HIGHLY SELECTIVE MONO-ALLYLATION AND POLYALLYLATION OF POLYCHLOROSILANES AND POLYCHLORODISILANES

The reaction of methyltrichlorosilane with an equimolar amount of ally l chloride in the presence of zinc powder proceeds quite smoothly in d imethylimidazolidinone (DMI) to give allyl(dichloro)methylsilane in hi gh selectivity. Other RSiCl3 (R = isopropyl, tert-butyl, n-hexyl, phen yl, n-octyl, n-decyl) gave the corresponding allylated compounds, (CH2 =CHCH2)-RSiCl2, highly selectively in high yield under the same condit io ns. Dimethyl dichlorosilane and trimethylchlorosilane are also mono allylated. The reaction of 2 equiv of allyl chldride-Zn-DMI with methy ltrichlorosilane gave the diallylated compound selectively. The reacti on of methyltrichlorosilane with (E)-1-chloro-2-butene selectively aff orded 1-methyl-2-propenyl(methyl)dichlorosilane with allylic rearrange ment. The reaction was also applied, successfully to the allylation of polychlorodisilanes.