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The extraction behavior of N,N′-diethyl-N,N′-dibenzenyl-urea (DEDBU) to Uranium(Ⅵ) and Thorium(Ⅳ) from nitric acid solution was studied by using xylene as diluent. The effects of aqueous HNO3 concentration and ex-tractant concentration on the extraction distribution ratio of U(Ⅵ) and Th(Ⅳ) were studied, and the results show that the extraction behavior of the extractant to U(Ⅵ) is similar to tributyl phosphate (TBP), the solvation numbers for DEDBU and TBP are two, respectively. Under the experiment condition, the extractant does not show the extraction behavior to Th(Ⅳ), this result exhibits that the extractant has good application to separate U(Ⅵ) and Th(Ⅳ). The crystal structure of the complex UO2(NO3)2[CH2(CH2)2CONC8H17]2 was determined by single crystal X-ray diffraction. Crystal data: C24H46N4O10U, triclinic, space group , a = 8.662(2)?, b= 10.07(2)?, c= 10.895(3)?, α = 103.77(2)°, β = 92.01(2)°, γ = 96.23(2)°, V= 915.7(4)?3, Mr = 934.78, Z= 1, Dc= 1.695 g·cm-3, F(000) = 462, μ = 4.495mm-1, R= 0.0250, wR= 0.0591, observed reflec-tions 3566 (I>2σ(I)).The central uranyl ions is coordinated by six oxygen atoms, two of them are from the carbonyl groups of N,N′-diethyl-N,N′-dibenzenyl-urea molecules, and the other four are from two nitrate groups. 相似文献
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Xu Feng Chen Yong-Mei Yang Shi-Yan Sun Wen-Hua Yu Kai-Bei 《Transition Metal Chemistry》2000,25(1):108-111
CpMoFeCo(CO)7(3-S) reacts with Cp*M(CO)3Cl or CpM(CO)3Cl (M=W, Mo) to gave the mixed-metal clusters Cp*WCpMoFe(CO)7(3-S) (1), Cp*MoCpMoFe(CO)7(3-S) (2), CpWCp*MoFe(CO)7(3-S) (3), CpMoCp*MoFe(CO)7(3-S) (4) and Cp*WCp*MoFe(CO)7(3-S) (5). The title clusters have been characterized by i.r., 1H/13C-n.m.r. spectroscopy and their compositions have been confirmed by elemental analyses. The X-ray crystal structure analysis shows the two independent enantiomeric molecules of clusters (1) in one crystal structure unit. 相似文献
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[K(HTNR)(H_2O)]_n的制备、晶体结构和热分解机理 总被引:3,自引:0,他引:3
通过2,4,6-三硝基间苯二酚(斯蒂芬酸,TNR)与氢氧化钾在乙醇溶液中反 应,首次合成出配位聚合物[K(HINR)-(H_2O)]_n,并测定了其晶体结构。该晶体属 单斜晶系, P2_1/c空间群;晶胞参数: a = 0.7888(1)nm, b = 1.38002(2) nm, c = 0.9520(1) nm, β=8.91(1)°;V = 1.0238(2) nm~3; D_c = 1.954 g/cm~3; Z = 4; F(000) = 608; μ(MoKα) = 0.575 mm~(-1)。用DSC,TG-DTG及FT-IR 等分析方法研究了该配位聚合物的热分解机理。在线性升温条件下,该配合物的热 分解包含两个重叠的弱吸热过程和两个强放热分解过程。分解残渣的红外分析表明 ,在271.9 ℃时,分解残渣中有KNCO与羧酸钾,357.1 ℃时,残渣中只有KNC存在 。 相似文献
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Evaluation of chiral oxazolines for the highly enantioselective diethylzinc addition to N-(diphenylphosphinoyl) imines 总被引:2,自引:0,他引:2
Zhang XM Zhang HL Lin WQ Gong LZ Mi AQ Cui X Jiang YZ Yu KB 《The Journal of organic chemistry》2003,68(11):4322-4329
On the basis of the principle that the incorporation of the structurally rigid and conformationally restricted skeleton in beta-amino alcohols is beneficial to the enantioselective diethylzinc addition to imines, a series of chiral oxazolines, which had been designed and conveniently prepared from commercially available (1S,2S)-2-amino-1-phenylpropane-1,3-diol, were applied in the diethylzinc addition to diphenylphosphinoyl imines to give high yields of 68-84% and excellent ee values of 90-95%. The configuration of the product was controlled by the chirality of the carbon bonded to the hydroxyl group in the oxazoline. Oxazolines bearing a para- or meta-substituted phenyl group generally offered higher enantioselectivity than those containing an ortho-substituted phenyl. The X-ray structures of 4f and 4j, in combination with the proposed transition state, preliminarily explained why oxazolines with a para- or meta-substituent on the phenyl group gave higher enantioselectivities than those bearing an ortho-substituent. This successful example using chiral oxazolines to promote the titled reaction implies that a large family of chiral compounds containing an oxazoline ring moiety have the potential to be developed for promoting the highly enantioselective dialkylzinc addition to N-(diphenylphosphinoyl) imines. 相似文献
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The title complex, [CuL][CuCl2(NO3)2] [L=N,N,N′,N′,N″,N″-Hexaisopropyl-2, 2′, 2″-Nitrilotris(2,1-ethoxy)triacetamide], has been synthesized by using an amide-type tripodal ligand with Cu(NO3)2 and then characterized by X-ray single crystal structure analysis. It belongs to monoclinic,space group P21/c with a=1.522 7(2) nm,b=1.277 8(2) nm, c=2.184 5(4) nm, β=93.680(10)°, V=4.241 6(12) nm3, Z=4, Dc=1.401 Mg·m-3, μ=1.189 mm-1, F(000)=1 880, and final R1=0.050 9, wR2=0.125 3. The results show a Cu(Ⅱ) ion was encapsulated by the three chains of the cup-like heptadentate ligand and four-coordinated by the central nitrogen atom and three oxygen atoms from the ligand. CCDC: 648900. 相似文献
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IntroductionMolecularpolymerswithonedimensionalormulti dimensionalstructureassembledthroughhydrogenbondsisanimportantresearchcontentinthesupra molecularchemistryandcrystalengineering .1,2 Withthedevelop mentofnewtypefunctionalmaterialssuchasmolecularmagn… 相似文献
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[Cu(TO)2(H2O)4](PA)2 was prepared by mixing the aqueous solution of 1,2,4-triazol-5-one(TO) and Cu(PA)2. The molecular structure and crystal structure of the title complex was determined by X-ray single crystal diffraction method. The crystal is triclinic, space group with a=0.7321(1)nm,b=0.7474(2)nm,c=1.3649(3)nm;α=88.65(2)°,β=85.63(1)°,γ=63.35(1)°;V=0.6655(2)nm3,Z=1. The Cu2+ coordinated with two TO molecule through its 2-nitrogen atom and four water molecules and showed an octahedral configuration. 相似文献
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