Hydride abstraction initiated hydrosilylation of terminal alkenes and alkynes on porous silicon

Hydride abstraction by triphenylcarbenium cations in the presence of terminal alkynes and alkenes results in hydrosilylation at room temperature on hydride-terminated porous silicon surfaces, leading to alkenyl- and alkyl-terminated surfaces, respectively. A wide range of surface terminations are possible as the reaction conditions tolerate a variety of functional groups. Silicon-carbon bond formation is substantiated by Fourier transform infrared and C-13 solid-state NMR spectroscopies, in addition to chemical and stability studies. Generation of an energetic surface silicon-based positive charge is thus a viable route to the formation of silicon-carbon bonds via hydrosilylation, a step previously postulated for the mechanism of exciton-mediated hydrosilylation on photoluminescent nanocrystalline silicon.