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651.
Brendan Twamley PhilipP. Power 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2000,112(19):3643-3646
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653.
Werner Uhl Lars Cuypers Kristiane Schüler Thomas Spies Carsten Strohmann Klaus Lehmen 《无机化学与普通化学杂志》2000,626(7):1526-1534
Bridging Coordination of Gallium–Gallium Bonds by Chelating Ligands – Limitations of the Stability of Digallium Derivatives The reactions of bis[bis(trimethylsilyl)methyl]‐di(μ‐acetato)digallium(Ga–Ga) ( 2 ) with lithium‐2‐amido‐1‐methylbenzimidazole in the molar ratios of 1 to 1 or 1 to 2 yielded by the precipitation of lithium aceatate new digallium compounds, in which the intact Ga–Ga bonds were bridged by two chelating ligands. The replacement of only one acetato group gave compound 5 , that possesses two different bridging ligands with the benzimidazole group coordinated by its terminal amido function and that nitrogen atom of the heterocycle which is not attached to a methyl group. If both acetato groups were replaced by imdazole ligands, two products were obtained, in which the chelates are transferred in each other either by a mirror plane parallel to the Ga–Ga bond (cis, 6 ) or by a twofold rotational axis perpendicular to the element–element bond (trans, 7 ). 7 is thermodynamically favored and was irreversibly formed by heating of the mixture. 5 and 7 were characterized by crystal structure determinations and have Ga atoms in a chiral environment. Weaker donor ligands such as diphenyl(lithiomethyl)(piperidinomethyl)silane, which in principal is able to coordinate via its carbanionic carbon atom and more weakly via its sterically shielded piperidino nitrogen atom, led to the cleavage of the Ga–Ga bond. The mononuclear compound 8 was isolated, in which the Ga atom is attached to one bis(trimethylsilyl)methyl group and two (piperidinomethyl)silyl substituents. Furthermore, the synthesis of a dialkyl‐bis(1,3‐dionato)digallium derivative ( 9 ) is reported, in which the chelating 1,3‐dionato groups are terminally coordinated to the Ga atoms of the unsupported Ga–Ga bond. 相似文献
654.
Elmar Hecht 《无机化学与普通化学杂志》2000,626(7):1642-1646
Preparation, Properties, and Molecular Structures of Dimethylmetal Alkoxides and Amides of Aluminium and Gallium Dimethylaluminium‐ ( 1 ) and Dimethylgallium‐o‐methoxyphenyl‐1‐ethoxide ( 2 ) were obtained by reaction of Me3Al and Me3Ga respectively with o‐Methoxyphenyl‐1‐ethanol in n‐pentane. Dimethylaluminium‐ ( 3 ) and dimethylgallium‐o‐methoxyphenyl‐2‐ethylamide ( 4 ) were prepared by treatment of Me2AlCl and Me2GaCl respectively with Lithium‐o‐methoxyphenyl‐2‐ethylamide. Trimethylgallium‐o‐methoxyphenylmethylamine‐Adduct ( 5 ) was isolated using reaction of Me3Ga with the corresponding amine. The compounds were characterised by 1H‐, 13C‐, and 27Al n.m.r. spectroscopy. The molecular structures of 2 and 5 were determined by X‐ray diffraction. Compounds 1 – 4 form brigded dimeric molecules. The bond distances of the central Ga2O2 ring in 2 correspond to those of compounds of similar structure. 相似文献
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Synthesis and X‐Ray Structure Determination of iso ‐Butylimido Galliummethyl, [CH3Ga–NCH2CH(CH3)2]6 The thermal decomposition of [Me2Ga–N(iBu)SnMe3]2 (prepared by the reaction of [Me2SnNiBu]3 with GaMe3 in a 1:3 molar ratio) in an evacuated, sealed tube at 160°C forms [MeGaNiBu]6 in high yield and SnMe4. Mass, 1H and 13C NMR as well as some IR and Raman spectroscopic data are given and the crystal structure of this cage molecule with a hexagonal prismatic Ga6N6 skeleton has been determined. 相似文献
658.
Andreas Schnepf Gregor Stßer Duncan Carmichael Franois Mathey Hansgeorg Schnckel 《Angewandte Chemie (International ed. in English)》1999,38(11):1646-1649
Monomeric polyhapto-bound phospholyl compounds were hitherto unknown for the main group elements. Use of a solution of metastable GaBr has allowed the synthesis of monomeric η5-phospholylgallium, which has been characterized by X-ray structure analysis as the Cr(CO)5 complex 1 . 相似文献
659.
Takehiko Iida Noriyoshi Yamamoto Shigeki Matsunaga Hee-Gweon Woo Masakatsu Shibasaki 《Angewandte Chemie (International ed. in English)》1998,37(16):2223-2226
Useful chiral building blocks such as 1,2-diols can be obtained by the enantioselective ring opening of achiral epoxides with oxygen nucleophiles. The ring opening is carried out effectively (up to 94 % ee) with 4-methoxyphenol and catalytic amounts of gallium complexes. The novel complex GaSO 1 displays a particularly high catalytic activity. 相似文献
660.
用电弧熔炼法合成了系列化合物REGaSi,采用粉末X射线衍射方法测定了化合物SmGaSi的晶体结构,获得其晶体学及结构修正参数为;四方晶系,LaPtSi类型,(109)I41md,Mr=250.0,a=0.4134(3)nm,c=1.422(2)nm,V=0.2430(5)nm^3,Z=4,Dx=6.464g.cm^-3,F(000)=428,T=296K。 相似文献