Synthesis of Biaryl Sultams Using Visible‐Light‐Promoted Denitrogenative Cyclization of 1,2,3,4‐Benzothiatriazine‐1,1‐dioxides.

A novel approach has been reported for the preparation of biaryl sultams using visible-light-promoted denitrogenative cyclization of 1,2,3,4-benzothiatriazine-1,1-dioxides. A variety of biaryl sultams have been prepared with the assistance of a photocatalyst under visible light at room temperature with satisfactory yields. Both stepwise and one-pot procedures have been developed, thus improving the practicability of this synthetic strategy.