首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
Two [MoOCl3(THF)2] molecules are used for detachment of two Cl atoms from [MgCl2(THF)2]. In such reaction a green crystalline salt [Mg(THF)6][MoOCl4THF]2 IV is formed. Compound IV reacts further with 3 equivalents of bis(tetrahydrofuran)magnesium dichloride, yielding a green ionic [Mg2(m?-Cl)3(THF)6][MoOCl4THF] compound V . Compound IV and V vary only in a structure of cation what indicated that the tri-m?-chlorohexakis(tetrahydrofuran)dimagnesium(II) cation in V is really formed in reaction between [Mg(THF)6]2+ cation and [MgCl2(THF)2]. The crystal structure of compounds IV and V has been solved by X-ray diffraction method. The [Mg(THF)6]2+ cation forms the tetragonally distorted octahedron with the magnesium atom in the symmetry centre. In homobimetallic di-octahedral [Mg2(m?-Cl)3(THF)6]+ cation the magnesium atoms are surrounded by three bridging chlorine atoms and three THF molecules. The structures of [MoOCl4THF]? in IV and V are similar. In those anions the molybdenum atom is hexacoordinated with four chlorine atoms in equatorial plane.  相似文献   

3.
Mesityl Oxo Molybdenum and Tungsten Compounds. III. Reactions of WOCl4 with Mesityl Grignard Reagent – X-Ray Crystal Structures of [ClMg(THF)4{OWCl4(THF)}], [Mg(THF)4{OWCl4(THF)}2], and WOMes3(THF)2 The reaction of WOCl4 with MesMgBr (1 : 1) in tetrahydrofuran (THF) proceeds via reduction to tungsten(V), which can be isolated as [MgX(THF)4][WOCl4(THF)] ( 2 ) and by elimination of MgX2 in form of [Mg(THF)4{OWCl4(THF)}2] ( 3 ). The reaction of WOCl4 with MesMgBr in the molar ratio 1 : 4 yields after reduction [WOMes3(THF)] · THF ( 4 ). All complexes are characterized by X-ray structure analyses. In 2 and 3 [WOCl4(THF)] anions are linked via their oxo ligands to the magnesium ions. 4 has a distorted trigonal bipyramidal coordination sphere.  相似文献   

4.
Syntheses and Crystal Structure Analyses of [SbI3(SbMe3)(THF)]2 and [Li(THF)4]2[Bi2Cl8(THF)2] The reaction of Me3Sb with SbI3 in tetrahydrofuran (THF) gives [SbI3(SbMe3)(THF)]2 ( 1 ). [Li(THF)4]2[Bi2Cl8(THF)2] ( 2 ) is formed by reaction of LiCl and BiCl3 in tetrahydrofuran. The structures of ( 1 ) and ( 2 ) have been determined by X-ray diffractometry. Both structures contain centrosymmetric dimers with the geometry of edge sharing octahedra.  相似文献   

5.
林观阳  卫革成 《结构化学》1992,11(3):200-203
标题化合物SmCl_3(THF)_4(M_r=545.2)晶体属正交晶系,空间群为Pdd 2。晶胞参数为a=9.211(4),6=16.436(6),c=29.666(12);V=4491(3) ~3;Z=8,D_c=1.61g.cm~(-3),F(000)=2184,μ_c=30.3cm~(-1)。最终的偏因子R=0.063,R_(to)=0.062。Sm~(3+)与三个Cl~-及四个四氢呋喃分子中氧原子配位,形成一个五角双锥的空间结构,其中二个氯原子分别位于二个顶点位置。分子中有一个通过Sm~(3+)及Cl~-的C_2轴。Sm-Cl及Sm-0的平均键长分别为2.683(5)及2.469(11)。  相似文献   

6.
Crystal Structures of the Triarylzincates [Mg2Br3(THF)6][ZnPh3] and [MgBr(THF)5][ZnMes3] The title compounds were obtained from reactions of the phosphoraneiminato complex [ZnBr(NPMe3)]4 with excess Grignard reagents RMgBr (R = C6H5, 2,4,6-(CH3)3–C6H2) in THF solution. According to X-ray structure determinations the [ZnR3] ions contain zinc atoms which are coordinated in a planar fashion with Zn–C distances of 200.7 pm (R = Ph) and 203.4 pm (R = Mes) in average.  相似文献   

7.
<正> The bonding of complexes [EuCl3(THF)4] , [NdCl3(THF)4] and [UI3 (THF)4] has been studied by using SCC-DV-Xa method. It was found that THF helps to construct a polyhedral molecule and therefore considerably shortens M-X distances. The behaviour of f-orbitals in bonding was studied and discussed herein.  相似文献   

8.
Syntheses and Crystal Structures of the Rare-Earth Complexes [LaI2(THF)5]+I3?, [SmCl3(THF)4], [ErCl2(THF)5]+ [ErCl4(THF)2]?, [ErCl3(DME)2], and [Na(18-Crown-6)(THF)2]+[YbBr4(THF)2]? [LaI2(THF)5]+I3? ( 1 ) is obtained as red crystals from lanthanum powder and 1,2-diiodoethane in THF on exposure to light. Space group Pbcn, Z = 4, lattice dimensions at ?83°C: a = 1264.9, b = 2218.9, c = 1199.1 pm, R = 0.031. The lanthanum atom of the cation of 1 is coordinated with iodine atoms in the axial positions in a pentagonal-bipyramidal way. [SmCl3(THF)4] ( 2 ) originates as colourless crystals on heating SmCl3 with excess THF in the presence of Me3SiNPEt3. Space group P21/c, Z = 8, lattice dimensions at ?50°C: a = 3092.7, b = 826.2, c = 1758.3 pm, β = 93.85°, R = 0.054. Just like the known sample that crystallizes within the space group F2dd, 2 forms monomeric molecules in which the samarium atom is coordinated with two chlorine atoms in the axial positions in a distorted pentagonal-bipyramidal way. [ErCl2(THF)5]+[ErCl4(THF)2]? ( 3 ). Pale pink single crystals of 3 were prepared according to the described method by reaction of erbium powder with trimethylchlorosilane and methanol in THF. Space group C2/c, Z = 4, lattice dimensions at ?50°C: a = 1246.3, b = 1145.7, c = 2726.0 pm, β = 91.293°, R = 0.036. The erbium atom of the cation of 3 has a pentagonal-bipyramidal coordination with the chlorine atoms in the axial positions. Within the anion the THF molecules are in trans-arrangement of the octahedrally coordinated erbium atom. [ErC13(DME)2] ( 4 ) originates as pink single crystals from 3 with excess boiling 1,2-dimethoxyethane. Space group P21/c, Z = 4, lattice dimensions at ?50°C: a = 1137.2, b = 886.5, c = 1561.1 pm, β = 104.746°, R = 0.032. 4 forms monomeric molecules in which the erbium atom has a pentagonal-bipyramidal surrounding with two chlorine atoms in the axial positions. [Na(18-Krone-6)(THF)2]+ [YbBr4(THF)2]? ( 5 ) is formed as by-product by the reaction of YbBr3 with NaN(SiMe3)2 in THF in the presence-of 18-crown-6 forming colourless crystals. Space group P1 , Z = 1, lattice dimensions at ?70°C: a = 934.6, b = 988.9, c = 1208.0 pm, α = 73.82°, β = 72.98°, γ = 76.89°, R = 0.029. 5 contains isolated [YbBr4(THF)2]?ions, in which the THF molecules are arranged in trans-position.  相似文献   

9.
Convenient methods to prepare solvated rhenium oxochlorides are described; these compounds should serve as useful starting materials for rhenium chemistry. Treatment of perrhenic acid, HReO(4), with chlorotrimethylsilane or with thionyl chloride, followed by addition of tetrahydrofuran, forms the new oxochloride complexes ReO(3)Cl(THF)(2) and ReOCl(4)(THF), respectively. Small amounts of two dinuclear oxochlorides, which evidently resulted from adventitious hydrolysis, were also isolated: Re(2)O(3)Cl(6)L(2), where L = THF or H(2)O. All four compounds were characterized by X-ray crystallography. The rhenium(vii) complex ReO(3)Cl(THF)(2) adopts a distorted octahedral geometry in which the three oxo ligands are in a facial arrangement; the rhenium(vi) complex ReOCl(4)(THF) adopts a trans octahedral structure. The two dinuclear rhenium(vi) compounds both have a single, nearly linear, bridging oxo group; on each Re center, the three terminal chlorides adopt a mer arrangement, and the terminal oxo and the coordinated Lewis base are mutually trans. The water ligand in the aqua complex is hydrogen bonded to nearby THF molecules. IR data are given.  相似文献   

10.
11.
12.
13.
Conclusions By reacting MnCl2 and NaBH4 in THF, the complex MnOBH4)2 (THF)3 was obtained and characterized by chemical analysis and physicochemical methods.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1712–1716, August, 1987.  相似文献   

14.
我们曾测定NdCl_3·4THF的晶体结构,并研究了它对双烯烃聚合的活化作用.本文报导含二甲氧基乙烷(Dimethoxyethane,简称DME)的SmCl_3(DME)·2THF的制备及其单晶结构,以利于对稀土催化双烯烃聚合反应机理作出更好的解释.  相似文献   

15.
Influence of 3A molecular sieve on tetrahydrofuran (THF) hydrate formation   总被引:1,自引:0,他引:1  
Visual observation of the THF hydrate formation process in the presence of a 3A molecular sieve has been made at normal atmosphere and below a temperature of zero by microscopy. The results indicate that a 3A molecular sieve can induce the nucleation of the THF hydrate and promote the THF hydrate growth. With the existence of a 3A molecular sieve, the growth rate of THF hydrate is between 0.01 and 0.05 μm/s. In comparison with the system without any 3A molecular sieve, the growth rate increases about 4 nm/s. After the THF hydrate grows into megacryst, the crystals will recombine and partially change under the same condition.  相似文献   

16.
The thermal behavior of kaolinite–urea intercalation complex was investigated by thermogravimetry–differential scanning calorimetry (TG–DSC), X-ray diffraction (XRD), and fourier transform infrared spectroscopy (FTIR). In addition, the interaction mode of urea molecules intercalated into the kaolinite gallery was studied by means of molecular dynamics simulation. Three main mass losses were observed at 136 °C, in the range of 210–270 °C, and at 500 °C in the TG–DSC curves, which were, respectively, attributed to (1) melting of the surface-adsorbed urea, (2) removal of the intercalated urea, and (3) dehydroxylation of the deintercalated kaolinite. The three DSC endothermic peaks at 218, 250, and 261 °C were related to the successive removals of intercalated urea with three different distribution structures. Based on the angle between the dipole moment vector of urea and the basal surface of kaolinite, the three urea models could be described as follows: (1) Type A, the dipole moment vector is nearly parallel to the basal surface of kaolinite; (2) Type B, the dipole moment vector points to the silica tetrahedron with the angle between it and the basal surface of kaolinite ranging from 20°to 40°; and (3) Type C, the dipole moment vector is nearly perpendicular to the basal surface of kaolinite. The three distribution structures of urea molecules were validated by the results of the molecular dynamics simulation. Furthermore, the thermal behavior of the kaolinite–urea intercalation complex investigated by TG–DSC was also supported by FTIR and XRD analyses.  相似文献   

17.
Organometallic Compounds of the Lanthanides. 88. Monomeric Lanthanide(III) Amides: Synthesis and X-Ray Crystal Structure of [Nd{N(C6H5)(SiMe3)}3(THF)], [Li(THF)2(μ-Cl)2Nd{N(C6H3Me2-2,6)(SiMe3)}2(THF)], and [ClNd{N(C6H3-iso-Pr2-2,6)(SiMe3)} 2(THF)] A series of lanthanide(III) amides [Ln{N(C6H5) · (SiMe3)}3(THF)x] [Ln = Y ( 1 ), La ( 2 ), Nd ( 3 ), Sm ( 4 ), Eu ( 5 ), Tb ( 6 ), Er ( 8 ), Yb ( 9 ), Lu ( 10 )] could be prepared by the reaction of lanthanide trichlorides, LnCl3, with LiN(C6H5)(SiMe3). Treatment of NdCl3(THF)2 and LuCl3(THF)3 with the lithium salts of the bulky amides [N(C6H3R2-2,6)(SiMe3)]? (R = Me, iso-Pr) results in the formation of the lanthanide diamides [Li(THF)2(μ-Cl)2Nd{N(C6H3Me2-2, 6)(SiMe3)}2(THF)] ( 11 ) and [ClLn{N(C6H3-iso-Pr2-2,6)(SiMe3)} 2(THF)] [Ln = Nd ( 12 ), Lu ( 13 )], respectively. The 1H- and 13C-NMR and mass spectra of the new compounds as well as the X-ray crystal structures of the neodymium derivatives 3 , 11 and 12 are discussed.  相似文献   

18.
The reaction between 1.5 equiv of elemental iodine and rare earth metals in powder form in THF at room temperature gives the rare earth triiodides LnI(3)(THF)(n)() in good yields. Purification by Soxhlet extraction of the crude solids with THF reliably gives the THF adducts LnI(3)(THF)(4) [Ln = La, Pr] and LnI(3)(THF)(3.5) [Ln = Nd, Sm, Gd, Dy, Er, Tm, Y] as microcrystalline solids. X-ray crystallography reveals that the early, larger lanthanide iodide PrI(3)(THF)(4) crystallizes as discrete molecules having a pentagonal bipyramidal structure, whereas the later, smaller lanthanide iodides LnI(3)(THF)(3.5) [Ln = Nd, Gd, Y] crystallize as solvent-separated ion pairs [LnI(2)(THF)(5)][LnI(4)(THF)(2)] in which the cations adopt a pentagonal bipyramidal geometry and the anions adopt an octahedral geometry in the solid state.  相似文献   

19.
The reactions of zinc alkyls with tert-butylphosphonic acid in 2 : 1 and 1 : 1 molar ratios afforded [[(ZnMe)(4-)(THF)2][tBuPO3]2] (2) and [[(ZnEt)3(Zn(THF))3][tBuPO3]4[mu3-OEt]] (3), respectively. Compounds 2 and 3 have been fully characterised by means of spectroscopic and analytical methods. Single-crystal X-ray diffraction studies revealed that zinc phosphonates 2 and 3 are tetra- and hexa-nuclear, respectively. This is in contrast to the dodecanuclear zinc phosphonate [[Zn2(THF)2(ZnEt)6Zn4(mu4-O)][(tBuPO3)8]] (1) obtained in a 1.5 : 1 reaction between zinc alkyls and tBuP(O)(OH)2.  相似文献   

20.
Triphenyl[tris(tetrahydrofuran)]ytterbium, Ph3Yb(THF)3 (1), was synthesized in high yields by the reaction of Yb with an excess of Ph2Hg or Ph3Bi in the presence of catalytic amounts of YbI2(THF)4 as well as by the reaction of Ph2Yb(THF)2 (2) with Ph2Hg or Ph3Bi. The crystal structure of complex1 was studied by X-ray structural analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 163–166, January, 1998.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号