Visible-Light-Mediated Metal-Free Synthesis of Aryl Phosphonates: Synthetic and Mechanistic Investigations

This work describes a straightforward access to a large variety of aryl phosphonates by the simple combination of diaryliodonium salts with phosphites in the presence of a base and under visible-light illumination. The reaction proceeds smoothly, tolerates various functionalities, and was applied for the synthesis of pharmaceutically relevant compounds. Mechanistic investigations, including EPR, NMR, and DFT calculations, support the postulated reaction mechanism.