Visible-Light-Driven C–H Arylation of Aminoquinones with Diaryliodonium Salts

A visible-light-driven C-H arylation of 2-amino-1,4-naphthoquinones with diaryliodonium salts has been developed using 10-phenylphenothiazine (PTH) as a photocatalyst. Mechanistic studies reveal that aminoquinone serves both as the substrate and as an electron shuttle in the electron transfer from PTH to the diaryliodonium salts. The combination of this photo-driven C-H arylation with an intramolecular SNAr cyclization provides a streamlined route to carbazolequinone scaffolds, significantly facilitating the synthesis of medicinally relevant tetracyclic architectures.