Silicon tetrachloride hydrocarbons

Silicon tetrachloride undergoes addition with olefinic and acetylenic unsaturated hydrocarbons. In these addition reactions, one chlorine atom adds to one carbon atom of the double or triple bond while the rest of the unit —SiCls attaches to the other carbon atom forming a sihcon—carbon bond ... 

This process is also possible in a hydrocarbon medium with tetraethox-ysilane or diethyl ether (1%) as a catalyst, both in two and one stages, by the interaction of the mixture of silicon tetrachloride and alkyl- or aiylha-logenide with metallic magnesium in a solvent medium (toluene or xylene). 

Absorption op Hydrocarbons. One of the newest substitution methods does not involve conversion of free metal to metallic halide as a part of the process. Instead, unsaturated hydrocarbons or carbon monoxide are absorbed directly by silicon tetrachloride at pressures of 10 to 100 atm. and in the presence of metallic chlorides or oxychlorides as catalysts.13 If ethylene is absorbed, the product is -chloroethyltrichlorosilane ... 

A somewhat similar process makes use of the gas-phase reaction of aliphatic hydrocarbons with a silicon halide14 at a high temperature. Thus a mixture of silicon tetrachloride and an aliphatic hydrocarbon may be heated to a temperature above 450° (but below the temperature of thermal decomposition of the hydrocarbon) to produce organosilicon halides. 

Another method about which too little is known for a fair evaluation in this chapter makes use of the reaction of aliphatic hydrocarbons with silicon chlorides at high temperatures.1 Silicon tetrachloride, for example, is mixed in the vapor phase with an aliphatic hydrocarbon corresponding to the alkyl group to be attached to the silicon, and the mixture is heated to a temperature of 450° or more. The products then are cooled and condensed, and the organosilicon compounds are separated by distillation. Stated in its general form, the reaction offers decided promise as a means of using hydrocarbons directly in organosilicon syntheses. 

Shtetter synthesis. The process of forming chloroalkyl compounds of silicon by absorbing unsaturated hydrocarbons in silicon tetrachloride under pressure and with the aid of metallic chlorides or oxychlorides as catalysts. The method was patented by I. I. Shtetter in 1935. 

Liquids agreeing with (3) are called normal liquids they include benzene and other hydrocarbons (aliphatic and aromatic), ether, carbon tetrachloride, carbon disulphide, ethyl iodide, nickel carbonyl, sulphuryl chloride, sulphur chloride, phosphorus trichloride, phosphorus oxychloride, silicon tetrachloride, and nitrogen dioxide. 

However, the most far-reaching and almost universally applicable method for synthesis of organosilicon compounds is by the action of Grignard reagents on silicon halides. With silicon tetrachloride this gives a mixture of products in which one to four chlorine atoms have been replaced by hydrocarbon groups ... 

The most widely used method of analysis for methylene chloride is gas chromatography. A capillary column medium that does a very good job in separating most chlorinated hydrocarbons is methyl silicone or methyl (5% phenyl) silicone. The detector of choice is a flame ionization detector. Typical molar response factors for the chlorinated methanes ate methyl chloride, 2.05 methylene chloride, 2.2 chloroform, 2.8 and carbon tetrachloride, 3.1, where methane is defined as having a molar response factor of 2.00. Most two-carbon chlorinated hydrocarbons have a molar response factor of about 1.0 on the same basis. 

This includes bioremediation cases of contaminated sites with several toxic and carcinogenic pollutants, such as petroleum hydrocarbons, PAHs, dichlorobenzene, chlorinated hydrocarbons, carbon tetrachloride, Dicamba, methyl bromide, trinitrotoluene, silicon-based organic compounds, dioxins, alkyl-phenol polyethoxylates, nonylphenol ethoxylates, and polychlorinated biphenyls. The following is a brief summary of each case. 

BUNA N (nitrile) Aromatic hydrocarbons, dilute acids and bases, silicones, helium hydrogen Halogen compounds, halogenated hydrocarbons (carbon tetrachloride, trichlorethylene), ketones (acetone), nitro compounds, or strong acids Typical color black. Temperature range -50 to 120°C. Easily compressed. Density 1.00. Lowest permeability rates for gases of all elastomers. 0.25... 

The HNMR spectra of the silicon ethers appear quite similar to those of the aliphatic ethers. The presence of the silicon nucleus can normally be detected only when a hydrocarbon group is bonded directly to it. The silicon ethers are readily soluble in carbon tetrachloride and deuterochloroform. 

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