Visible-Light-Mediated Synthesis of Phenanthrenes through Successive Photosensitization and Photoredox by a Single Organocatalyst

An efficient approach for the synthesis of phenanthrene scaffolds by utilizing the dual catalytic activity of an organo-photocatalyst is documented. The controlled cascade transformation proceeds via in situ diazotization followed by olefin isomerization and subsequent arene radical generation through photoreduction. The overall process demonstrates both the photosensitization and photoredox properties of a single organo-photocatalyst and facilitates the desired intramolecular annulation with high precision and efficacy. In this context, the underexplored organocatalyst acridine orange base is employed and the photophysical interactions between the catalyst and the substrates along with the detailed reaction kinetics are documented.

Automated summary

An efficient approach utilizing the dual catalytic activity of an organo-photocatalyst for the synthesis of phenanthrene scaffolds is documented. The controlled cascade transformation involves in situ diazotization, olefin isomerization, and photoreduction for the generation of arene radicals. The study explores the underexplored organocatalyst acridine orange base and investigates the photophysical interactions and reaction kinetics.