Synthesis of Functionalized 4,1‐Benzothiazepines via a [4+3] Annulation between Aza‐o‐Quinone Methides and Pyridinium 1,4‐Zwitterionic Thiolates

Abstract The [4+3] annulation of aza‐ o ‐quinone methides and pyridinium 1,4‐zwitterionic thiolates has been developed for the one‐step synthesis of functionalized 2,3‐unsaturated 4,1‐benzothiazepines under mild and metal‐free conditions. The produced 4,1‐benzothiazepines can easily be converted into biologically interesting sulfoxides and sulfones via selective oxidization with m ‐CPBA. magnified image