Bis trimethylsilylmethyl benzene

A solution of the di-Grignard reagent, prepared as described on p. 34 (but not filtered), is cooled by an ice bath and stirred rapidly as chlorotrimethylsilane (4.4 ml, 35 mmol) is added during 2 h. The mixture is stirred at room temperature for 2 h, and the solvent and excess 

Synthesis of organosilicon compounds from organomagnesium compounds 

In others, however, other pathways are probably involved, for example involving electron transfer mechanisms or silylmagnesium intermediates, and sometimes giving products different from, or unobtainable by, the two-step procedure. For example, reactions of aromatic carbonyl compounds with magnesium and chlorotrimethylsilane in hexametapol result in silylation at both carbonyl carbon and carbonyl oxygen  

Such reactions have been reviewed [23], and a procedure for the preparation of arylsilanes is given in a companion volume [24], 

Colvin, Silicon Reagents in Organic Synthesis, Academic Press, London, 1988. 

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