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121.
122.
The Variable Reaction Behaviour of Base‐free Tris(trimethylsilyl)methyl Lithium with Trihalogenides of Earth‐Metals and Iron Base‐free tris(trimethylsilyl)methyl Lithium, Tsi–Li, reacts with the earth‐metal trihalogenides (MHal3 with M = Al, Ga, In and Hal = Cl, Br, I) primarily to give the metallates [Tsi–MHal3]Li. Simultaneous to this simple metathesis a methylation also takes place, mainly with heavier halogenides of Ga and In with excess Tsi–Li, forming the mono and dimethyl compounds Tsi–M(Me)Hal (M = Ga, In; Hal = I), Tsi–MMe2 (M = Ga), and the bis(trisyl)derivative (Tsi)2InMe, respectively and the main by‐product 1,3‐disilacyclobutane. Representatives of each type of compound have been isolated by fractionating crystallizations or sublimations and characterized by spectroscopic methods (1H, 13C, 29Si NMR, IR, Raman) and X‐ray elucidations. Reduction takes place, when FeCl3 reacts with Tsi–Li (1 : 3 ratio) in toluene at 55–60 °C, yielding red‐violet Fe(Tsi)2, 1,1,1‐tris(trimethylsilyl)‐2‐phenyl ethane and low amounts of Tsi–Cl. Fe(Tsi)2 is monomeric, crystallizes in the monoclinic space group C2/c and consists of a linear C–Fe–C skeleton with d(Fe–C) of 204,5(4) pm. 相似文献
123.
Syntheses of Compounds with M–N Bonds (M = Li, Ga, In) The adducts [GaCl3(HNiPr2)] ( 1 ) and [InCl3{HN(CH2Ph)2}2] ( 2 ) can be obtained by the reactions of the corresponding metal(III) halides with the amines. The In amide In(NcHex2)3 ( 3 ) can be formed by treatment of InCl3 with three equivalents of LiNcHex2. Reaction with four equivalents of LiNcHex2 leads to the same product. However, the treatment of InCl3 with four equivalents of LiN(CH2Ph)2 gives the desired metalate [Li(THF)4][In{N(CH2Ph)2}4] ( 4 ). From the corresponding reaction of InCl3 with LiNiPr2 no In‐containing product could be identified. Instead, the aggregate of LiCl with three units of LiNiPr2, [Li4(NiPr2)3(THF)4Cl] ( 5 ), was isolated. 1 – 4 were characterized by NMR, IR and MS techniques as well as by X‐ray structure determinations. According to them, 1 possesses a tetrahedrally coordinated Ga atom, at which two units of 1 are connected by hydrogen bridges to centrosymmetrical dimers. The In atoms in 2 have a trigonal‐bipyramidal coordination sphere; the amine molecules occupy the apical positions. The central metal atom in 3 and the anion of 4 exhibit trigonal‐planar and distorted tetrahedral environments, respectively. The novel structural motif in 5 is the Cl– ion, only partly surrounded by Li+ ions in a strongly distorted trigonal‐bipyramidal fashion. The dominating angle amounts to 165.2(2)°. 相似文献
124.
125.
[PtIn6][GaO4]2 – The First Oxide Containing [PtIn6] Octahedra. Preparation, Characterisation, and Rietveld Refinement – With a Remark to the Solid Solution Series [PtIn6][GaO4]2‐x[InO4]x (0 < x ≤ 1) The novel oxides [PtIn6][GaO4]2–x[InO4]x (0 < x ≤ 1) are formed by heating intimate mixtures of Pt, In, In2O3, and Ga2O3 in the corresponding stoichiometric ratio in corundum crucibles under an atmosphere of argon (1220 K, 70 h). The compounds are black, stable in air at room temperature, reveal a semiconducting behaviour, and decompose only in oxidizing acids. X‐ray powder diffraction patterns can be indexed by assuming a face centered cubic unit cell with lattice parameters ranging from a = 1001.3(1) pm (x = 0) to a = 1009.3(1) pm (x = 1). According to a Rietveld refinement [PtIn6][GaO4]2 crystallizes isotypic to the mineral Pentlandite (Fm3m, Z = 4, R(profile) = 6.11%, R(intensity) = 3.95%). The characteristic building units are isolated [PtIn6]10+ octahedra which are linked via [GaO4]5– tetrahedra to a three dimensional framework. Starting from [PtIn6][GaO4]2 the substitution of Ga3+ ions by larger In3+ ions leads to the formation of a solid solution series according to the general formula [PtIn6][GaO4]2–x[InO4]x and becomes apparent in an increase of the lattice parameter. 相似文献
126.
127.
The Crystal Structure of Ga5Pd13 – a Low‐Symmetrical Ordering Variant of the Cubic Close Sphere Packing Ga5Pd13 is accessible from the elements in the presence of catalytically active amounts of iodine at 520 °C. The phase decomposes at 897 °C in a peritectoid reaction. The monoclinic crystal structure was determined from the intensities of an X‐ray powder diffractogram and refined by a Rietveld profile fit: C 2/m, Z = 2, a = 2425.99(5) pm, b = 405.060(7) pm, c = 544.37(1) pm, β = 102.690(1)°, Rp = 0.069. The new structure type is described as an ordering variant of the cubic close sphere packing. The ordering pattern and the distortions in the primary coordination of the atoms reflect the definite impact of the intermetallic bonding interactions on the differentiation of the structure. 相似文献
128.
Stabilization of M+ Ions (M = In, Tl) by Dibenzyldichlorogallate MCl reacts with (PhCH2)2GaCl to give M[(PhCH2)2GaCl2] [M = In ( 1 ), Tl ( 2 )]. 1 and 2 were characterized by NMR, IR and MS techniques. In addition, an X‐ray structure determination of 1 was performed. According to this, 1 consists of four‐membered In2Cl2 rings connected by weak In…Cl contacts (344 pm) along [010] to a coordination polymer. The In+ ion is coordinated by four In–Cl and two In‐aryl interactions. 相似文献
129.
Two new non‐metallic filled β‐manganese phases M2Ga6Te10 (M: Li, Na) are obtained as black, homogeneous, microcristalline samples as well as single crystals by direct reaction of the elements. According to the single crystal structure determinations both compounds crystallize in space group R32 (No. 155, Z = 2) with the lattice constants: a = 1436.9(2), c = 1759.0(4) pm (T = 180 K, Li2Ga6Te10) and a = 1458(1) pm, c = 1776.1(4) pm (T = 290 K, Na2Ga6Te10). Their structures are characterized by tetrahedral close packings of Te2–, corresponding to the arrangement of Mn atoms in β‐Mn. While Ga3+ ions are distributed in an ordered way over 12% of the tetrahedral holes, the M+ ions occupy all distorted octahedral (“metaprismatic”) holes. As the Li+ ions are too small they occupy off‐center positions inside the metaprisms. Positions with the strongest off‐centering can only be refined on the basis of a split model. MAS‐NMR measurements, including multiple quantum NMR, allowed the two different crystallographic M+ sites to be distinguished unambigously by separate 7Li and 23Na signals, respectively. The assignment of the NMR signals was supported by measurements of samples in which Li+ was partly substituted by larger cations (Sn2+, Pb2+). 相似文献
130.
Elmar Hecht 《无机化学与普通化学杂志》2000,626(3):759-765
Preparation, Properties, and Molecular Structures of Dimethylaminomethyl Ferrocenyl Compounds of selected Elements of Group 13 and 14 Dimethylmetalchlorides of gallium and indium react with dimethylaminomethylferrocenyllithium (FcNLi) to give the corresponding dimethylmetaldimethylaminomethylferrocenes 1 and 2 [Me2MFcN; M=Ga, In]. In a similar manner dialkylmetaldichlorides of germanium and tin yield the expected chlordialkylmetaldimethylaminomethylferrocenes 3 – 5 [R2(Cl)MFcN; M=Ge; R = Me ( 3 ), M=Sn; R=Me ( 4 ), Ph ( 5 )]. In a reaction of Me3Al and Me2AlCl with dimethylaminomethylferrocene the formation of the 1 : 1 adducts 7 and 8 could be observed. All compounds were characterised by 1H and 13C nmr spectroscopy. The molecular structures of 1 , 3 , 4 and 7 were determined. 3 and 4 build in contrast to 1 monomeric molecules with chelat rings as a result of the M–N coordination. Compound 7 consist of monomeric molecules with 4 coordinated Al atoms. 相似文献