Modular Synthesis of 1,2-Benzothiazines and 1,2-Benzothiazine 1‑Imines via Palladium-Catalyzed C–H/C–C Activation Reactions

In this study, a modular approach toward cyclic sulfoximines and sulfondiimines via palladium-catalyzed intramolecular C–H/C-C activation reactions was reported. Various 1,2-benzothiazines including bicyclic, tricyclic, highly fused ones, ones of the seven-membered ring, along with 1,2-benzothiazine 1-imines were accessed in good yields. KIE experiment demonstrated that the C–H bond cleavage at the position ortho to the sulfoximine group is not the rate-determining step in the coupling reaction