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Silanes
Silanes refers to diverse kinds of charge-neutral silicon compounds with the formula . The R substituents can any combination of organic or inorganic groups. Most silanes contain Si-C bonds, and are discussed under organosilicon compounds. Examples: *Silane , the parent. *Binary silicon-hydrogen compounds (which are sometimes called silanes also) includes silane itself but also compounds with Si-Si bonds including disilane and longer chains. *Silanes with one, two, three, or four Si-H bonds are called hydrosilanes. Silane itself is the parent member. Examples: triethylsilane () and triethoxysilane (). *Polysilanes are organosilicon compounds with the formula . They include all binary silicon-hydrogen compounds except the parent, although these tend to be less useful because they are fragile. Attracting more interest, are the organic derivatives such as polydimethylsilane and dodecamethylcyclohexasilane *Chlorosilanes have Si-Cl bonds. Examples: trichlorosilane () and tetrachlo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Silicon-hydrogen Compounds
Silanes are saturated chemical compounds with the empirical formula SixHy. They are hydrosilanes, a class of compounds that includes compounds with Si-H and other Si-X bonds. All contain tetrahedral silicon and terminal hydrides. They only have Si–H and Si–Si single bonds. The bond lengths are 146.0 pm for a Si–H bond and 233 pm for a Si–Si bond. The structures of the silanes are analogues of the alkanes, starting with silane, , the analogue of methane, continuing with disilane , the analogue of ethane, etc. They are mainly of theoretical or academic interest. Inventory 132px, Cyclopentasilane is structurally similar to cyclopentane, just larger.">cyclopentane.html" ;"title="Cyclopentasilane is structurally similar to cyclopentane">Cyclopentasilane is structurally similar to cyclopentane, just larger. The simplest isomer of a silane is the one in which the silicon atoms are arranged in a single chain with no branches. This isomer is sometimes called the ''n'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Silicon-hydrogen Compounds
Silanes are saturated chemical compounds with the empirical formula SixHy. They are hydrosilanes, a class of compounds that includes compounds with Si-H and other Si-X bonds. All contain tetrahedral silicon and terminal hydrides. They only have Si–H and Si–Si single bonds. The bond lengths are 146.0 pm for a Si–H bond and 233 pm for a Si–Si bond. The structures of the silanes are analogues of the alkanes, starting with silane, , the analogue of methane, continuing with disilane , the analogue of ethane, etc. They are mainly of theoretical or academic interest. Inventory 132px, Cyclopentasilane is structurally similar to cyclopentane, just larger.">cyclopentane.html" ;"title="Cyclopentasilane is structurally similar to cyclopentane">Cyclopentasilane is structurally similar to cyclopentane, just larger. The simplest isomer of a silane is the one in which the silicon atoms are arranged in a single chain with no branches. This isomer is sometimes called the ''n'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disilane
Disilane is a chemical compound with chemical formula Si2H6 that was identified in 1902 by Henri Moissan and Samuel Smiles (1877–1953). Moissan and Smiles reported disilane as being among the products formed by the action of dilute acids on metal silicides. Although these reactions had been previously investigated by Friedrich Woehler and Heinrich Buff between 1857 and 1858, Moissan and Smiles were the first to explicitly identify disilane. They referred to disilane as ''silicoethane''. Higher members of the homologous series SinH2n+2 formed in these reactions were subsequently identified by Carl Somiesky (sometimes spelled "Karl Somieski") and Alfred Stock. At standard temperature and pressure, disilane is a colourless, acrid gas. Disilane and ethane have similar structures, although disilane is much more reactive. Other compounds of the general formula Si2X6 (X = hydride, halide, alkyl, aryl, and mixtures of these groups) are called disilanes. Disilane is a group 14 hydrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silanes
Silanes refers to diverse kinds of charge-neutral silicon compounds with the formula . The R substituents can any combination of organic or inorganic groups. Most silanes contain Si-C bonds, and are discussed under organosilicon compounds. Examples: *Silane , the parent. *Binary silicon-hydrogen compounds (which are sometimes called silanes also) includes silane itself but also compounds with Si-Si bonds including disilane and longer chains. *Silanes with one, two, three, or four Si-H bonds are called hydrosilanes. Silane itself is the parent member. Examples: triethylsilane () and triethoxysilane (). *Polysilanes are organosilicon compounds with the formula . They include all binary silicon-hydrogen compounds except the parent, although these tend to be less useful because they are fragile. Attracting more interest, are the organic derivatives such as polydimethylsilane and dodecamethylcyclohexasilane *Chlorosilanes have Si-Cl bonds. Examples: trichlorosilane () and tetrachlo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silane
Silane is an inorganic compound with chemical formula, . It is a colourless, pyrophoric, toxic gas with a sharp, repulsive smell, somewhat similar to that of acetic acid. Silane is of practical interest as a precursor to elemental silicon. Silane with alkyl groups are effective water repellents for mineral surfaces such as concrete and masonry. Silanes with both organic and inorganic attachments are used as coupling agents. Production Commercial-scale routes Silane can be produced by several routes. Typically, it arises from the reaction of hydrogen chloride with magnesium silicide: : Mg2Si + 4 HCl -> 2 MgCl2 + SiH4 It is also prepared from metallurgical-grade silicon in a two-step process. First, silicon is treated with hydrogen chloride at about 300 °C to produce trichlorosilane, HSiCl3, along with hydrogen gas, according to the chemical equation : Si + 3 HCl -> HSiCl3 + H2 The trichlorosilane is then converted to a mixture of silane and silicon tetrachloride: : 4 HS ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrosilane
Hydrosilanes are tetravalent silicon compounds containing one or more Si-H bond. The parent hydrosilane is silane (SiH4). Commonly, hydrosilane refers to organosilicon derivatives. Examples include phenylsilane (PhSiH3) and triethoxysilane ((C2H5O)3SiH). Polymers and oligomers terminated with hydrosilanes are resins that are used to make useful materials like caulks. Synthesis Trichlorosilane is produced commercially by the reaction of hydrogen chloride with silicon: :Si + 3 HCl → HSiCl3 + H2 Many alkoxy hydrosilanes are generated by alcoholysis of trichlorosilane. One example is triethoxysilane: :HSiCl3 + 3EtOH → HSi(OEt)3 + 3 HCl Organohydrosilanes can be prepared by partial hydrosilation of silane itself: :SiH4 + 3 C2H4 → HSi(C2H5)3 In the laboratory, hydrosilanes classically are prepared by treating chlorosilanes with hydride reagents, such as lithium aluminium hydride: :4ClSi(C2H5)3 + LiAlH4 → 4HSi(C2H5)3 + LiAlCl4 Structure The silicon-to-hydrogen bond is longer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dodecamethylcyclohexasilane
Dodecamethylcyclohexasilane is the organosilicon compound with the formula . It is one of the more readily prepared and easily handled polysilanes. Dodecamethylcyclohexasilane is produced by reduction of dimethyldichlorosilane with sodium-potassium alloy: : where M is Na or K. The reaction also produces polydimethylsilane and decamethylpentasilane. The chair conformer was confirmed by X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles .... Reactions Dodecamethylcyclohexasilane reacts with potassium ''tert''-butoxide to give the potassium derivative: :{{chem2, (CH3)12Si6 + KOC(CH3)3 → K(CH3)11Si6 + CH3OC(CH3)3 References Carbosilanes Silanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silenes
Silene, or disilalkenes,Philip P. Power "pi-Bonding and the Lone Pair Effect in Multiple Bonds between Heavier Main Group Elements" Chemical Reviews, 1999, 99, 3462. are silicon compounds that contain Si=Si double bonds. The parent silene is (the parent molecule) is disilene, . Structure The first transient disilene was reported in 1972 by D. N. Roark and Garry J. D. Peddle. Simple disilenes easily polymerize. To suppress this tendency, bulky substituents are used. Indeed the first isolable disilene, tetramesityldisilene, was described in 1981 by West, Fink, and Michl. It was prepared by UV-photolysis of the related cyclic trisilane: : 2 i(mesityl)2sub>3 → 3 (mesityl)2Si=Si(mesityl)2 Structure of tetramesityldisilene tetramesityldisilene is a yellow-orange solid. The Si=Si double bond lengths of disilenes vary between 2.14 and 2.29 Å and are nearly 5 to 10% shorter than the Si-Si single bond lengths of corresponding disilanes. A peculiarity of disilenes is the ''trans' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysilanes
Polysilanes are organosilicon compounds with the formula (R2Si)n. They are relatives of traditional organic polymers but their backbones are composed of silicon atoms. They exhibit distinctive optical and electrical properties. They are mainly used industrially as precursors to silicon carbide. The simplest polysilane would be (SiH2)n, which is mainly of theoretical, not practical interest. Synthesis left, Dodecamethylcyclohexasilane is a crystalline polysilane. The first polysilane, poly(dimethylsilylene), CH3)2Sisub>''x'', was reported in 1949 by Charles A. Burkhard (1916 - 1991) of General Electric. It was prepared by heating sodium metal with dimethyldichlorosilane: :(CH3)2SiCl2 + 2 Na → CH3)2Sisub>n + 2 NaCl The modified Wurtz coupling of dichlorosilanes remains a viable and general route to high molecular weight, linear polysilane derivatives. This reaction is conducted at elevated temperature in an inert solvent using a dispersion of the alkali metal. The polymerizat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetramethylsilane
Tetramethylsilane (abbreviated as TMS) is the organosilicon compound with the formula Si(CH3)4. It is the simplest tetraorganosilane. Like all silanes, the TMS framework is tetrahedral. TMS is a building block in organometallic chemistry but also finds use in diverse niche applications. Synthesis and reaction TMS is a by-product of the production of methyl chlorosilanes, SiCl''x''(CH3)4−''x'', via the direct process of reacting methyl chloride with silicon. The more useful products of this reaction are those for ''x'' = 1 (trimethylsilyl chloride), 2 ( dimethyldichlorosilane), and 3 (methyltrichlorosilane). TMS undergoes deprotonation upon treatment with butyllithium to give (H3C)3SiCH2Li. The latter, trimethylsilylmethyl lithium, is a relatively common alkylating agent. In chemical vapor deposition, TMS is the precursor to silicon dioxide or silicon carbide, depending on the deposition conditions. Uses in NMR spectroscopy Tetramethylsilane is the accepted int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexamethyldisiloxane
Hexamethyldisiloxane (HMDSO) is an organosilicon compound with the formula O i(CH3)3sub>2. This volatile colourless liquid is used as a solvent and as a reagent in organic synthesis. It is prepared by the hydrolysis of trimethylsilyl chloride. The molecule is the protypical disiloxane and resembles a subunit of polydimethylsiloxane. Synthesis and reactions Hexamethyldisiloxane can be produced by addition of trimethylsilyl chloride to purified water: : 2 Me3SiCl + H2O → 2 HCl + O i(CH3)3sub>2 It also results from the hydrolysis of silylethers and other silyl-protected functional groups. HMDSO can be converted back to the chloride by reaction with Me2SiCl2.Röshe, L.; John, P.; Reitmeier, R. “Organic Silicon Compounds” ''Ullmann’s Encyclopedia of Industrial Chemistry''. John Wiley and Sons: San Francisco, 2003. . Hexamethyldisiloxane is mainly used as source of the trimethylsilyl functional group (-Si(CH3)3) in organic synthesis. For example, in the presence of acid c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organosilicon Compound
Organosilicon compounds are organometallic compounds containing carbon–silicon chemical bond, 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 chemistry, 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 Ethanol, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
