Visible-Light-Promoted Iron-Catalyzed Amidation/Cyclization of Arylacrylamides with Dioxazolones

A visible-light-promoted and simple iron salt-catalyzed cascade amidation/cyclization of <i>N</i>-aryl acrylamides with dioxazolones was developed. The reaction proceeds under photosensitizer-free conditions and features satisfactory to good yields, broad functional group tolerance, and an easy operation procedure. Mechanistic studies revealed that the reaction proceeded via an iron-nitrene intermediate. This method may contribute to shift the paradigm of iron-catalyzed C-N bond construction and nitrene transfer chemistry.