The activity and selectivity influenced by Rh(PPh₃)₃Cl/dialkylimidazolium hexafluorophosphate or N-alkylpyridinium hexafluorophosphate have been investigated in the hydrosilylation of olefin with triethylsilane. It was found that both conversion and selectivity to β-product could be improved, but the selectivities to α-product and unsaturated product decreased by using this catalyst. The Rh(PPh₃)₃Cl/C₁₆PyPF₆ exhibited the highest selectivity to β-product in the hydrosilylation of styrene by triethylsilane. The conversion of styrene was 95.7%, the selectivity to β-product was 87.8%, the selectivity to α-product was 0.001%, and the selectivity to unsaturated product was 9.2%. At the same time, this catalyst might be reused more than seven times without noticeable loss of its catalytic activity.

Key words: Rh(PPh₃)₃Cl, dialkylimidazolium hexafluorophosphate, N-alkylpyridinium hexafluorophosphate, hydrosilylation, triethylsilane