Photocatalytic C-Si Bond Formations Using Pentacoordinate Silylsilicates as Silyl Radical Precursors: Synthetic Tricks Using Old Reagents.

A visible-light-induced photocatalytic C-Si formation strategy has been disclosed by uncovering the reactivity of Martin's spirosilane-derived pentacoordinate silylsilicates as silyl radical precursors. The hydrosilylation of a broad spectrum of alkenes and alkynes, as well as the C-H silylation of heteroarenes, has been demonstrated. Remarkably, Martin's spirosilane was stable and could be recovered via a simple workup process. Furthermore, the reaction proceeded well using water as the solvent or low-energy green LEDs as an alternative energy source.

Synthesis of ß-Silyl α-Amino Acids via Visible-Light-Mediated Hydrosilylation.

An expedient synthesis of ß-silyl α-amino acids is reported via the application of visible-light-mediated hydrosilylation. The reaction utilizes readily accessible and structurally diverse hydrosilanes to provide radicals for conjugate addition to dehydroalanine ester and analogues. Notably, the use of chiral methyleneoxazolidinone as the substrate and chiral inducer enabled the highly stereoselective synthesis. Furthermore, the reaction could also be performed in a continuous flow fashion and scaled up to the gram scale.