Double silylation of olefin with HSiCl3 in the presence of Bu4PCl.: New synthetic method for α,β-bis(trichlorosilyl)alkanes

Terminal and activated internal olefins such as 1-hexene, 1-decene, styrene, p-methylstyrene, 1-phenylprop-lene, and stilbene reacted with a mixture of HSiCl3 and SiCl4 in the presence of Bu4PCl at 180 degrees C for 4-16 It to give the alpha,beta- bis(trichlorosilyl)alkanes 2 (70-85%) and alkyltrichlorosilanes 3 (10-21%). However, the reactions of the unactivated internal olefins 3-hexene and cyclopentene for 32 It under the same conditions gave 41% and 85% consumption and produced the bis-silylation compounds 2 in 12 and 43% yields along with hydrosilylation products 3 in 24 and 28% yields, respectively.