Group silicon halides

The position of iodosilane and iodotrimethylsilane in the heavy salt conversion series1,2 is such that iodosilane and its methylated analogues may be used as sources for the [(CH3) SiH3. ] - (n = 0-3) groups in the preparation of a wide variety of silicon halides 3 pseudohalides, 6 chalcogenides,s,7,s and group V derivatives.9... 

R)C2B4H5] ions and appropriate main group element halides, have structures containing central main group elements in the 4+ oxidation states similar to the bis-dicarbollide silicon sandwich compound. The structure of the silicon sandwich compound 0 0-[ (CH3)3Si 2C2B4H4]2Si is shown in Figure 27. 

At present, primarily the binary compounds have been studied, and considerations of product volatility are the most significant driving force behind much of this research. The group III—V compounds are particularly difficult, because the group V elements form volatile halides, whereas group III halides, particularly the fluorides, tend to be involatile. As a result, F source plasmas, which have been the mainstay of silicon technology, are... 

The reactions of silicon halides with organomagnesium or organolithium compounds for the synthesis of organosilicon compounds are oversimplified in Eqs. (3) and (4). If several reactive groups are attached to the silicon atom, as in C2H5SiCl3, the reaction cannot be controlled so as to yield a particular substitution product, since all possible substitutions will occur simultaneously. All that can be done is to favor the yield of the desired compound by manipulation of reaction conditions. 

Another characteristic reaction of the silicon halides is the reaction with ethylene oxide to form a 0-chloroethyl or 0-bromoethyl group 25... 

At first it was thought that the copper methyl might react with the silicon halide in the manner of a Grignard reagent, but copper ethyl and copper phenyl prepared in ether suspension did not react with silicon tetrachloride. Neither did free methyl radicals from lead tetramethyl react with elementary, silicon, but they did add on silicon that was being chlorinated. This suggests that the third step in the mechanism is the addition of methyl groups to the chlorinated silicon formed in the cuprous chloride reduction ... 

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