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1.
The preparation of N-[1-(N,N,N,N-tetramethylphosphoramidoyl)-1H-benzimidazol-2-yl]-proponimidic ethyl ester 2 has been achieved by the reaction of N-(1H-benzimidazol-2-yl)-proponimidic acid ethyl ester 1 with N,N,N,N-tetramethylchlorophosphoramide. The structure of compound 2 has been determined by X-ray diffraction. The results of (1H, 13C, 31P) NMR, IR, EI-MS spectral data are consistent with those obtained from the X-ray diffraction. The compound crystallizes in the triclinic system, following the EsZ conformation. In the crystal, there are two weak C3–H3s1 and C15–H15sO1 intermolecular hydrogen bonds.  相似文献   

2.
The novel unsymmetrical extractant N,N′-dimethyl-N,N′-dioctylmalonamide (DMDOMA) was prepared by reaction of diethyl malonate with N-methyl octanamine. The extraction mechanism and the behavior of uranyl nitrate with DMDOMA employed cyclohexane as diluent were studied. The effects of concentrations of nitric acid, sodium nitrate, extractant and also the temperature on the extraction were considered. The stoichiometry of the extracted species is and the coordination of extracted species was suggested based on the IR data. The value of ΔH of extraction is -26.9 ± 0.80 kJ·mol-1. The value of the apparent extraction constant is 133.88 ± 17.92, which shows that the optimization of extractant structure improves the extractability of malonamide for uranyl nitrate.  相似文献   

3.
The hydrolysis mechanisms of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the density functional theory B3LYP/6-31+G(d, p) method. Two possible reaction pathways in the title reaction were considered. In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C-N single bond first (path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3LYP/6-31+G(d, p) level of theory based on the polarizable continuum model (CPCM). In water the first mechanism (path A) is also favored. Supported by the National Natural Science Foundation of China (Grant Nos. 20473055 and 20773089) and the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (Grant No. 20071108-18-15)  相似文献   

4.
溶剂萃取因反应速度快,分离效果好,已成为国内外分离提纯稀土的主要方法[1~3].在稀土元素的萃取分离中,为了提高萃取效率,从高放废液中分离、除去锕系和镧系元素从而实现选择性分离,首要问题是选择结构合适的萃取剂和萃取条件[4].由于酰胺类萃取剂具有螯合性能,对Ln(Ⅲ)、An(Ⅲ,Ⅳ,Ⅵ)和碱土金属都有良好的萃取能力,而且此类化合物耐辐射,不易水解,能够燃尽,不产生二次污染,是~种比较有发展前途的萃取剂,在核燃料后处理方面展示较好的应用前景[5~7].  相似文献   

5.
以煤油/辛醇(7:3,V/V)为稀释剂,研究N,N′-二甲基-N,N′-二辛基-3-氧戊二酰胺(DMDODGA)从盐酸介质中萃取三价镧系金属的性能及反应机理;考察了水相盐酸浓度、萃取剂浓度及温度对其萃取性能的影响。结果表明分配比在所研究酸度范围内随盐酸浓度的增加先增大后减小;随萃取剂浓度的增加而增大;萃合物的组成为MCl3.2DMDODGA(M=Sm,Gd,Dy)或MCl3.DMDODGA(M=Er,Lu)。萃取过程为放热反应,升高温度不利于萃取。同时计算出了萃取反应的平衡常数及热力学函数。萃合物的红外光谱表明羰基氧、醚氧均与镧系离子配位。  相似文献   

6.
Platinum(II) extraction by N,N′-dipentylethylenediamine-N′-thiocarbaldehyde from 0.1 M HCl into chloroform and toluene diluents was studied at 25°C and a phase contact time of 5 min. The extraction had a coordination mechanism with a Pt ← S bond formed in the extracted complex PtCl2S2. Concentration constants and thermodynamic parameters of the extraction reaction were calculated. Original Russian Text ? R.A. Khisamutdinov, Yu.I. Murinov, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 1, pp. 156–162.  相似文献   

7.
The title tetradecker complex C72H72Cl3K3N8Ni4O28 has been synthesized and structurally characterized. The four NiL (L = N, N-ethylene-bis(3-methoxysalicylideneiminate) segments were linked into a discrete tetradecker structure by three K+ cation coordinated to the phenolic oxygen atoms of the neighboring NiL units and the oxygen atom of the ClO4 anions acting as bridges. The two bicephalous K+ cations are nine-coordinated, while the middle one is involved in a distorted bipentagonal pyramid. For the Ni2+ ion, it is involved in a square planar coordination sphere formed by a N2O2 unit from the Schiff base ligand.  相似文献   

8.
Extraction of microamounts of europium and americium by a phenyltrifluoromethyl sulfone (FS 13) solution of hydrogen dicarbollylcobaltate (H+B) in the presence of N,N,N′,N′-tetraethyl-2,6-dipicolinamide (TEtDPA, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, \textHL 2 + , {\text{HL}}_{ 2}^{ + } , \textML23 + {\text{ML}_{2}^{3 +}} and \textML 3 3+ {\text{ML}_{ 3}^{ 3+}} (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in FS 13 saturated with water have been determined. It was found that the stability constants of the corresponding complexes \textEuLn 3+ {\text{EuL}}_{n}^{ 3+ } and \textAmLn 3+ {\text{AmL}}_{n}^{ 3+ }, where n = 2, 3 and L is TEtDPA, in the mentioned FS 13 medium are comparable.  相似文献   

9.
A high-yield straightforward conversion of lactams to lactim ethers is shown by the conversion of (10H)-dipyrrin-1-ones to (11H)-dipyrrin-1-ol methyl and ethyl ethers in 90% yield from heating in neat trimethyl or triethyl phosphite at 160°C. Unlike the parent dipyrrinones, which form intermolecularly hydrogen-bonded dimers in CHCl3, their lactim ethers are shown to be monomeric by vapor pressure osmometry. The latter react with boron trifluoride etherate to N,N′-bridged BF2 derivatives that exhibit strong fluorescence (φF 0.6–0.8) near 535 nm. X-Ray crystal structures were obtained of the lactim ethyl ether of kryptopyrromethenone and the BF2 derivative of the lactim ethyl ether 2,3-diethyl-7,8-dimethyl-(10H)-dipyrrin-1-one.  相似文献   

10.
The radiolytic stability of a branched diglycolamide extractant, namely N,N,N′,N′-tetra-2-ethylhexyl diglycolamide (T2EHDGA) dissolved in n-dodecane containing several phase modifiers, viz. N,N-dihexyloctanamide (DHOA), tri-n-butyl phosphate (TBP), 1-decanol and iso-decanol has been investigated. The distribution ratio of Am(III) decreased with increased radiation dose studied up to 1000 kGy. Nevertheless, all the composition of extractants showed satisfactory results up to 500 kGy, beyond which the extractants degraded drastically. The stripping behaviour of Am(III) with 0.2 M HNO3 was found to be unaffected even with the ligand solution irradiated up to 1000 kGy. Extraction of fission product and structural elements was also investigated using the irradiated solvents and was found to be not significantly affected with increasing absorbed dose with the exception of Mo which showed sharp rise in the distribution coefficient values. Loading of Nd in the organic phase decreased with the irradiated solvent due to degradation of the carrier. The effect of the absorbed dose on physical parameters such as density, viscosity and interfacial tension of the solvents has also been investigated.  相似文献   

11.
Extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B) in the presence of N,N,N′,N′-tetraisobutyl-2,6-dipicolinamide [T(iBu)DPA, L] has been investigated. The equilibrium data have been explained assuming that the species HL+, HL2 +, CaL2 2+, SrL2 2+ and SrL3 2+ are extracted into the organic phase. The values of extraction and stability constants of the cationic complexes in nitrobenzene saturated with water have been determined.  相似文献   

12.
A ligand, (N,N′-dibenzylethane-1,2-diamine) (L), and its complex with copper acetate was synthesized and characterized by some spectral analyses. The copper(Ⅱ) ion is six-coordinated and exhibites octahedral coordination geometry, the coordination atoms are four nitrogen atoms from two(L) ligands and two carboxyl oxygen atoms from two acetic acid groups, respectively. After studying the interaction of the complex with calf thymus DNA through UV and fluorescence spectra, we can find that there is a strong binding and a large affinity berween the complex and calf thymus DNA. CCDC: 649416.  相似文献   

13.
将吡啶-2,4,6-三羧酸(2,4,6-pytaH3),4-氨基-3,5-二(4-吡啶基)-1,2,4-三氮唑(4,4′-abpt)和CoCl2在不同的pH条件下发生水热反应,得到2个新的配位聚合物[Co(2,4,6-pytaH)(4,4′-abpt)(H2O)](1)和[Co1.5(2,4,6-pyta)(4,4′-abpt)(H2O)3].3.5H2O(2)。配合物1是在吡啶-2,4,6-三羧酸酸性环境下产生的,吡啶-2,4,6-三羧酸在水热条件下只脱去2个羧基上的质子变成2,4,6-pytaH2-,而配合物2是在NaOH碱性溶液下反应得到的,其中吡啶-2,4,6-三羧酸完全脱去3个羧基上的质子变成2,4,6-pyta3-。配合物1中包含一维Co-羧酸链,2中存在具有(4,4)拓扑网络的二维层。1和2中的一维链和二维层通过π-π堆积和丰富的氢键作用分别拓展成三维超分子网络。单晶结构分析表明,配合物1结晶于单斜晶系,P21/n空间群,a=0.961 30(10)nm,b=0.632 09(6)nm,c=3.372 9(4)nm,β=95.104(2)°,V=2.041 3(4)nm3,Z=4。而配合物2结晶于单斜晶系,P21/c空间群,a=1.795 2(2)nm,b=0.729 62(8)nm,c=2.078 7(2)nm,β=112.323(2)°,V=2.518 6(5)nm3,Z=4。  相似文献   

14.
A fluorescent red-shifted exciton-coupling chromophore, N,N′-carbonyl-bridged dipyrrinone, was subjected to fluorescence-detected CD (FDCD) measurements as a primitive structure-elucidating probe with trans-1,2-cyclohexanediol template in several solvents under various instrumental conditions. With the help of a JASCO ellipsoidal mirror device FDCD465, a chloroform solution achieved the sensitivity enhancement by 50 times of the transmission CD and 5 times of the conventional FDCD. All FDCD spectra were completely free from the polarization artifacts.  相似文献   

15.

Abstract  

An efficient and practical asymmetric synthesis of erythro-(1R,2S)-8-O-4′-neolignan myrislignan was achieved by using vanillin and pyrogallic acid as the starting materials. Two key steps are involved: preparation of an enantiopure threo alcohol of predictable stereochemistry by dihydroxylation with AD-mix-β, and inversion of the absolute configuration from the threo to the erythro isomer using a Mitsunobu reaction. The route illustrates a new methodology for the synthesis of erythro-8-O-4′-neolignan.  相似文献   

16.
Metal complexes derived from amides; N,N′-bis(2-thiophenecarboxamido)-1,3-diamino propane (1) and N,N′-bis(2-furancarboxamido)-1,3-diaminopropane (2) were characterized by elemental analysis, spectral (NMR, FT-IR, LC-MS) methods, magnetic moment, molar conductance, and TGA/DTA studies. The complexes were dimeric and have the general formula [ML.Clm.(H2O)n]2Cl2 where M=Cu(II), Zn(II), Co(III); m = 1, 2; n = 0, 1. The antimicrobial activities of the amides and their complexes were studied against the bacteria; Escherichia coli (ATCC 11230), Yersinia enterocolitica (ATCC 1501), Bacillus magaterium (RSKK 5117), Bacillus cereus (RSKK 863), Bacillus subtilis (RSKK 863) and yeast; Candida albicans (ATCC 10239).  相似文献   

17.
以3-吡啶醛和(1R,2R)-环己二胺进行缩合得到Schiff碱配体L1,然后,用配体L1和AgNO3进行配位反应,得到配合物[Ag(L1)(NO3)]n1),并用元素分析、FT-IR、X-射线单晶衍射、热重分析、粉末衍射对其进行了表征。晶体结构表明:配合物1属于单斜晶系,C2空间群,Ag(Ⅰ)的配位环境均为扭曲四面体,分别和硝酸根的氧原子,配体中的2个吡啶氮原子以及1个亚胺氮原子配位,配体L1有2种配位模式,其中,1个配体用两臂的2个吡啶氮原子分别和2个Ag(Ⅰ)离子配位,另外1个配体用两臂的2个吡啶氮原子分别和2个Ag(Ⅰ)离子配位,同时2个亚胺氮原子也分别和2个Ag(Ⅰ)离子配位,这样配合物形成3D孔状结构。同时研究了配合物的固体荧光性质。  相似文献   

18.
基于联萘衍生物手性构型高度稳定的特点, 以光学活性的(R)-2,2'-二乙炔基-1,1'-联萘为模板, 设计了3个有趣的拓扑环芳分子——含有4个手性联萘单元的(R,R,R,R)-2a2c, 并探讨了它们的合成. 合成路线涉及三甲基硅(Me3Si-)保护基的控制导入, 对位取代的芳基连接桥的链接, 保护基的脱去以及分子间偶合成环4个步骤. 用比旋光度([α]D), MS, IR, UV-Vis, 1H和13C NMR以及元素分析表征了这些化合物.  相似文献   

19.
采用B3LYP方法和6-311G(d, p)基组对CH3S及其氧化后继物CH3SO与Oy (y=1, 2, 3)反应形成酸雨的微观机理进行了理论研究. 对反应势能面上的各驻点进行几何构型全优化. 振动分析和IRC计算证实了中间体和过渡态的真实性和相互连接关系. 找到了7条生成SO2的反应途径, 其中CH3S与O直接反应得到产物CH3和SO最容易进行; CH3S先与O3反应, 其产物再与O3反应得到CH3SO2, CH3SO2最后分解得到CH3S和SO2较容易进行, 其它的反应较难进行.  相似文献   

20.
The rare earth-transition metal-indides RE 4IrIn (RE = Gd–Er) and the solid solutions RE 4 TIn1–x Mg x (RE = Y, Gd; T = Rh, Ir) were prepared by arc-melting of the elements and subsequent annealing. The rare earth sesquioxides were used as oxygen source for the suboxides RE 4IrInO0.25 (RE = Gd, Er). Single crystals of the indides were grown via slowly cooling of the samples and they were investigated via X-ray powder diffraction and single crystal diffractometer data: Gd4RhIn type, F 3m, a = 1372.3(6) pm for Gd4IrIn, a = 1365.3(6) pm for Tb4IrIn, a = 1356.7(4) pm for Dy4IrIn, a = 1353.9(4) pm for Ho4IrIn, a = 1344.1(4) pm for Er4IrIn, a = 1370.3(5) pm for Y4RhIn0.54Mg0.46, a = 1375.6(5) pm for Gd4IrIn0.55Mg0.45, a = 1373.0(3) pm for Gd4IrInO0.25, and a = 1345.1(4) pm for Er4IrInO0.25. The rhodium and iridium atoms have a trigonal prismatic rare earth coordination. Condensation of the RhRE 6 and IrRE 6 prisms leads to three-dimensional networks which leave voids that are filled by regular In4 or mixed In4–x Mg x tetrahedra. The indium (magnesium) atoms have twelve nearest neighbors (3In(Mg) + 9RE) in icosahedral coordination. The rare earth atoms build up a three-dimensional, adamantane-like network of condensed, edge and face-sharing octahedra. For Gd4IrInO0.25 and Er4IrInO0.25 the RE16 octahedra are filled with oxygen. The crystal chemical peculiarities of these rare earth rich compounds are discussed. Correspondence: Rainer P?ttgen, Institut für Anorganische und Analytische Chemie, Westf?lische Wilhelms-Universit?t Münster, Germany.  相似文献   

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