Silicon chlorine

Much of the known high-temperature chemistry of silicon-chlorine compounds is indirectly concerned with SiCl2. The reactions discussed below will serve as examples of those in which the intermediacy of SiCl2 is indicated. 

Mass spectrometric investigations of the silicon-chlorine system do not seem to have been made. 

Brown and coworkers (17-18,47) reported compositions of dusts from cotton compresses and warehouses. Samples were removed with the aid of a sonic bath in hexane. The compresses were in Mississippi, Southeastern and Western Texas, and New Mexico. The samples in the bale press area were high in ash content with silicon the most abundant element (up to 18.7% in one New Mexico compress Scimple). Compared with card room dusts, samples from compresses were high in aluminum, silicon, chlorine, iron and magnesium and relatively low in potassium, phosphorus and zinc. The ratio of silica to silicon was high also for these scunples compared with textile mill dusts. 

It was found that silicon-bromine and silicon-chlorine bonds were thermodynamically activated towards substitution by coordination of an oxygen nucleophile, whereas coordination was found to deactivate the silicon-fluorine bond. 

Cholorosllones, SiHxCl, compds of silicon, chlorine and hydrogen where the total number of atoms of chlorine hydrogen or hydrogen subs tituted radicals adds up to 4... 

Chlorosilane. A chlorine derivative of a silane a compound containing at least one silicon-chlorine bond. 

Monochlorosilane. The compound HsSiCl in general, a compound of silicon containing only one silicon-chlorine bond. 

Moreover, the kinetic curves (obtained from GC analysis) of the electrochemical reduction of PhMeSiCl2 with an A1 anode, as an example, show that the two silicon-chlorine bonds are reduced in two well-separated steps (Fig. 2) ... 

The arsenic acids have no structural parallel in the heavier elements of Group IV (Si, Ge, Sn, Pb) but appear to function as a carboxylic acid would in ring-closure reactions. The contrast in behavior of an As—Cl bond toward electrophilic attack on a benzene ring versus Si—Cl reactivity should be noted. No clear-cut examples of a Friedel-Crafts reaction involving a silicon-chlorine bond have been reported 107). 

The silanorbomenes 1, 2, and 3 can be synthesized according to the literature [1, 2]. Hydrogen chloride cleavage of 3 leads to the silicon chlorinated precursor of 13, which is obtained by a Grignard reaction with naphthyl magnesium bromide in high yield (86 %). Similarly, 15 is available from HCl cleavage of 1 and reaction of the latter with fluorenyl lithium. The silicon-chlorinated silacyclobutanes 7, 8, and 11 are synthesized by [2+2]-cycloaddition of dichloroneopentylsilene with isoprene and dimethylbutadiene, respectively [3],... 

We would like to suggest, that an attack of a chlorine takes place first at one of the silicon atoms of the tri- or tetrasilane under discussion to form a pentacoordinated silicon. In a second step, a silylene is generated which inserts into a silicon-chlorine bond of the disilane while the silicon skeleton of the oligosilane is shortened by one silicon atom. The source of the attacking chlorine is not yet known An intramolecular reaction with a chlorine of a chloromethylsilyl-sidechain and the central silicon might occur, or remaining traces of the aluminium trichloride, used for the chlorination, might induce the reaction. This is possible since only catalytic amounts would be necessary to cause the decomposition. 

Hexachlorodisiloxane is a colorless liquid boiling at 137°. It is the first member of the open-chain series of oxy-halides of general composition Si 0 -iCl2n+2. The reactivity of the silicon-chlorine bond in the molecule is... 

Baney and Gaul synthesized methylchloropolysilane from disilanes ( i-Si=) by redistribution reactions of silicon-chlorine/silicon-silicon bonds [9,10]. Distilled mixed disilanes were catalytically rearranged with tetrabutylphosphonium chloride (1%) to produce preceramic polymer. The polymer obtained is considered to have a polycyclic -Si-Si- chain. The structural units are sSi (CH3), =Si(CH3)2, and =Si(CH3)Cl. Several new polymers were derived from methylchloropolysilane by substituting the remaining silicon-chlorine bonds by other chemical groups [11]. 

Polydisilylazanes have been synthesized by the reaction of mixed disilanes with hexamethyldisilazane through silicon-chlorine/silicon-nitrogen bond redistribution reactions [10,26]. The formula [(CH3)2.6(Si2)i.oNHi.5]n was deduced during (reaction) at 250°C. 

A polymeric compound contains several different molecules e.g., carbon, hydrogen, oxygen, silicon, chlorine, sulphur. These molecules combine in small groups usually with a carbon molecule in the middle. The group is repeated linearly many times in the form of a chain. 

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