETN). Therefore, they are to be ranked as primary explosives. 相似文献
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Dan Chen Prof. Hongwei Yang Zhenxin Yi Hualin Xiong Lin Zhang Shunguan Zhu Prof. Guangbin Cheng 《Angewandte Chemie (International ed. in English)》2018,57(8):2081-2084
The synthesis and characterization of the metal‐free polyazido compounds 3,6‐bis‐(2‐(4,6‐diazido‐1,3,5‐triazin‐2‐yl)‐hydrazinyl)‐1,2,4,5‐tetrazine ( 2 ) and 3,6‐bis‐(2‐(4,6‐diazido‐1,3,5‐triazin‐2‐yl)‐diazenyl)‐1,2,4,5‐tetrazine ( 4 ) are presented. Two compounds were characterized by NMR spectra, IR spectroscopy, mass spectrometry, and differential scanning calorimetry (DSC). Additionally, the structure of 2 was confirmed by single‐crystal X‐ray diffraction. Compounds 2 and 4 exhibit measured densities (1.755 g cm?3 and 1.763 g cm?3), good thermal stabilities (194 °C and 189 °C), high heat of formation (2114 kJ mol?1 and 2820 kJ mol?1), and excellent detonation performance (D, 8365 m s?1 and 8602 m s?1; P, 26.8 GPa and 29.4 GPa). Furthermore, compounds 2 and 4 have been tested for their priming ability to detonate RDX. The results indicate that the title compound 2 is a potential environmentally friendly alternative candidate to lead‐based primary explosives. 相似文献
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建立了反相键合相液相色谱分析离子液体咪唑类离子液体[bmim]PF6[、bmim]BF4、吡啶类离子液体[bupy]BF4的纯度及其中高沸点有机物的方法.以缓冲溶液控制流动相pH值,显著改善了峰形.保留时间定性,外标法定量. 相似文献
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应用高速逆流色谱法对同分异构体的分离纯化进行研究。实验结果表明,以正己烷-乙酸乙酯-水(体积比为1∶10∶10)为两相溶剂系统,上相为固定相,下相为流动相,进行二次高速逆流色谱分离,可从茶多酚中分离出g级的儿茶素同分异构体——(-)-表没食子儿茶素没食子酸酯(EGCG)和(-)-没食子儿茶素没食子酸酯(GCG),其高效液相色谱纯度均在98%以上。选择四氯化碳-氯仿-甲醇-水(体积比为7∶3∶7∶3)为溶剂系统,下相为固定相,上相为流动相,经一次高速逆流色谱即可将药物中间体溴代苯胺同分异构体进行有效的分离。 相似文献
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Takashi Abe Dr. Young‐Hyuk Joo Dr. Guo‐Hong Tao Dr. Brendan Twamley Dr. Jean'ne M. Shreeve Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(16):4102-4110
Base‐catalyzed activation of the C? F bond in the trifluoromethylazo‐substituted cyclic and acyclic alkanes provides a route to disubstituted azidotetrazoles. For example, the reaction of 1,2‐bis(trifluoromethylazo)ethane with four equivalents of NaN3 gave the alkyl‐bridged bis(5‐azido‐1H‐tetrazol‐1‐yl)‐1,2‐dimine, N,N′‐bis(5‐azido‐1H‐tetrazol‐1‐yl)‐1,2‐diiminoethane, in 75 % yield (see scheme).
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《Analytical letters》2012,45(11):869-885
Abstract High pressure liquid chromatography was used to separate and determine quantitatively the following groups of sulfur compounds: thiols, sulfides, disulfides, sulfones, isothiocyanates, thioamides, and thioureas. Amperometric and UV detectors were compared; for thiols, thioureas, isothiocyanates, and thioamides, the former was generally more sensitive. With the exception of alkyl and cycloalkyl sulfides, the liquid chromatographic method can be used for the analysis of the investigated sulfur compounds below the ppm range. The method developed was compared to gas chromatography with flame photometric detection. The latter was found to be superior for the analysis of alkyl and cycloalkyl thiols, sulfides and disulfides of molecular weight below 200, whereas the former was more suitable for the analysis of aromatic thiols, sulfides and disulfides, as well as thioamides, isothiocyanates, and thioureas. Both methods were equivalent for the analysis of aromatic sulfones. 相似文献
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