Silicon atoms reaction

The majority of the information on silicon atom reactions is derived from studies involving the formation of Si yia nuclear transformation.Silicon-31 atoms have been generated by the following two nuclear processes (i) and (ii) Si( ,y) Si. Of the two, the first one is the most fre-... 

On the other hand, Skell and Owen have indicated that Si-Si bond insertion is unlikely for thermally evaporated silicon atoms. The contradictory conclusion invoked by Cetini and coworkers as described above should be taken with caution. The (n,y) nuclear process employed involves a number of potential complications, which will be discussed in detail in Section III.7. Overall it seems that Si-Si insertion, although a possible reaction mode, is not yet well established for silicon atom reactions. 

A silicon atom might be expected to release electrons inductively, but because of empty 7-orbitals shows the overall character ( + 7 —717). Nitration of trimethylsilylbenzene with nitric acid in acetic anhydride at —10 to o °C gives 25-5,39-8,30-2 and 6-8 %, respectively, of 0-, m-, and /)-nitro-trimethylsilylbenzene and nitrobenzene, with a rate of reaction relative to that of benzene of about 1-5. The figures give no indication of an important conjugative effect. 

Neutrons also transform some of the silicon atoms to phosphoms through the following reaction ... 

The ether-forming step is an S -like reaction of the alkoxide ion on the silicon atom, with concurrent loss of the leaving chloride anion. Unlike most Sn2 reactions, though, this reaction takes place at a tertiary center—a trialJkyl-substituted silicon atom. The reaction occurs because silicon, a third-row atom, is larger than carbon and forms longer bonds. The three methyl substituents attached to silicon thus offer less steric hindrance to reaction than they do in the analogous ferf-butyl chloride. 

The surface of glass contains many —OH groups that are bonded to the silicon atoms of Si02, which is the major component of glass. If the glass is treated with Si(CH3)3Cl (chlorotrimethylsilane), a reaction takes place to eliminate HC1 and attach the Si atom to the oxygen atom ... 

The reduction of tributyltin methoxide with optically active methyl-phenyl-1-naphthylsilane involves retention of configuration at the silicon atom and follows second-order kinetics (2 72). The reaction between tributyltin methoxide and ring-substituted dimethylphenylsilanes shows a Hammett p-value of -t-0.903, and that between dimethyl-phenylsilane and ring-substituted tributyltin phenoxides shows a p-value of -1.319 this is compatible with the reactions proceeding through a 4-centered (SNi-Si) transition state (272, 173). 

Dihydro-lH-l,5,2-azasilaboroles derive from the 2,5-dihydro-lH-l,2-aza-boroles ( 6.5.3.3) by substitution of the carbon neighboring N by a silicon atom. They may act as four-electron donors using electron density from the C=C double bond and the N atom. The B atom behaves as an acceptor center. Two pathways are known for complex synthesis reaction with a generated transition-metal complex fragment and reaction with metal atoms by the metal-vapor synthesis method. 

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