Synthesis of indole-fused benzodiazepine derivatives by photocatalyzed cascade reaction.

We report a cascade synthesis of indole-fused benzodiazepines by the photocatalyzed addition of phenacyl radical, generated from α-acetoxy acetophenone, to 2-(3-methyl-1H-indol-1-yl)aniline, and subsequent cyclodehydration. A range of indole-fused benzodiazepines were obtained from readily available substrates.