Benzene Silicon tetrachloride

FIGURE 3 2 Solvent extraction efficiencies (EF) as functions of dielectric constants (D), solubility parameters (6), and polarity parameters (P and E -). Solvents studied silicon tetrachloride, carbon disulfide, n pentane. Freon 113, cyclopentane, n-hexane, carbon tetradiloride, diethylether, cyclohexane, isooctane, benzene (reference, EF 100), toluene, trichloroethylene, diethylamine, chloroform, triethylamine, methylene, chloride, tetra-hydrofuran, l,4 dioxane, pyridine, 2 propanol, acetone, ethanol, methanol, dimethyl sulfoxide, and water. Reprinted with permission from Grosjean. ... 

According to E. Lay, if a soln. of silicon tetrachloride in benzene be mixed with an emulsion of hydrazine in dry benzene, a white powder is obtained which is a mixture of crystals of hydrazine diehloride, and amorphous grains of a substance with the empirical composition, Si(NH)4, or Si(N2H2)2. A separation with organic solvents is not possible. 

Silicon tetrachloride (20 gms.) is mixed willi clilorhonzono (50 gms.) and four times l.lio volume of dry ether, and a small quantity of acetic ester (I to 2 gms.) added. Tlio Hash is attached to a rollnx condenser, ami then sodium (25 gms.) in small pieces is gradually added. A vigorous reaction follows and the flask should be repeatedly shaken. When the roaoLion is completed, water is added hi remove any nnn.ttii.ekod sodium, and then enough to dissolve the sodium chloride, after which the mixture is extracted with hot. benzene. White crystals separate from the benzene solution, m.p. 22H°. 

Stable at room temperature but decomposes at approximately 400°C. Slowly decomposes in water practically insoluble in alcohol, ether, benzene, chloroform, silicochloroform, and silicon tetrachloride. Decomposes in potassium hydroxide solutions.1... 

Thus, the direct synthesis of phenylchlorosilanes produces a complex mixture, which, apart from phenyltrichlorosilane, diphenyldichlorosilane, phenyldichlorosilane and triphenylchlorosilane, also contains silicon tetrachloride, trichlorosilane, benzene, solid products (diphenyl and carbon) and a gaseous product (hydrogen). It also forms high-boiling polyolefines, which are part of tank residue and can deposit on contact mass, reducing its activity. It should be kept in mind that the production of phenylchlorosilanes requires silicon with a minimal impurity of aluminum, because the aluminum chloride formed contributes to the detachment of the phenyl group from phenylchlorosilanes at higher temperature. The harmful effect of aluminum chloride is counteracted by the addition of metal salts to contact mass, which form a nonvolatile and nonreactive complex with aluminum chloride. 

C (intermediate), containing a mixture of silicon tetrachloride and benzene. It can be used in phenylchlorosilane synthesis by high-temperature condensation to suppress the secondary process of reduction. 

In this case, similarly to the vinyltrichlorosilane case, in the conditions of synthesis (600-640 °C) there is a secondary reaction of reduction, which forms silicon tetrachloride and benzene. However, if the process is conducted in the presence of an initiator (5% of diazomethane), it is possible to reduce the temperature down to 500-550 °C. Then the secondary reaction proceeds very slowly, which increases the yield of phenyltrichlorosilane by 1.5 times. To suppress the reduction process, one can also add... 

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. 

Chloroacetophenone is soluble in alcohol, benzene (40% by weight), ether and carbon disulphide, as well as in many of the other war gases. For instance, phosgene dissolves 9 5% by weight, and cyanogen chloride 63% by weight. It is, however, very slightly soluble in titanium tetrachloride, silicon tetrachloride or water (i gm. in 1,000 ml.). 

The pure compound crjrstallises in needles, M.pt. 288 C., which are soluble in benzene, xylene, or chloroform, less soluble in alcohol, and insoluble in water. Mercury di-p-tolyl gives the same type of products as mercury diphenyl (see table, p. 74) when it reacts with halogens, halogen acids, mercuric chloride, boron or arsenic trichlorides, phosphorus trichloride, silicon tetrachloride, nitrogen tri- and tetr-oxides, sulphur, selenium, and tellurium. ... 

Dry chlorine gas, hypochlorous acid, thallic chloride, silicon tetrachloride, stannic chloride, zirconium tetrachloride, phosphorus trichloride, mercurous chloride, thionyl chloride, benzene sulphonic chloride, benzal chloride,phenyl iododichloride. ... 

Derivation By Grignard reaction of silicon tetrachloride and phenylmagnesium chloride, reaction of benzene with trichlorosilane. 

To titrate alkylchlorosilanes such as trimethylsilicon chloride, dimethylsilicon dichloride, methylsilicon trichloride and silicon tetrachloride, titration in methyl cyanide with 0.05 n phenazone or nitron in methyl cyanide, or with a solution of amidopyrine in benzene by visual and potentiometric methods is suggested173. The indicators used are crystal violet, dimethylaminoazobenzene, bromocresol purple, methyl orange, bromo-phenol blue and gallo sea blue (C.I.-Mordant Blue 14) the addition of benzene, toluene, chlorobenzene or carbon tetrachloride does not effect the results. 

Down to 0.0001%, benzene in silicon tetrachloride could be determined in a column containing petroleum jelly on firebrick with flame ionisation detector and hydrogen as the carrier gas. The minimum determinable amount of benzene is 10 5 mg, with a relative error of 7.2%. The method was also applied to the determination of benzene in trichlorosilane. 

Gas, repulsive odor. d, s (liq) 0.68. Solidifies at approx —200. mp —185 bp —112. Stable at ordinary temps completely dec at approx 400° into silicon and hydrogen dec by an electric discharge ignites in an atm of chlorine ignites in air by raising the temp. Slowly dec in water practically insol in ale, ether, benzene, chloroform, silicochloroform and silicon tetrachloride. Dec in potassium hydroxide solns. 

Even though the preparation of tetraisocyanatosilane has been previously described in Inorganic Syntheses, there exists a less time-consuming and far less expensive patented procedure that has been largely overlooked. This procedure involves the reaction of silicon tetrachloride with sodium or potassium cyanate in place of the silver or lead salt, which first must be freshly prepared. The use of liquid sulfur dioxide as the solvent, instead of benzene, offers no real increase in handling problems. The details of this alternate method adapted to a laboratory... 

DisiUcon hexabromide, hexabromodisUane, forms well-crystallized white plates or prisms (m.p. 95°, b.p. 265°). It is soluble in a variety of organic solvents, such as carbon tetrachloride, chloroform, carbon disulfide, and benzene, as well as in silicon tetrachloride or tetrabi omide. It is rapidly hydrolyzed by the moisture of the air, forming insoluble "silicooxalic acid, (H2Si204)x and with solutions of ammonia or of strong bases it forms sihcic acid or silicates, with liberation of hydrogen. 

Only a few binary miscible liquid systems obey Raoult s law throughout the complete range of concentrations. Examples of this type are carbon tetrachloride-silicon tetrachloride, ethylene dibromide-ethylene dichloride, benzene-ethylene dichloride, chlorobenzene-bromobenzene, hexane-heptane etc. Most systems, however deviate from Raoult s law to a greater or lesser degree depending on the nature of the liquids and the tenqterature. These are called real or non-ideal solutions. Completely miscible binary solutions can be divided into three categories. 

Determine the molecular and empirical formulas of the following (a) The organic solvent benzene, which has six carbon atoms and six hydrogen atoms, (b) The compound silicon tetrachloride, which has a silicon atom and four chlorine atoms and is used in the manufacture of computer chips. 

Attempts by Sucker and Amick (46) to reproduce Austin s work produced films which were unstable in air. Heat treatment at about 350°C was recommended to remove hydrogen from the films before they were exposed to air. Their recommended solvents were tetrahydrofuran/ benzene, tetrahydrofuran/toluene, dioxolane/benzene and dioxolane/ toluene, with silicon tetrachloride or trichlorosilane as solutes. The films contained both chlorine and chromium in trace amounts. 

Star polymers may be considered to be highly branched polymers that have linear chains radiating out from a central area. This area may be one atom, a small molecule, or a "core". The "core" is a quasi-spherical structure as opposed to a linear structure that would be present in a conventional comb or branched polymer. An early example of stars made from small molecules is the star polymer of Schaefgren and Flory (1) who polymerized E-caprolactam in the presence of a tetrafunctional or octafunctional carboxylic acid to produce polymers that have 4 or 8 arms radiating out from a central molecule. Other examples use the coupling of "living" anionically polymerized polystyrene with silicone tetrachloride (2) or chloromethyl-benzene (3). Recent work in this area includes that of Fetters (4) who has made 12 and 18 arm stars with this general technique. 

If this remains a laboratory process for aluminum or boron nitride, for silicon nitride it has reached the stage of industrial production. Silicon tetrachloride dissolved beforehand in a cyclohexane-benzene mixture reacts at -40°C with liquid ammonia to form solid polymeric silicidimide ... 

The precursor chains become the star branches, and the deactivator becomes the core (Scheme 1). The difficulty is identifying compounds carrying a number of equally reactive and equally accessible electrophilic functions needed to control the average number of branches of the stars. The induced deactivation must be fast, quantitative, and free of any side reactions. The limitations encountered include the low functionality of the substances used as deactivators such as chloromethylated benzenes [21,22], trisallyloxytriazines [23], and silicon tetrachloride [24] (Figure 2). 

Without carbon, the basis for life would be impossible. While it has been thought that silicon might take the place of carbon in forming a host of similar compounds, it is now not possible to form stable compounds with very long chains of silicon atoms. The atmosphere of Mars contains 96.2% CO2. Some of the most important compounds of carbon are carbon dioxide (CO2), carbon monoxide (CO), carbon disulfide (CS2), chloroform (CHCb), carbon tetrachloride (CCk), methane (CHr), ethylene (C2H4), acetylene (C2H2), benzene (CeHe), acetic acid (CHsCOOH), and their derivatives. 

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