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1.
The neodymium borohydride [Li(thf)4]2[Nd2(μ‐Cl)2(BH4)6(thf)2] was synthesized from neodymium chloride and lithium borohydride. The compound crystallized in the triclinic crystal system, space group (No. 2) with the cell constants a = 14.8613(11), b = 17.8715(13), c = 23.5846(18) Å, α = 100.760(6), β = 90.648(6) and γ = 103.294(6)°. Each neodymium atom is coordinated by three borohydride anions and a THF molecule whereas two neodymium cations are bridged through two chloro ligands. The charge of the [Nd2(μ‐Cl)2(BH4)6(thf)2]2− anion, which represents the first structurally characterized binuclear mixed borohydride chlorido complex, is compensated by two [Li(thf)4]+ cations.  相似文献   

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.
Syntheses and Structures of the Polymeric Silver Complexes [Ag2Cl2(dppbp)3], [Ag2(SPh)2(dppe)3] and [Ag2(SPh)2(triphos)] as well as the Silver Chalcogenido Clusters [Ag7(SPh)7(dppm)3], {[Ag7(TePh)7(dppp)3]2(dppp)}, and [Ag22Cl(SPh)10(PhCOO)11(dmf)3] The reaction of silver carboxylate with silylated chalcogen compounds have been found to have a possibility for the synthesis of metal‐chalcogenide‐custers. Especially phosphine ligands have been found to be useful in stabilising the cluster cores. Some of the silver carboxylate phosphine complexes, which are formed in‐situ, ([Ag2Cl2(dppbp)3] ( 1 )) and some silver chalcogen complexes ([Ag2(SPh)2(dppe)3] ( 2 ) und [Ag2(SPh)2(triphos)] ( 3 )), could be isolated and characterised by X‐ray diffraction. Using special reaction conditions, it is possible to isolate cluster species like [Ag7(SPh)7(dppm)3] ( 4 ), {[Ag7(TePh)7(dppp)3]2(dppp)} ( 5 ) and [Ag22Cl(SPh)10(PhCOO)11(dmf)3] ( 6 ) beside the complex compounds. 1: Space group P21/n (No. 14), Z = 2, a = 1336, 1(2), b = 2081, 2(5), c = 2015, 4(4) pm, β = 99, 87(2)°; 2: Space group P21/n (No. 14), Z = 2, a = 1416, 1(3), b = 1874, 7(4), c = 1444, 8(3) pm, β = 93, 26(3)°; 3: Space group P21/n (No. 14), Z = 4, a = 1456, 8(3, b = 1890, 2(4), c = 1916, 1(4) pm, β = 99, 11(3)°; 4: Space group P21/n (No. 14), Z = 4, a = 1570, 2(3), b = 2798, 5(6), c = 2752, 7(6) pm, β = 98, 02(3)°; 5: Space group P1 (No. 2), Z = 2, a = 2115, 5(4), b = 2553, 3(5), c = 3188, 7(6) pm, α = 68, 87(3)°, β = 74, 05(3)°, γ = 69, 70(3)°; 6: Space group P1 (No. 2), Z = 2, a = 1583, 0(3), b = 1709, 6(3), c = 2990, 0(6) pm, α = 80, 41(3)°, β = 88, 86(3)°, γ = 71, 10(3)°).  相似文献   

4.
The compounds [Hg2(μ—SePh)2(SePh)2(PPh3)2] ( I ) and [Hg3Br3(μ—SePh)3] · 2 DMSO ( II ) are formed by reactions of [Hg(SePh)2] with PPh3 in THF( I ) or with HgBr2 in DMSO ( II ) at room temperature. X—ray crystallography reveals that the cluster I consists of a distorted square built by each two Hg and Se atoms. The Hg atoms have almost tetrahedral co‐ordination environments formed by selenium atoms of two (μ‐SePh) ligands and Se and P atoms of terminal SePh and PPh3 ligands. The compound II is a six‐membered ring with alternating Hg and Se atoms in the chair conformation. Two DMSO molecules occupy positions below and above the [Hg3Se3] ring with the oxygen atoms directed to the centre of the ring.  相似文献   

5.
[Hg(sulfamethoxazolato)2]·2DMSO ( 1 ) and [Cu2(CH3COO)4(sulfa‐methoxazole)2] ( 2 ) can be obtained by the reaction of sulfamethoxazole with mercury acetate or copper acetate in methanol. The structures of the two complexes were characterized by single crystal X—ray diffractometry. Compound 1 consists of sulfamethoxazolato ligands bridging the metal ions building an unidimensional chain. Two solvent dimethylsulfoxide molecules are involved via N‐H···O hydrogen bridges. The mercury atom shows a linear primary coordination arrangement formed by two trans deprotonated sulfonamidic nitrogen atoms. The overall coordination around the metal atom may be regarded as a strongly distorted octahedron when the interactions of mercury with four sulfonamidic oxygen atoms [bond distances of 2.761(4) Å—2.971(4) Å] are also considered to build an equatorial plane and the N1 and N1′ atoms [bond distance of 2.037(5) Å] occupy the apical positions. Compound 2 is a dinuclear complex in which the copper ions are bridged by four syn‐syn acetate ligands which are related by a symmetry centre located in the centre of the complex. Each copper atom presents a nearly octahedral coordination where the equatorial plane is formed by four oxygen atoms and an isoxazolic nitrogen atom and the second copper atom occupy the apical positions.  相似文献   

6.
Syntheses and Structures of the Titanium(III) Siloxanes [Ti(OSiPh3)3(thf)2] and [Ti(OSiPh3)3(py)2] The new titaniumtrioxysilanes [Ti(OSiPh3)3(thf)2] ( 1 ) and [Ti(OSiPh3)3(py)2] ( 2 ) have been obtained from the reaction of titaniumtrichloride with LiOSiPh3 in the presence of the corresponding bases tetrahydrofurane (thf) and pyridine (py). From the crystal structures of both compounds it is evident that the titanium atoms are in the centres of trigonal‐bipyramidal coordination figures, with the donor atoms in axial positions. The compounds 1 and 2 have slightly different structures (mean values: 1 : Ti‐O(Si) 1.897(9), Ti‐O(C) 2.136(8) Å; 2 : Ti‐O 1.902(9), Ti‐N2.252(8) Å) and have a single absorption band in the visible region of the UV‐spectrum. The exchange of the thf‐ligands in 1 by pyridine (in high molar excess) seems to be hindered as deduced from UV‐spectroscopy.  相似文献   

7.
Synthesis and Crystal Structure of [Li(thf)4]2[Bi4I14(thf)2], [Li(thf)4]4[Bi5I19], and (Ph4P)4[Bi6I22] Solutions of BiI3 in THF or methanol react with MI (M = Li, Na) to form polynuclear iodo complexes of bismuth. The syntheses and results of X-ray structure analyses of compounds [Li(thf)4]2[Bi4I14(thf)2], [Li(thf)4]4[Bi5I19], [Na(thf)6]4[Bi6I22] and (Ph4P)4[Bi6I22] are described. The anions of these compounds consist of edge-sharing BiI6 and BiI5(thf) octahedra. The Bi atoms lie in a plane and are coordinated by bridging and terminal I atoms and by THF ligands in a distorted octahedral fashion. [Li(thf)4]2[Bi4I14(thf)2]: Space group P1 (No. 2), a = 1 159.9(6), b = 1 364.6(7), c = 1 426.5(7) pm, α = 114.05(3), β = 90.01(3), γ = 100.62(3)°. [Li(thf)4]4[Bi5I19]: Space group P21/n (No. 14), a = 1 653.0(9), b = 4 350(4), c = 1 836.3(13) pm, β = 114.70(4)°. [Na(thf)6]4[Bi6I22]: Space group P21/n (No. 14), a = 1 636.4(3), b = 2 926.7(7), c = 1 845.8(4) pm, β = 111.42(2)°. (Ph4P)4[Bi6I22]: Space group P1 (No. 2), a = 1 368.6(7), b = 1 508.1(9), c = 1 684.9(8) pm, α = 98.28(4), β = 95.13(4), γ = 109.48(4)°.  相似文献   

8.
Synthesis and structure of a Molybdenum–Gadolinium Heterometallic Complex. The Structure of [Li(thf)4]2[Cp2MoSGdBr4(thf)]2 [Cp2MoHLi] reacts in THF with S and GdBr3 to yield the tetranuclear heterobimetallic complex [Li(thf)4]2[Cp2MoSGdBr4(thf)]2. The bonding situation and the structure of this compound were characterized by X-ray structure analysis (space group P1 (No. 2), Z = 1, a = 10.845(2) Å, b = 12.166(2) Å, c = 15.881(2) Å, α = 101.74(2)°, β = 97.62(2)°, γ = 103.97(2)°). Each S atom of the central Mo2S2-ring is coordinated by a GdBr4(thf) fragment. Additionally each Mo atom is connected to two Cp ligands. This leads to a tetrahedral coordination of the Mo atoms and a octahedral coordination of the Gd ions.  相似文献   

9.
Syntheses and NMR Spectroscopic Ivestigations of Salts containing the Novel Anions [PtXn(CF3)6‐n]2— (n = 0 ‐ 5, X = F, OH, Cl, CN) and Crystal Structure of K2[(CF3)2F2Pt(μ‐OH)2PtF2(CF3)2]·2H2O The first syntheses of trifluoromethyl‐complexes of platinum through fluorination of cyanoplatinates are reported. The fluorination of tetracyanoplatinates(II), K2[Pt(CN)4], and hexacyanoplatinates(IV), K2[Pt(CN)6], with ClF in anhydrous HF leads after working up of the products to K2[(CF3)2F2Pt(μ‐OH)2PtF2(CF3)2]·2H2O. The structure of the salt is determined by a X‐ray structure analysis, P21/c (Nr. 14), a = 11.391(2), b = 11.565(2), c = 13.391(3)Å, β = 90.32(3)°, Z = 4, R1 = 0.0326 (I > 2σ(I)). The reaction of [Bu4N]2[Pt(CN)4] with ClF in CH2Cl2 generates mainly cis‐[Bu4N]2[PtCl2(CF3)4] and fac‐[Bu4N]2[PtCl3(CF3)3], but in contrast that of [Bu4N]2[Pt(CN)6] with ClF in CH2Cl2 results cis‐[Bu4N]2[PtX2(CF3)4], [Bu4N]2[PtX(CF3)5] (X = F, Cl) and [Bu4N]2[Pt(CF3)6]. In the products [Bu4N]2[PtXn(CF3)6‐n] (X = F, Cl, n = 0—3) it is possibel to exchange the fluoro‐ligands into chloro‐ and cyano‐ligands by treatment with (CH3)3SiCl und (CH3)3SiCN at 50 °C. With continuing warming the trifluoromethyl‐ligands are exchanged by chloro‐ and cyano‐ligands, while as intermediates CF2Cl and CF2CN ligands are formed. The identity of the new trifluoromethyl‐platinates is proved by 195Pt‐ and 19F‐NMR‐spectroscopy.  相似文献   

10.
Syntheses and Structures of the Phosphorus and Nitrogenbridged Transition Metal Complexes [Pd(NPhPPh2)(PPh3)]2, [Pd(NPhPPh2)2 · Li(thf)]2, [Pd(NPhPPh2)Cl · Li(thf)3]2, [M(NPhPPh2)(HNPhPPh2)]2 (M?Pd, Pt), [M{Ph2P(NPh)2}2] (M?Co, Ni), [Ni(PPh2){Ph2P(NPh)2}]2 and [Ni2(PPh2)(NPhPPh2)(HNPhPPh2)3] . From the reaction of LiNPhPPh2 with Palladium-Nickel- and Cobaltcomplexes, depending on the reaction conditions, different monomeric and dimeric complexes can be isolated. In these compounds the (NPhPPh2)?-group acts as both a bridging and as a terminal ligand. [Pd(NPhPPh2)(PPh3)]2 ( 1 ), [Pd(NPhPPh2)2 · Li(thf)]2 ( 2 ) and [Pd(NPhPPh2)Cl · Li(thf)3]2 ( 3 ) are formed from the reaction of [PdCl2(PPh3)2] or [PdCl2(COD)] with LiNPhPPh2. In contrast to this from the reaction of Pd(Ac)2 and HNPhPPh2 (in the presence of zinc-dust) or [PtCl2(py)2] and LiNPhPPh2.  相似文献   

11.
New reactive, divalent lanthanoid formamidinates [Yb(Form)2(thf)2] (Form=[RNCHNR]; R=o‐MeC6H4 (o‐TolForm; 1 ), 2,6‐Me2C6H3 (XylForm; 2 ), 2,4,6‐Me3C6H2 (MesForm; 3 ), 2,6‐Et2C6H3 (EtForm; 4 ), o‐PhC6H4 (o‐PhPhForm; 5 ), 2,6‐iPr2C6H3 (DippForm; 6 ), o‐HC6F4 (TFForm; 7 )) and [Eu(DippForm)2(thf)2] ( 8 ) have been prepared by redox transmetallation/protolysis reactions between an excess of a lanthanoid metal, Hg(C6F5)2 and the corresponding formamidine (HForm). X‐ray crystal structures of 2 – 6 and 8 show them to be monomeric with six‐coordinate lanthanoid atoms, chelating N,N′‐Form ligands and cis‐thf donors. However, [Yb(TFForm)2(thf)2] ( 7 ) crystallizes from THF as [Yb(TFForm)2(thf)3] ( 7 a ), in which ytterbium is seven coordinate and the thf ligands are “pseudo‐meridional”. Representative complexes undergo C? X (X=F, Cl, Br) activation reactions with perfluorodecalin, hexachloroethane or 1,2‐dichloroethane, and 1‐bromo‐2,3,4,5‐tetrafluorobenzene, giving [Yb(EtForm)2F]2 ( 9) , [Yb(o‐PhPhForm)2F]2 ( 10) , [Yb(o‐PhPhForm)2Cl(thf)2] ( 11) , [Yb(DippForm)2Cl(thf)] ( 12) and [Yb(DippForm)2Br(thf)] ( 16) . X‐ray crystallography has shown 9 to be a six‐coordinate, fluoride‐bridged dimer, 12 and 16 to be six‐coordinate monomers with the halide and thf ligands cis to each other, and 11 to have a seven‐coordinate Yb atom with “pseudo‐meridional” unidentate ligands and thf donors cis to each other. The analogous terbium compound [Tb(DippForm)2Cl(thf)2] ( 13 ), prepared by metathesis, has a similar structure to 11 . C? Br activation also accompanies the redox transmetallation/protolysis reactions between La, Nd or Yb metals, Hg(2‐BrC6F4)2, and HDippForm, yielding [Ln(DippForm)2Br(thf)] complexes (Ln=La ( 14 ), Nd ( 15 ), Yb ( 16 )).  相似文献   

12.
Single crystals of [Fe(Cp)2]3(Bi2Cl9)·thf were obtained from a thf solution containing ferrocene and BiCl3. The structure shows disorder at room temperature which disappears upon cooling, coupled with a decrease in symmetry. The title compound crystallizes in the orthorhombic space group P212121 [a = 1698.64(2), b = 2318.69(3), c = 1085.66(2) pm] with three ferrocenium ions, one nonachlorodibismutate ion and one molecule of thf in the asymmetric unit.  相似文献   

13.
The reaction of MCl4(thf)2 (M = Zr, Hf) with 1,4-dilitiobutane in diethyl ether at –25 °C or at 0 °C with a molar ratio of 1 : 3 yields the homoleptic “ate” complexes [(thf)4Li] [{(thf)Li}M(C4H8)3] 1 - Zr (M = Zr) and 1 - Hf (M = Hf). The crystalline compounds form ion lattices with solvent-separated [(thf)4Li]+ cations and [{(thf)Li}M(C4H8)3] anions. The NMR spectra at –20 °C show magnetic equivalence of the M–CH2 and of the β-CH2 groups of the butane-1,4-diide ligands on the NMR time scale. Analogous reactions of MCl4(thf)2 with 1,4-dilithiobutane with a molar ratio of 1 : 2 proceed unclear. However, single crystals of [Li(thf)4] [HfCl5(thf)] ( 2 ) can be isolated with the hafnium atom in a distorted octahedral coordination sphere of five chloro and one thf ligand. NMR spectra allow to elucidate the time-dependent degradation of 1-Hf and 1-Zr in THF and toluene at 25 °C via THF cleavage. Addition of tmeda to a solution of 1-Zr allows the isolation of intermediately formed [{(tmeda)Li}2Zr(nBu)2(C4H8)2] ( 3 ).  相似文献   

14.
Novel Synthesis of a Lanthanide Trialkyl – Characterization and Crystal Structure of Yb(CH2 t Bu)3(thf)2 The solvated ytterbium alkyl Yb(CH2tBu)3(thf)2 ( 1 ) was obtained in moderate yield from the reaction of ytterbium metal with neopentyl iodide. Ruby‐red air‐sensitive crystals of 1 were characterized by melting point, elemental analysis, IR, NMR, and UV/Vis spectroscopy and by X‐ray crystallography. In the solid state the ytterbium atom shows a trigonal bipyramidal coordination with the neopentyl groups and the THF ligands occupying equatorial and axial positions, respectively.  相似文献   

15.
Synthesis, Crystal Structure, and Thermal Decomposition of Mg(H2O)6[B12H12] · 6 H2O By reaction of an aqueous solution of the free acid (H3O)2[B12H12] with MgCO3 and subsequent isothermic evaporation of the resulting solution to dryness, colourless, bead‐shaped single crystals of the dodecahydrate of magnesium dodecahydro closo‐dodecaborate Mg(H2O)6[B12H12] · 6 H2O (cubic, F4132; a = 1643.21(9) pm, Z = 8) emerge. The crystal structure is best described as a NaTl‐type arrangement in which the centers of gravity of the quasi‐icosahedral [B12H12]2— anions (d(B—B) = 178—180 pm, d(B—H) = 109 pm) occupy the positions of Tl while the Mg2+ cations occupy the Na+ positions. A direct coordinative influence of the [B12H12]2— units at the Mg2+ cations is however not noticeable. The latter are octahedrally coordinated by six water molecules forming isolated hexaaqua complex cations [Mg(H2O)6]2+ (d(Mg—O) = 206 pm, 6×). In addition, six “zeolitic” water molecules are located in the crystal structure for the formation of a strong O—Hδ+···δ—O‐hydrogen bridge‐bonding system. The evidence of weak B—Hδ—···δ+H—O‐hydrogen bonds between water molecules and anionic [B12H12]2— clusters is also considered. Investigations on the dodecahydrate Mg[B12H12] · 12 H2O (≡ Mg(H2O)6[B12H12] · 6 H2O) by DTA/TG measurements showed that its dehydration takes place in two steps within a temperature range of 71 and 76 °C as well as at 202 °C, respectively. Thermal treatment eventually leads to the anhydrous magnesium dodecahydro closo‐dodecaborate Mg[B12H12].  相似文献   

16.
Syntheses and Crystal Structures of the Nitrido‐chloro‐molybdates [Mg(THF)4{NMoCl4(THF)}2] · 4 CH2Cl2 and [Li(12‐Crown‐4)(NMoCl4)]2 · 2 CH2Cl2 Both the title compounds as well as [Li(12‐crown‐4)2]+MoNCl4 were made from MoNCl3 and the chlorides MgCl2 and LiCl, respectively, in dichloromethane suspensions in the presence of tetrahydrofuran and 12‐crown‐4, respectively. They form orange‐red moisture‐sensitive crystals, which were characterized by their IR spectra and partly by crystal structure analyses. [Mg(THF)4{NMoCl4(THF)}2] · 4 CH2Cl2 ( 1 ): space group C2/m, Z = 2, lattice dimensions at –50 °C: a = 1736.6(1), b = 1194.8(1), c = 1293.5(2) pm; β = 90.87(1)°; R1 = 0.037. In 1 the magnesium ion is coordinated octahedrally by the oxygen atoms of the four THF molecules and in trans‐position by the nitrogen atoms of the two [N≡MoCl4(THF)] ions. [Li(12‐crown‐4)(NMoCl4)]2 · 2 CH2Cl2 ( 2 ): space group P 1, Z = 1, lattice dimensions at –70 °C: a = 930.4(1), b = 957.9(1), c = 1264.6(1) pm; α = 68.91(1)°, β = 81.38(1)°, γ = 63.84(1)°; R1 = 0.0643. 2 forms a centrosymmetric ion ensemble in the dimeric cation of which, i. e. [Li(12‐crown‐4)]22+, the lithium ions on the one hand are connected to the four oxygen atoms each of the crown ether molecules in a way not yet known; and in addition, each of the lithium ions enters into a intermolecular Li–O bond with neighboring crown ether molecules under formation of a Li2O2 four‐membered ring. The two N≡MoCl4 counterions are loosely coordinated to one oxygen atom each of the crown ether molecules with Mo–O distances of 320.2 pm.  相似文献   

17.
Crystal Structures of the Phosphaneimine Complexes [NaI(HNPPh3)3] and [SrI2(HNPPh3)2(THF)2], as well as of Sodium Triphenylphosphoraneiminate [NaNPPh3]6 [NaI(HNPPh3)3] ( 1 ) has been obtained as yellow, moisture sensitive crystals as an intermediate product of the synthesis of sodium triphenylphosphoraneiminate, [NaNPPh3]6 ( 2 ) from Ph3PI2 and sodium amide in liquid ammonia. Correspondingly, colourless crystals of [SrI2(HNPPh3)2(THF)2] ( 3 ) are formed from strontium amide and Ph3PI2 in liquid ammonia and subsequent recrystallisation of the primary product [SrI2(HNPPh3)4] from thf solution. The complexes 1 – 3 are mainly characterized by crystal structure determinations. 1 · 0,5 thf: space group P3c1, Z = 4, lattice dimensions at 193 K: a = b = 1533.2(1); c = 2545.6(1) pm, R = 0.0417. 1 has a molecular structure in which the sodium atom is tetrahedrally coordinated by the iodine atom with a distance of 315.9 pm and by the nitrogen atoms of the three HNPPh3 molecules with a distance of 238.9 pm. 2 · C7H8: space group P1, Z = 1, lattice dimensions at 213 K: a = 1457.1(1), b = 1484.9(1), c = 1502.7(1) pm; α = 116.32(1)°, β = 115.358(10)°, γ = 93.585(14)°; R = 0.0520. 2 has a molecular structure in which the six sodium atoms and the six nitrogen atoms of the (NPPh3) groups form a hexagonal prism with approximate D3d symmetry. 3 · 2 thf: space group P1, Z = 2, lattice dimensions at 193 K: a = 1042.9(1), b = 1337.4(1), c = 2095.1(1) pm; α = 90.130(8)°, β = 96.310(8)°, γ = 111.985(8)°; R = 0.0310. 3 has a molecular structure in which the strontium atom is octahedrally coordinated by the iodine atoms, by the nitrogen atoms of the HNPPh3 molecules and by the oxygen atoms of the thf molecules, all ligands being in trans‐position to one another.  相似文献   

18.
CrCl3(thf)3 is a common starting material in the synthesis of organometallic and coordination compounds of Cr. Deposited as an irregular solid with no possibility of recrystallization, it is not a purity guaranteed chemical, causing problems in some cases. In this work, we disclose a well-defined form of the THF adduct of CrCl3 ([CrCl2(μ-Cl)(thf)2]2), a crystalline solid, that enables structure determination by X-ray crystallography. The EA data and XRD pattern of the bulk agreed with the revealed structure. Moreover, its preparation procedure is facile: evacuation of CrCl3·6H2O at 100 °C, treatment with 6 equivalents of Me3SiCl in a minimal amount of THF, and crystallization from CH2Cl2. The ethylene tetramerization catalyst [iPrN{P(C6H4-p-Si(nBu)3)2}2CrCl2]+[B(C6F5)4] prepared using well-defined [CrCl2(μ-Cl)(thf)2]2 as a starting material exhibited a reliably high activity (6600 kg/g-Cr/h; 1-octene selectivity at 40 °C, 75%), while that of the one prepared using the impure CrCl3(thf)3 was inconsistent and relatively low (~3000 kg/g-Cr/h). By using well-defined [CrCl2(μ-Cl)(thf)2]2 as a Cr source, single crystals of [(CH3CN)4CrCl2]+[B(C6F5)4] and [{Et(Cl)Al(N(iPr)2)2}Cr(μ-Cl)]2 were obtained, allowing structure determination by X-ray crystallography, which had been unsuccessful when the previously known CrCl3(thf)3 was used as the Cr source.  相似文献   

19.
The reaction of [1,3‐bis(2‐ethoxy)benzene]triazene, [ HL ], with Hg(SCN)2 and Hg(CH3COO)2, resulted in the formation of the complexes [Hg L (SCN)] ( 1 ) and [Hg L 2] · CH3OH ( 2 ). They were characterized by means of X‐ray crystallography, CHN analysis, FT‐IR, 1H NMR, and 13C NMR spectroscopy. The structure of compound 1 consists of two independent complexes in which the HgII atoms are stacked along the crystallographic a axis to form infinite chains. Each HgII atom is chelated by one L ligand and one SCN ligand, whereas in compound 2 , the HgII atom is surrounded by two L ligands. In addition, 1D chains formed by metal–π interactions are connected to each other by C–H ··· π stacking interactions in the structure of 1 , which results in a 2D architecture. An interesting feature of compound 2 is the presence of C–H ··· π edge‐to‐face interactions.  相似文献   

20.
The reactions of [Co2(CO)8] with E(SiMe3)2 (E = Se, Te) in CH2Cl2 result in the formation of the compounds [Co4Se2(CO)10]> ( 1 ) and [Co4Te2(CO)11] ( 2 ), respectively. Both cluster complexes have similar molecular structures in which the cobalt atoms form four‐membered rings with μ4‐bridging chalcogen atoms (Se and Te) above and below the plane of the metal atoms and the carbonyl ligands as either terminal or μ2‐bridging ligands. DFT‐calculations for both compounds have been carried out in order to obtain some more information about their electronic distribution. In the presence of the phosphine Ph2PC≡CPPh2 (dppa), the reaction of [Co2(CO)8] with Se(SiMe3)2 leads to the formation of [Co8Se4(CO)16(μ‐dppa)2] ( 3 ). During the reaction two molecules of [Co2(CO)8] have been added to the acetylene groups of the dppa ligands, whilst the remaining cobalt atoms coordinate to the phosphorus atoms of the phosphine. In this compounds the selenium atoms act as μ3‐ligands, bridging the metal atoms bonded to the phosphorus with those bonded to the acetylene groups.  相似文献   

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