LAUSR

Diazoacetates are widely used to synthesize highly valuable indoles. Previous research has focused on using metal carbene reactivity or the innate nucleophilicity of the diazoacetates to create indoles through a traditional two-electron pathway. However, these strategies are constrained by the need for transition metals, oxidants, or substrate prefunctionalization. To overcome the limitations, we report herein an open-shell strategy that utilizes the radical reactivity of diazoacetates to synthesize indoles for the first time, especially for more valuable [a]-annulated indoles. Notably, this visible-light-driven transformation is enabled by a single organophotocatalyst, proceeding without metals ot additives. Preliminary mechanistic studies and density functional theory calculations disclose a relay visible-light photoredox catalytic process that probably involves several discrete photoredox catalytic cycles in a single operation with one organophotocatalyst.