Varying Si-Chlorinated 2-Methyl-2-chloro-l,3-disilapropanes

ClMe2Si-CMeCl-SiMe2Cl 247 + MeMgCl (excess) 247 + MeMgCl (excess)  

Cl2MeSi-CMeCl-SiCl3 248 MeMgCl =1 2 Prod. mixt. (reaction 1 2)  

From the isolated products, one cannot determine which level of substitution on silicon is decisive for a transmetallation reaction to take place. However, if the formation of the methylidene group is completed by elimination of HMgCl, subsequent methylation of the remaining SiCl group will be so rapid that formation of SiH groups will not occur. Through the influence of the C = C double bond on the Si atoms, an increased reactivity of the Si—Cl bond becomes apparent. 

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