Visible-Light Photoredox-Catalyzed Giese Reaction of α-Silyl Ethers with Various Michael Acceptors.

We developed a photocatalyzed Giese reaction of various weakly activated Michael acceptors with a neutral silicon-based radical precursor and applied it at large-scale using a continuous flow reactor. The developed method successfully overcomes the substrate scope limitations of previous studies, shows good functional groups tolerance, and affords good to excellent yields. On the basis of mechanistic studies, we propose a reaction mechanism that involves an generated alkoxymethyl radical via single-electron oxidation of α-trimethylsilyl-substituted ethers.