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新法合成手性磷酸锌钠 总被引:1,自引:0,他引:1
对合成手性磷酸锌钠(NaZnPO4·H2O) (CZP)的新方法进行了研究,用Na3PO4·12H2Oand ZnSO4·7H2O作为起始原料,聚乙二醇-400(PEG-400)为表面活性剂,通过一步低热固相反应得到了手性磷酸锌钠。用TG/DTG,XRD, TEM 及 SEM表征了产物。实验结果表明,Na3PO4·12H2O与ZnSO4·7H2O的配比采用不同的p/Zn比(0.9~1.15),在60 ℃下陈化不同的时间(2.0~8.0 h) 所得到的NaZnPO4·H2O,除了结晶度稍为不同之外,晶体的手性结构是一样的。对照实验的结果显示陈化温度及阴离子调控着NaZnPO4·H2O的对映体形态。即,若以ZnSO4·7H2O或Zn(NO3)2·6H2O为锌源,当反应混合物在60 oC陈化时,生成产物的结构是空间群为 P6122 的第一种手性结构,当反应混合物在室温陈化时,生成产物的结构则是空间群为 P6522 的第二种手性结构。 相似文献
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手性Salen配合物水解拆分环氧氯丙烷的动力学 总被引:3,自引:0,他引:3
在立体控制合成有机化合物方面,环氧化合物是一类极有价值的中间体,其中以外消旋混合物形式存在的端基环氧化合物因其价廉易得更是备受关注. 在试图获得高光学纯形式环氧化物的研究中,Jacobsen等[1]对消旋的端基环氧化物的水解动力学拆分(HKR)反应,取得了令人鼓舞的结果,获得了高立体选择性和高产率的手性环氧化物(Y=44%,e.e.>98%)和1,2-二醇化合物(Y=50%,e.e.=98%). 在该项研究中,水是唯一的试剂,手性Salen-CoⅢ显示出良好的催化性能,并得到反应速率与催化剂浓度的平方成正比的反应动力学结果. Jacobsen等[2]又将手性Salen-CoⅢ催化剂固载于聚苯乙烯树脂和硅胶上,用于催化HKR反应,产物的对映选择性又获得进一步提高(Y=41%,e.e.=99%);他们提出了与Salen-CrⅢ配合物催化TMSN3(三甲基叠氮基硅烷)开环环氧化物相似的双金属协同作用机理[3]. 近年来,Salen金属催化的HKR反应广泛地用于高光学纯药物中间体和天然产物的制备. 首先,Jacobsen等[4,5]成功地利用HKR反应高选择性地制备合成出多种β-肾上腺素的关键中间体,并完成了天然产物Muconin的首次全合成. 随后,Gurjar等[6]和Gandour等[7]也通过HKR反应合成了一些在天然产物及药物分子不对称合成中有广泛应用的中间体. 在国内,上海有机化学所的戴立信等[8]利用HKR反应成功地合成了三种β-肾上腺素的构建模块. 吴毓林等[9,10]则通过HKR反应完成了天然番茄枝内酯类化合物4-Deoxyannomontacin的全合成. 所有这些工作,或是重在提高产物的对映体过量及催化剂的活性,或是重在HKR反应在天然产物及药物化学合成中的应用. 由于对外消旋环氧化物的水解拆分反应机理缺乏详细的研究,从而限制了对新型催化剂的开发及对现有催化剂的改进. 本文以各类手性Salen金属配合物为催化剂,通过对水解拆分环氧氯丙烷反应动力学的研究,考察了浓度、温度、催化剂种类对HKR反应的影响,得到一些反应动力学规律;根据动力学实验数据,进一步证实了环氧氯丙烷的水解拆分反应属于双金属催化的过程. 相似文献
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手性和螺旋是生命体系中对生物功能起着重要作用的两大元素。近年来,由于螺旋状配合物特别是手性螺旋配合物被陆续发现在不对称催化、分子识别、手性拆分、非线性光学材料等方面存在较大的应用价值而备受化学家的关注。该文主要针对国内外已报道的手性螺旋配合物的组装方式进行分类总结,概括了手性螺旋配合物的主要构筑途径,包括:氢键作用、配位作用、π-π堆积以及亲银作用。 相似文献
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配位键并非典型价键,所以在模拟金属配合物时若模拟方法和参数选取不当,将会导致不能成键或构型发散。本文将探讨一种能在微机上用分子力学模拟手性金属配合物的新方法,该方法以CsChem3D中MM2为支持力场,通过搭建和优化配合物△,∧[Co(phen)2dppz)]^3+获得其几何构型,并将其构型特征量与文献值或验值进行比较以确定该方法的可靠性。 相似文献
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报道了6种氨基硫脲和D-樟脑磺酸钠与镧系高氯酸盐形成的光学活性配合物,经元素分析确定其组成为C33H51N9O9S6Ln(其中Ln=La,Pr,Nd,Sm,Eu,Gd;Ln:L=1:3),并通过摩尔电导,磁矩,热分析,X射线光电子能谱,红外光谱及紫外-可见光谱等分析测试手段对配合物进行了结构表征和性质研究。配体通过SNO与金属发生配位,Pr^3 和Sm^3 的电子光谱表明存在特征的f-f跃迁,并计算了成键参数(b^1/2),共价键参数(δ)和电子云重排效应参数(β^-),这些数据表明4f轨道在配合物形成过程中存在微弱的参与作用。利用圆二色谱对配合物的光学活性进行了研究。配合物绝对构型为(S)型。金属离子的配位数为9,提出了配合物可能的结合方式,为镧系配合物在生化方面的应用提供了依据。 相似文献
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以5,5'-二硫代双(2-硝基苯甲酸)(H2dna)和1,10-邻菲啰啉(phen)为配体在水热条件下合成了标题配合物,并利用元素分析、傅里叶变换红外光谱、X射线单晶衍射、X射线粉末衍射以及热重分析等技术手段对该配合物进行了结构和性质表征。晶体结构分析表明:配合物为单斜晶系,P2_1/n空间群,a=1.5312(3)nm,b=1.16054(18)nm,c=1.5609(3)nm,β=110.451(2)°,V=2.5990(7)nm~3,Z=4。该配合物为环状双核结构。基于氢键作用邻近的双核分子相连形成一维超分子链。而邻近超分子链又基于S幆O和CH幆π的弱相互作用扩展形成三维超分子网结构。该配合物失水后的产物保持相对稳定,直到245~450℃配体才开始分解,表现出良好的热稳定性。配合物在波长为280 nm的光源激发下,在440 nm有较强的荧光发射峰,且发射峰的形状与H2dna配体相似,但配合物的荧光强度相比H2dna配体有了明显的增强。 相似文献
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选择配体N,N'-双(3-吡啶)丙二酰胺(3-bpma)、1,4-对苯二乙酸(H2pda)和硝酸锌在水热条件下,自组装制备了一个基于双螺旋链的三维超分子锌配合物[Zn(3-bpma)(pda)]n(1),并通过红外光谱、元素分析、热重分析和X射线单晶衍射分析进行了晶体结构表征。 单晶结构分析表明标题锌配合物是正交晶系,Pna21空间群,晶胞参数a=1.62512(11) nm,b=1.15947(8) nm,c=1.19282(8) nm,α=90°,β=90°,γ=90°,V=2.2476(3) nm3,Mr=513.80,Dc=1.518 g/cm3,Z=4,F(000)=1056,R1=0.0381,wR2=0.0669。 金属锌离子被两种桥连配体3-bpma和pda连接形成一种一维双螺旋链状结构,相邻的链间进一步通过氢键作用拓展成为三维超分子网络结构。 标题锌配合物具有强荧光发射特性,而且其对不同的有机溶剂分子和金属离子有显著的荧光传感特性,可以作为检测硝基苯的高灵敏性荧光传感材料。 CCDC:1811967 相似文献
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Ying Ma Yangguang Li Enbo Wang Ying Lu Cao Qin Xinxin Xu 《Journal of Cluster Science》2006,17(2):167-181
Two new materials built from reduced molybdenum (V) phosphates as building blocks and zinc coordination complexes as linkers, (H3O)2[Zn(2,2′-bpy)]4[Zn(H2O)]2[Zn(HPO4)2 (PO4)6(MoO2)12(OH)6] · 6H2O (2,2′-bpy=2,2′-bpyridine) 1 and [Zn(phen)(H2O)2]2[Zn(phen) (H2O)]2[Zn(H2O)]2[Zn(HPO4)4 (PO4)4(MoO2)12 (OH)6] · 7H2O (phen=1,10-phenanthroline) 2, have been synthesized and characterized by elemental analyses, IR, TG, and single crystal X-ray diffraction. Compound 1 is a new 3-D structure which constructed from Zn[P4Mo6]2 dimers bonded together with [Zn(2,2′-bpy)] coordination complexes and [Zn(H2O)] fragments. In compound 2, the Zn[P4Mo6]2 dimeric units are linked by [Zn(phen)(H2O)] coordination complexes and [Zn(H2O)] fragments to form a new 2-D framework. The fluorescent activities of compounds 1 and 2 were reported. The crystal data for the two compounds are the following: 1, triclinic, P−1, a=13.036(3) ?, b=13.765(3) ?, c=14.459(3) ?,
, Z=1; 2, triclinic, P−1, a=12.708(3) ?, b=14.016(3) ?, c=14.646(3) ?,
, Z=1.Dedicated to Professor Michael T. Pope on the occasion of his retirement. 相似文献
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Wenbin Yang Canzhong Lu Chuande Wu Shaofang Lu Dingming Wu Honghui Zhuang 《Journal of Cluster Science》2002,13(1):43-54
Two new members of Mo(V) phosphates were synthesized by hydrothermal methods. (enH2)(enH)[NaMo12O24(OH)6(HPO4)2(H2PO4)6]·(en)4·20H2O(1)(en=H2 NCH2CH2NH2)[HAD-H2]2[HAD-H]2[Zn3Mo12O24(OH)6(PO4)2(HPO4)6]·6H2O (2) (HAD=H2N(CH2)6NH2). Compound 1 crystallized in the space group P2(1)/n, a=15.93120(10) Å, b=15.8946(2) Å, c=17.0665(2) Å, V=4316.02(8), =92.9060(10)°, Z=2. Compound 2 crystallized in the space group P(–1) with a=12.3726(3) Å, b=14.1948(3) Å, c=14.2310(4) Å, =72.7100(10), =65.0230(10), =69.5600(10)°, Z=2089.70(9) Å3, and Z=1. The structure of 1 consists of sandwich-shaped cluster anion [Na{MoV
6O12(OH)3(HPO4)(H2PO4)3}2]3– ({Na(Mo
V
6
)
2
}) held together via intermolecular hydrogen-bonding contacts. For the compound 2, the sandwich-shaped clusters Zn[Mo6O12(OH)3(PO4)(HPO4)3]2 ({Zn(Mo
V
6
)
2} are linked by tetrahedrally-coordinated zinc into layers. Organic cations ([H3N(CH2)6NH3]2+ and [H3N(CH2)6NH2]+) are filled in the spaces between lamellas. The layers are held together by a hydrogen-bonded network, which involves the terminal phosphate P-OH groups, as well as organic cations and several waters of solvation. 相似文献
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A. Dakhlaoui V. Maisonneuve M. Leblanc L. S. Smiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2573-2586
Abstract Chemical preparations, crystal structures, thermal analyses, and IR spectroscopic studies are given for two new hydrogen phosphates templated by 4-amino-2,2,6,6-tetramethylpiperidine: (C9H22N2)2·(H2PO4)·(HPO4)·(F)·H2O (I) and (C9H22N2)·(H2PO4)2(II). The structures are determined by single crystal X-ray diffraction. Both compounds crystallize in the P21/c (N°14) monoclinic space group with the unit cell parameters: a = 14.856 (1) Å, b = 14.092 (2) Å, c = 14.7166 (9) Å, β = 118.434 (7)°, V = 2709.2 (4) Å 3, and Z = 4 for (I) and a = 9.803 (2) Å, c = 0.466 (2) Å, c = 15.640 (8) Å, β = 94.990 (4), V = 1598.68 (7) Å3, and Z = 4 for (II). The structure of I, refined to R = 0.042 and Rw = 0.067 for 6009 reflections (I ≥ 2σ (I)), exhibits infinite inorganic chains ∞((H2PO4)·(HPO4)·(F)·H2O)4? linked together through weak hydrogen bonds to form layers onto which the diprotonated [C9H22N2]2 + amine molecules are anchored. The structure of II, refined to R = 0.060 and Rw = 0.086 for 1435 reflections (I ≥ 2σ (I)), consists of ∞(H2PO4)? (100) layers between which [C9H22N2]2+ cations are inserted. A network of hydrogen bonds connects the different components. IR spectra of I and II show the characteristic bands of amine groups and phosphate anions. 相似文献
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WANG Qing-Wei LI Xiu-Mei SHI Lin-Fang 《结构化学》2008,27(1):11-14
A metal-organic coordination polymer [ZnE.s(phen)(BDC)2(OH)]2 (phen = 1,10- phenanthroline, BDC = benzene-1,4-dicarboxylic acid) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The complex crystallizes in the triclinic system, space group PI with a = 11.199(2), b = 11.593(2), c = 11.865(3)/A, α= 99.330(1), β = 111.506(1), γ = 104.804(1)^o, V= 1328.4(5)A^3, Dc= 1.722 g/cm^3, Z = 1, Mr = 1377.82, F(000) = 692,μ(MoKa) = 2.306 mm^-1, S = 1.093, R= 0.0281 and wR = 0.0756 for 4179 observed reflections (I 〉 2σ(/)). The coordination polyhedron around Zn(II) can be described as a tetrahedron, trigonal bipyramid and octahedron. It is worth noting that the crystal structure of 1 is composed of tetranuclear zinc clusters linked by {ZnO6} units. 相似文献
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A metal-organic coordination polymer [Zn2.5(phen)(BDC)2(OH)]2 (phen = 1,10- phenanthroline, BDC = benzene-1,4-dicarboxylic acid) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The complex crystallizes in the triclinic system, space group P1 with a = 11.199(2), b = 11.593(2), c = 11.865(3) , α = 99.330(1), β = 111.506(1), γ = 104.804(1)°, V = 1328.4(5) 3, Dc = 1.722 g/cm3, Z = 1, Mr = 1377.82, F(000) = 692, μ(MoKα) = 2.306 mm-1, S = 1.093, R = 0.0281 and wR = 0.0756 for 4179 observed reflections (I > 2σ(I)). The coordination polyhedron around Zn(II) can be described as a tetrahedron, trigonal bipyramid and octahedron. It is worth noting that the crystal structure of 1 is composed of tetranuclear zinc clusters linked by {ZnO6} units. 相似文献