Three-Component Radical C-H Selenylation of N-Acyl Anilines under Metal-Free Conditions.

We have developed a metal-free platform that enables the efficient synthesis of functional 4-arylselenylated anilines via bromide-catalyzed three-component site-selective radical C-H selenylation of N-acyl anilines using elemental Se and boronic acids as the selenyl precursors. This strategy utilizes commercially available and industrially applicable Se powder as the building block for selenium-containing motifs, circumventing the need for selenyl precursors that are toxic, unstable, and difficult to store. A wide range of arylboronic acids, including sterically congested boronic acids, are smoothly accommodated with this method. The potential synthetic utility is highlighted by its operational simplicity, extensive substrate scope, good functional group compatibility, gram-scale synthesis, and transformations. Furthermore, preliminary mechanistic experiments revealed that a radical pathway is integrated in this transformation.