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Tetrakis(trimethylsilyl)silane
Tetrakis(trimethylsilyl)silane is the organosilicon compound with the formula (Me3Si)4Si (where Me = CH3). It is a colorless sublimable solid with a high melting point. The molecule has tetrahedral symmetry. The compound is notable as having silicon bonded to four other silicon atoms, like in elemental silicon. Preparation and reactions The compound is prepared by the reaction of trimethylsilyl chloride, silicon tetrachloride, and lithium: :4 Me3SiCl + SiCl4 + 8 Li → (Me3Si)4Si + 8 LiCl The compound is a precursor to tris(trimethylsilyl)silyl lithium by reaction with methyl lithium:{{cite journal, title=Tris(trimethylsilyl)silane, author=Joachim Dickhaut, Bernd Giese, journal=Org. Synth., year=1992, volume=70, page=164, doi=10.15227/orgsyn.070.0164 :(Me3Si)4Si + MeLi → (Me3Si)3SiLi + Me4Si The organolithium compound (Me3Si)3SiLi is a versatile reagent, e.g. to tris(trimethylsilyl)silane ((Me3Si)3SiH). See also * Tris(trimethylsilyl)methane Tris(trimethy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organosilicon Compound
Organosilicon compounds are organometallic compounds containing carbon–silicon bonds. Organosilicon chemistry is the corresponding science of their preparation and properties. Most organosilicon compounds are similar to the ordinary organic compounds, being colourless, flammable, hydrophobic, and stable to air. Silicon carbide is an ''inorganic'' compound. History In 1846 Von Ebelman's had synthesized Tetraethyl orthosilicate (Si(OC2H5)4). In 1863 Friedel and Crafts managed to make the first organosilieon compound with C-Si bonds which gone byound the syntheses of orthosilicic acid esters. The same year they also described a «polysilicic acid ether» in the preparation of ethyl- and methyl-o-silicic acid. The early extensive research in the field of organosilicon compounds was pioneerd in the beginning of 20th century by Frederic Kipping. He also had coined the term «silicone» (akin to ketones) in relation to these materials in 1904. In recognition of Kipping's achiev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimethylsilyl Chloride
Trimethylsilyl chloride, also known as chlorotrimethylsilane is an organosilicon compound (silyl halide), with the formula (CH3)3SiCl, often abbreviated Me3SiCl or TMSCl. It is a colourless volatile liquid that is stable in the absence of water. It is widely used in organic chemistry. Preparation TMSCl is prepared on a large scale by the ''direct process'', the reaction of methyl chloride with a silicon-copper alloy. The principal target of this process is dimethyldichlorosilane, but substantial amounts of the trimethyl and monomethyl products are also obtained. The relevant reactions are (Me = CH3): : x MeCl + Si → Me3SiCl, Me2SiCl2, MeSiCl3, other products Typically about 2–4% of the product stream is the monochloride, which forms an azeotrope with MeSiCl3. Reactions and uses TMSCl is reactive toward nucleophiles, resulting in the replacement of the chloride. In a characteristic reaction of TMSCl, the nucleophile is water, resulting in hydrolysis to give the hexameth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicon Tetrachloride
Silicon tetrachloride or tetrachlorosilane is the inorganic compound with the formula SiCl4. It is a colourless volatile liquid that fumes in air. It is used to produce high purity silicon and silica for commercial applications. Preparation Silicon tetrachloride is prepared by the chlorination of various silicon compounds such as ferrosilicon, silicon carbide, or mixtures of silicon dioxide and carbon. The ferrosilicon route is most common. In the laboratory, can be prepared by treating silicon with chlorine at : : It was first prepared by Jöns Jakob Berzelius in 1823. Brine can be contaminated with silica when the production of chlorine is a byproduct of a metal refining process from metal chloride ore. In rare occurrences, the silicon dioxide in silica is converted to silicon tetrachloride when the contaminated brine is electrolyzed. Reactions Hydrolysis and related reactions Like other chlorosilanes, silicon tetrachloride reacts readily with water: :SiCl4 + 2 H2O → ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Lithium
Methyllithium is the simplest organolithium reagent with the empirical formula CH3Li. This s-block organometallic compound adopts an oligomeric structure both in solution and in the solid state. This highly reactive compound, invariably used in solution with an ether as the solvent, is a reagent in organic synthesis as well as organometallic chemistry. Operations involving methyllithium require anhydrous conditions, because the compound is highly reactive toward water. Oxygen and carbon dioxide are also incompatible with MeLi. Methyllithium is usually not prepared, but purchased as a solution in various ethers. Synthesis In the direct synthesis, methyl bromide is treated with a suspension of lithium in diethyl ether. :2 Li + MeBr → LiMe + LiBr The lithium bromide forms a complex with the methyllithium. Most commercially available methyllithium consists of this complex. "Halide-free" methyllithium is prepared from methyl chloride. Lithium chloride precipitates fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tris(trimethylsilyl)silane
Tris(trimethylsilyl)silane is the organosilicon compound with the formula (Me3Si)3SiH (where Me = CH3). It is a colorless liquid that is classified as a hydrosilane since it contains an Si-H bond. The compound is notable as having a weak Si-H bond, with a bond dissociation energy estimated at 84 kcal/mol. For comparison, the Si-H bond in trimethylsilane is 94 kcal/mol. With such a weak bond, the compound is used as a reagent to deliver hydrogen atoms. The compound has been described as an environmentally benign analogue of tributyltin hydride Tributyltin hydride is an organotin compound with the formula (C4H9)3SnH. It is a colorless liquid that is soluble in organic solvents. The compound is used as a source of hydrogen atoms in organic synthesis. Synthesis and characterization The .... The compound can be prepared by protonation of tris(trimethylsilyl)silyl lithium, which is derived from tetrakis(trimethylsilyl)silane: :(Me3Si)4Si + MeLi → (Me3Si)3SiLi + Me4Si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tris(trimethylsilyl)methane
Tris(trimethylsilyl)methane is the organosilicon compound with the formula (tms)3CH (where tms = (CH3)3Si). It is a colorless liquid that is highly soluble in hydrocarbon solvents. Reaction of tris(trimethylsilyl)methane with methyl lithium gives tris(trimethylsilyl)methyllithium, called trisyllithium. Trisyllithium is useful in Petersen olefination reactions: :(tms)3CH + CH3Li → (tms)3CLi + CH4 :(tms)3CLi + R2CO → (tms)2C=CR2 + tmsOLi Trisyllithium is also an effective precursor to bulky ligands. Some tris(trimethylsilyl)methyl derivatives are far more stable than less substituted derivatives. for example is a well-behaved tellurol. See also * Tris(trimethylsilyl)silane Tris(trimethylsilyl)silane is the organosilicon compound with the formula (Me3Si)3SiH (where Me = CH3). It is a colorless liquid that is classified as a hydrosilane since it contains an Si-H bond. The compound is notable as having a weak Si-H bo ... References Carbosilanes Tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbosilanes
Carbosilanes are organosilicon compounds where the structures feature alternating silicon and carbon atoms, i.e., Si-C-Si-C linkages. They represent molecular analogues of silicon carbide. The compounds exploit the tendency of both carbon and silicon to form tetrahedral structures. The inventory of carbosilanes is large.{{cite book , doi=10.1007/978-3-642-70800-8, title=Carbosilanes , year=1986 , last1=Fritz , first1=Gerhard , last2=Matern , first2=Eberhard , isbn=978-3-642-70802-2 Synthesis and structure The compounds originally were obtained as products of the pyrolysis of simple organosilicon precursors such as the methylsilane Methylsilane is the organosilicon compound with the formula . It is a colorless gas that ignites in air. It can be prepared by reduction of methyltrichlorosilane with lithium aluminium hydride. It has been investigated as a precursor to silicon ...s. More efficient precursors contain premade Si-C-Si-C etc. subunits. References Carbosilanes [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
