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31.
分子组装在材料科学、催化和生物化学中具有潜在的应用前景,所以分子组装引起了化学、固体物理学和生物学等领域科学家们的普遍关注.分子组装常用的方法是使用具有配位能力的金属配合物作为建筑块与过渡金属阳离子反应.  相似文献   
32.
{[Cd(NTO)2(CHZ)]·2H2O}n的合成、分子结构和热分解机理   总被引:4,自引:0,他引:4  
通过3-硝基-1,2,4-三唑-5-酮(NTO)镉与碳酰肼(NH2NHCONHNH2,CHZ)反应制备出了新型配合物{[Cd(NTO)2(CHZ)]·2H2O}n,研究了其分子结构和热分解机理。该配合物的晶体属正交晶系,Pbca空间群,晶体学参数:a=0.8623(1)nm,b=1.8259(4)nm,c=1.9997(3)nm  相似文献   
33.
[Cu(TO)2(H2O)4](PA)2的合成和晶体结构   总被引:4,自引:0,他引:4  
[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   
34.
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   
35.
Taibaihenryiin C 的构型、构象及晶体结构   总被引:1,自引:0,他引:1       下载免费PDF全文
从太白山产的鄂西香茶菜中分离得到新骨架的二萜类化合物TaibaihenryiinC,对其进行X射线衍射晶体结构分析,确定其分子中各取代基的相对构型、环构象及晶体结构.研究表明,C-3位的羟基和C-11位的乙酰氧基以C-20位的甲基为参考均位于β位;分子中的A环为椅式构象,B,C环接近于船式构象,D环接近于信封式构象.特别是在D环中存在较大的扭转角,使D环中有内应力存在,这表明该化合物具有潜在的生理活性.TaibaihenryiinC的晶体结构属正交晶系,P212121空间群,晶胞参数a=0.6162(1)nm,b=1.2730(1)nm,c=2.5193(3)nm,Z=4.在晶体中分子间通过C-3位的-OH氢与C-11位的乙酰氧基上的羰基氧形成分子间氢键,使分子在晶体中沿a轴呈螺旋结构排列.  相似文献   
36.
合成了新型含能配合物[Mn(DAT)6](ClO4)2(DAT=1,5-二氨基四唑), 用X射线单晶衍射法测定了其晶体结构. 该晶体属三方晶系, P3c1空间群, a=b=1.18435(17) nm, c=1.3081(3) nm, α=β=90°, γ=120°, V=1.5891(5) nm3, Z=2. 该配合物分子结构单元中有1个Mn2+离子、6个DAT分子和2个ClO4-离子. 由6个DAT分子中的6个N原子与中心Mn2+离子配位形成六配位、非中心对称的畸变八面体结构. 利用元素分析、差示扫描量热分析(DSC)、热重-微分热重分析(TG-DTG)等方法进行了表征, 研究了其感度性能. 研究结果表明, 该配合物对外界刺激具有很高的响应性和危险性.  相似文献   
37.
[Cd(CHZ)3](ClO4)2的制备和分子结构研究   总被引:10,自引:0,他引:10  
本文报道了高氯酸三碳酰肼合镉(Ⅱ)的制备方法和分子结构。该配合物结构式为[Cd(CHZ)3](ClO4)2。晶体属单斜晶系,P21/n空间群。晶体学参数为:a=1.0281(1) nm, b=0.8617(1) nm, c=2.1360(1) nm,β=100.53°, V=1.8604(3) nm3; Z=4, Dc=2.076 g·cm-3, μ(Mo, Kα)=15.43 cm-1。经全矩最小二乘法对非氢原子坐标和温度因子进行修正。最终偏离因子R=0.0296。在该配合物中,碳酰肼(CHZ)分子作为双齿配体,由羰基氧原子和1位氮原子与Cd配位,形成五员平面螯合环,配合物分子中共有三个这样的螯合环,中心离子为六配位八面体构型;配合物的外界是两个高氯酸根离子,通过库仑力与内界结合在一起。  相似文献   
38.
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   
39.
Treatment of the β-diketiminate-supported ytterbium dichloride LYbCl2(THF)2 1 (L = N,N'-bis(2,6-dimethylphenyl)-2,4-pentanediiminate) with 2 equiv of C5H5Na gave rise to the title complex LYb(C5H5)2 2 (C31H35N2Yb, Mr = 608.65), and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 14.417(2), b = 10.432(2), c = 18.040(4)(A),β= 95.73(2)°, V = 2699.6(9)(A)3, Dc = 1.498 g/cm3, Z = 4,λ(MoKα) = 0.71073(A), μ = 3.485 mm(1, F(000) = 1220, the final R = 0.0304 and wR = 0.0703 for 3962 observed reflections with I > 2σ(I). In the molecular structure of the title complex, the central metal atom Yb is eight-coordinated by two cyclopentadienyl groups and two nitrogen atoms of β- diketiminate group to form a distorted tetrahedral geometry.  相似文献   
40.
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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