Eosin Y catalyzed difunctionalization of styrenes using O2 and CS2: a direct access to 1,3-oxathiolane-2-thiones

Visible light promoted straightforward highly regioselective synthesis of 1,3-oxathiolane-2-thiones (cyclic dithiocarbonates) starting directly from styrenes, CS2 and air (O-2) is reported. The protocol utilizes eosin Y as an organophotoredox catalyst and clean resources like visible light and air (02) as sustainable reagents at room temperature in a one-pot procedure. Additionally, the approach is advantageous in terms of step economy as it skips the prefunctionalization of styrenes to oxiranes, which has been inevitable in commonly used syntheses of 1,3-oxathiolane-2-thiones.