Synthesis of Indoloazepinone Scaffolds Using Sequential Photochemical and Photocatalytic Reactions.

Indoloazepinone scaffolds show promise as anticancer compounds; however, current methods for their synthesis rely on azepinone ring formation from prefunctionalized indoles. Herein, we report an alternative strategy for the rapid synthesis of indoloazepinones from dichloromaleimides and anilines using sequential photoinduced reactions, including a photochemical [5 + 2] cycloaddition and a photoredox-catalyzed dechlorinative indole formation. Construction of the indole core late in the synthesis allowed straightforward diversification of the benzenoid ring with a variety of functional groups.