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1.
张建平  杨春  周家宏 《化学学报》2012,(14):1555-1560
以CoIIIW11和有机硅烷为原料,在pH=1,乙醇-水(体积比=2∶1)的混合溶剂中,首次合成了Keggin型有机硅取代的钨钴酸盐[CoIIIW11O40(SiR)2]5-(CoIIIW11(SiR)2,R=CH=CH2,OH).这里,乙醇作为共溶剂增加硅烷在溶液中的溶解度,使CoIIIW11在转化为饱和结构之前能够快速与硅烷相遇并反应.产物的组成和结构用IR,UV-Vis,NMR,TG-DTA,元素分析等技术进行了全面表征.结果显示,两个SiR基团进入了CoIIIW11的空位,并形成Si—O—Si桥,得到与先前报道的硅取代钨硅酸盐和钨磷酸盐相似的结构.还运用此条件成功合成了以往需要在固-液相转移条件下合成的[PW11O40(SiR)2]3-[PW11(SiR)2,R=CH=CH2,OH],进一步证明了此方法在合成有机硅取代的多金属氧酸盐方面的可行性和通用性.  相似文献   

2.
通过NiCl2.6H2O与双齿配体2-(二苯基膦)乙醇(Ph2PCH2CH2OH)或其氧化物2-(二苯基氧膦)乙醇[Ph2P(O)CH2CH2OH]的反应,制得两种结构新颖的阳离子型镍配合物[NiCl(Ph2PCH2CH2OH)2(H2O)]^+Cl^-(1)和[Ni(Ph2P(O)CH2CH2OH)4]^2+[NiCl4]^2-(2).通过元素分析、31P核磁共振及X射线单晶衍射对配合物1和2的结构进行了表征.配合物1的晶体属单斜晶系,C2/c空间群,中心金属Ni具有六配位八面体几何构型.配合物2属四方晶系,I4(1)/a空间群,中心原子Ni与P==O基团中的O配位形成平面四边形构型.  相似文献   

3.
利用水热合成法制备了基于Keggin结构阴离子的1D链状化合物[Cu(en)2]2[Cu(en)2(H2O)][PW11.5Cu0.5O40].OH.3H2O,并经红外、紫外和X射线单晶衍射等手段进行了表征.标题化合物属于单斜晶系,P21/c空间群,晶胞参数:a=1.266 25(10),b=2.145 45(19),c=2.455 95(18)nm,β=114.919(3),V=6.050 9(8)nm3,Z=4,R1=0.068 1,wR2=0.146 8.  相似文献   

4.
杂多化合物SiW11O398-的有机硅衍生物早在1978年就由Knoth报道[1],后来又有人报道了α-PW11O397-和α-PW9MO2O397-的有机硅衍生物[2,3].该类衍生物在抗HIV-1方面有重要的用途[4,5],因而,近年来引起了人们极大的重视.1996年Thouvenot及其合作者研究了三缺位杂多阴离子与有机硅的反应,并在相转移条件下合成了一些杂多阴离子的有机硅衍生物[6~9],但到目前为止,有关杂多化合物的有机硅衍生物报道还很少,该类化合物的晶体结构报道更少.本文报道了化合物(TBA)3[α-A-PW9O34(CH3SiO)3(CH3Si)](1)(TBA为四丁基铵盐的缩写)的合成和晶体结构.  相似文献   

5.
我们曾用EXAFS和X射线单晶衍射研究了M_3W_2Cl_9类双钨簇合物的结构,发现簇胳[W_2Cl_9]~(3-)的结构很牢固,改变阳离子M~+的性质和大小,都不会改变其结构。W_2Cl_9(RO)_4(R′OH)_2类簇合物与M_3W_2Cl_9类似,具有一个双钨簇胳。Anderson等曾研究R为甲基或乙基的两个簇合物的单晶结构,正四价的两个钨原子间用双键及两个氧桥键相联接。与M_3W_2Cl_9另一不同处是取代基RO及R′OH与钨原子直接相联,其间还形成氢键,故RO或R′OH对簇胳的影响要大于M_3W_2Cl_9中阳离子M~+。本文合成6种具有不同取代基的W_2Cl_4·(RO)_4(ROH)_2化合物,用EXAFS研究其结构,以期了解不同取代基对簇胳结构的影响。  相似文献   

6.
合成了二维层状单缺位Keggin结构阴离子稀土衍生物Na3H8[La(PW11O39)2].19H2O,并用IR和X射线单晶衍射等手段对其进行了表征.该晶体属于单斜晶系,P2/n空间群,a=1.343 43(8)nm,b=1.259 35(7)nm,c=3.541 8(2)nm,β=99.151 0(10)°,V=5.915 9(6)nm3,Z=2,R1=0.042 9,wR2=0.119 4.化合物阴离子[La(PWO)]11-通过NaO桥联形成一维链,再通过NaO桥联形成二维层状结构.  相似文献   

7.
铁取代钨硅酸盐位置异构体的合成、表征及电化学性质   总被引:5,自引:0,他引:5  
取代型杂多酸盐( HPC)具有金属卟啉的类似结构 ,它可以代替金属卟啉在很多反应中作催化剂 [1],被称为无机金属卟啉。 Hill[2],Neumann[3]分别报道了过渡元素单取代的杂多阴离子 [PW11M(H2O)O39]n-, [SiW11Ru(H2O)O39]n-对烯烃环氧化反应具有催化活性。目前,在单取代的杂多配合物中,β异构体的报道很少,我们发现,某些单取代金属衍生物中,β异构体具有良好的催化活性,具有明显的应用前景。继过去的工作 [4],我们又研究了过渡元素取代的 11-系列杂多阴离子的某些性质。有关α-XW11Fe(H2O)O39n-( X=Si, P, Ge, As…  相似文献   

8.
A POMs-based 3D zeolike ionic crystal 1, {[Co(dpdo)2(CH3CN)(H2O)2]2(SiMo12O40)- (HEO)2}n (dpdo = 4,4'-bipyridine-N,N'-dioxide), was constructed via self-assembly by embedding Keggintype [SiMo12O40]^4- polyanions within the intercrystalline voids as pillars and structurally characterized. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a = 11.430(3), b = 12.242(3), c = 14.279(3)A, α = 106.196(4),β = 94.316(4), γ = 98.294(3)°, V = 1884.5(7)A^3 Z = 1, C44H50N10O54CoEMo12Si, Mr = 2880.17, Dc = 2.538 g/cm^3, p = 2.484 mm^-1,F(000) = 1388, the final R = 0.0383 and wR = 0.1096 for 7753 observed reflections with I 〉 2σ(I). Flack factor is 0.22(3). Compound 1 is a pillar-layered framework with the [SiMo12O40]^4- anions linearly located on the square voids between the 2D bilayers which are formed by the dpdo ligands and cobalt(II) ions.  相似文献   

9.
钨磷酸;二甲胺;Dawson结构多金属氧酸电荷转移化合物[CH3NH2CH3]2[CH3NHCH3]4H4[P2W18O62]·H2O的合成、表征及晶体结构  相似文献   

10.
合成了二维层状单缺位Keggin结构阴离子稀土衍生物Na3H8[La(PW11O39)2].19H2O,并用IR和X射线单晶衍射等手段对其进行了表征.该晶体属于单斜晶系,P2/n空间群,a=1.343 43(8)nm,b=1.259 35(7)nm,c=3.541 8(2)nm,β=99.151 0(10)°,V=5.915 9(6)nm3,Z=2,R1=0.042 9,wR2=0.119 4.化合物阴离子[La(PWO)]11-通过NaO桥联形成一维链,再通过NaO桥联形成二维层状结构.  相似文献   

11.
The isomerization of CH3S(OH)CH2 to CH3S(O)CH3 in the absence and presence of water has been investigated at the G3XMP2//B3LYP/6-311 + G(2df, p) level. The naked isomerization, the reaction without water, gives the high barrier height (21.56 kcal.mol^-1). Three models are constructed to describe the water influence on the isomerization, that is, water molecules are the catalyst and the microsolvation, and water molecules act as the catalyst and microsolvation simultaneously. Our results show that the isomerization barrier heights of CH3S(OH)CH2 to CH3S(O)CH3 are reduced by 12.32, 11.04, and 7.80 kcal.mol^-1, respectively, when one, two, and three water molecules are performed as catalyst, in contrast to the naked isomerization. Moreover, the rate constants of the isomerization are calculated using the transition state theory with the Wigner tunneling correction over the temperature range of 240-425 K. We find that the rate constant of a single water molecule as the catalyst is 1.58 times larger than the naked isomerization at 325 K, whereas it is slower by 6 orders of magnitude when water molecule serves as the microsolvation at 325 K, compared to naked reaction. So the water-catalyzed isomerization of CH3S(OH)CH2 to CH3S(O)CH3 is predicted to be the key role in lowering the activation energy. The isomerization involving water molecules acting as mierosolvation is unfavorable under atmospheric conditions.  相似文献   

12.
采用密度泛函理论方法对3,4-二-O-乙酰基-L-阿拉伯烯糖与HR—CH2—CH=CH2(R=O,CH2,NH,S)反应的Ferrier重排反应机理进行了研究,并通过自洽场极化连续模型(PCM)模拟了苯和二氯化碳溶剂对反应历程的影响,计算了相应结构的单点能,考虑了2条可能的反应途径,获得了较优反应途径和反应速率控制步骤.研究表明:苯和二氯化碳溶剂的溶剂效应未对反应历程产生明显影响.R基电负性越大、体积越大以及H+的存在,均有利于该重排反应进行.  相似文献   

13.
合成了4种主族元素取代的钨砷杂多配合物,通过ICP和TG曲线确定其通式为:K11,12〔M(AsW11O39)2〕.xH2O和K3,4[AsZ(OH2)W11O39].xH2O(M=Pb2 ,Bi3 ;Z=Sn4 ,Sb3 ).采用IR,UV,XRD,XPS,183W NMR等方法证明其结构为β2-Keg-gin结构,用极谱和循环伏安法研究了配合物的氧化还原性和热稳定性,结果表明:所合成的配合物只有一步双电子还原过程,电位较高,表现出强氧化性;配合物将在550℃~600℃范围内分解.  相似文献   

14.
[ZnN(CH2CH2NH2)2(CH2CH2N=CHC6H4O)]·Pic的合成与晶体结构   总被引:1,自引:0,他引:1  
在不加任何碱的条件下,三[2-(亚水杨基胺)乙基]胺与苦味酸锌[Zn(Pic)26H2O]在乙醇中反应,得到了较为少见的多胺单缩合西夫碱配体的配合物[ZnN(CH2CH2NH2)2(CH2CH2N=CH-C6H4O)]Pic。化学式为C19H23N7O8Zn,Mr=542.81,晶体属三斜晶系,空间群为P,晶胞参数为a=0.7494(3),b=1.1917(5),c=1.3142(6)nm,a=78.111(7),b=79.093(7),g=78.577(7),V=1.1121(8)nm3,Dc=1.621g/cm3,m(MoKa)=1.167mm-1,Z=2,F(000)=560,在1.602s(I)的可观测点为2433个,最终偏离因子R=0.0555,wR=0.1139。配合物中Zn(II)与配体的4个N原子和1个O原子配位形成变形的三角双锥结构,桥头N和O为锥顶,4个配位N中桥头N与金属离子的配位作用最弱。晶体通过p-p堆积和分子内、分子间的氢键作用形成二维层状超分子结构。  相似文献   

15.
研究了一种可循环并且环境友好的催化体系:[π-C5H5N(CH2)15CH3]3[PMoW3O24]/过氧化氢/乙酸乙酯/烯烃.此体系不仅可以催化烯烃的环氧化反应,而且避免了对含氯溶剂的使用.反应在过氧化氢/乙酸乙酯的两相体系中进行,可以将多种烯烃转化为相应的环氧化物,且产率较高.此催化剂具有反应控制相转移的特征,反应结束后可以回收再利用.采用Raman,IR,^31P MAS NMR和^31P NMR等手段对新鲜及重复使用过的催化剂进行表征.结果表明:新鲜催化剂[π-C5H5N(CH2)15CH3]3[PMoW3O24]是一种混合物,含有多种过氧磷钼钨酸盐,如{PO4[MoO(O2)2]4}^3-,[(PO4){Mo3WO20}]^3-,[(PO4){Mo2W2O20}]^3-,[(PO4){MoW3O20}]^3-和{PO4[WO(O2)2]4}^3-.当过氧化氢被完全消耗后,这些小的活性物种就会聚合成具有混合多原子的Keggin型杂多阴离子,形成M-Ob—M(M=W或Mo)和M-Oc-M键.  相似文献   

16.
段文胜  刘斌  孙占国  杨斌盛 《化学学报》2011,69(15):1789-1794
合成了一种新型的4-甲基-水杨酸铬(Ⅲ)配合物[Cr(Ⅲ)(4-Me-SA)(en)2]Cl·0.5CH3OH(4-Me-SA=4-甲基-水杨酸,en=乙二胺),利用X射线晶体衍射和元素分析对其进行了结构表征.通过紫外-可见吸收光谱、荧光光谱、电导率等方法,研究了β-环糊精对两种铬配合物[Cr(Ⅲ)(4-Me-SA)(...  相似文献   

17.
Three new inorganic-organic composite polyoxotungstates [Cu(2,2'-bpy)2]5[α-PW11.5Cu0.5O40]·2H2O 1, [Co(2,2'-bpy)2(N3)2]4H3[α-PW12O40]·3H2O 2 and [Cu(2,2'-bpy)2(4,4'-bpy)]2[α-GeW12O40]-4H2O 3 (2,2'-bpy = 2,2'-bipyridine, 4,4'-bpy = 4,4'-bipyridine) have been hydrothermally synthesized and structurally characterized. 1 crystallizes in the orthorhombic space group Pna21 with a = 27.847(3), b = 21.597(2), c = 20.1179(19)A, V= 12099(2)A^3, Z= 4, GOF= 1.038, R = 0.0427 and wR = 0.1035; 2 belongs to the triclinic space group P1^- with a = 12.31150(10), b = 16.1954(4), c = 19.36290(10)A, α = 99.366(11), β =105.168(8), γ = 111.836(8)°, V = 3309.98(9)A3, Z = l, GOF = 1.024, R = 0.0739 and wR = 0.2216; and 3 crystallizes in the monoclinic space group P21/n with a = 12.858(4), b = 20.943(6), c = 15.598(5)A, β = 102.338(5)°, V= 4103(2)A3, Z = 2, GOF = 1.026, R = 0.0557 and wR = 0.1316. The common structural features of 1-3 are that their molecular structures all consist of a saturated a-Keggin polyoxoanion and several discrete metal-organic moieties. Intriguingly, 2 and 3 are composed of metal-organic coordination moieties with two mixed ligands.  相似文献   

18.
以2-氨基乙醇(EA)和邻菲咯啉(PHEN)为配体合成了新配合物[Co(PHEN)2(EA)](ClO4)2.H2O.CH3OH,其结构经IR,元素分析和X-射线单晶衍射法表征。1属单斜晶系,空间群为P2(1)/n,晶胞参数a=0.863 0(7)nm,b=1.348 8(11)nm,c=2.520 6(20)nm,β=91.503(12)°,V=2.933(4)nm3,Z=4,R=0.074 4,wR=0.170 3。衍射数据[I>2σ(I)]为2 602。在1中,Co(Ⅱ)原子与五个氮原子和一个氧原子配位,处于畸变的八面体配位环境。  相似文献   

19.
The polyoxoanion incorporated {Mn(CO)3^+} complex, (n-Bu4N)2[Mo6O16(OCH3)2{HOCH2C(CH2O)3}2·{Mn(CO)3}2](1), has been synthesized by the reaction of (n-Bu4N)4[Mo8O26] with Mn(CO)5Br in methanol, in the presence of C(CH2OH)4. The complex 1 has been characterized by IR, UV-Vis, X-ray single crystal diffraction, and TG. Crystal data for the complex 1:C25H48MnMo3NO16 (1), Triclinic Pi, a=0.9405(3) nm, b=1.3351(4) nm, c=1.5455(4) nm, α=103.206(5)°, β=102.165(5)°, γ=100.784(5)°, V=1.7896(9) nm^3, Z=2, R1=0.0703, wR2= 0.1495. The structure analysis of complex 1 shows that the complex consists of two tetrabutylammonium cations and a polyoxomolybdate anion that incorporates two fac-Mn(CO)3^+ units. The anion of complex 1 can be considered as the dimer of two rhomb-like anions by sharing of two comers.  相似文献   

20.
The title compounds have been respectively synthesized by solution process and solvothermal reaction, and their crystal structures were determined by X-ray diffraction method. For (CH3CH2CH2CH2NH3)6(BiI6)(I)2I3 1, it crystallizes in tficlinic, space group P1^- with Mr = 2049.76, a = 8.5719(1), b = 11.7461(3), c = 15.700(1)A, V = 1451.4(1)A^3, Z = 1, Dc = 2.345 g/cm^3, F(000) = 924, μ(MoKα) = 8.907 mm^-1, T = 293(2) K, the final R = 0.0655 and wR = 0.0804 for 2399 observed reflections with I 〉 2σ(I). For (NH3CH2CH2NH3)2Bi2I10 2, it crystallizes in monoclinic, space group P21/n with Mr= 1811.20, a = 8.434(4), b = 13.862(6), c = 13.362(6)A, V = 1499.9(12)A^3, Z = 2, Dc = 4.010 g/cm^3, F(000) = 1536,μ(MoKα) = 22.007 mm^-1, T = 293(2) K, the final R = 0.0584 and wR = 0.1451 for 1798 observed reflections with I 〉 2σ(I). The structures of 1 and 2 contain halobismuthate monomer and dimers, respectively. It is noteworthy that the dimers and their organic counters in 2 connect each other by N…I hydrogen bonds to form a layered structure, and the electrostatic interactions and crystal packing forces between layers give rise to the packing of the crystal. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.13 and 2.01 eV, respectively.  相似文献   

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