Visible-Light-Driven Germyl Radical Generation via EDA-Catalyzed ET-HAT Process.

We have established a facile and efficient protocol for the generation of germyl radicals by employing photo-excited electron transfer (ET) in an electron donor-acceptor (EDA) complex to drive hydrogen-atom transfer (HAT) from germyl hydride (R3GeH). Using a catalytic amount of EDA complex of commercially available thiol and benzophenone derivatives, the ET-HAT cycle smoothly proceeds simply upon blue-light irradiation without any transition metal or photocatalyst. This protocol also affords silyl radical from silyl hydride.