Photocatalyzed E → Z contra-thermodynamic isomerization of enamides

The photocatalytic isomerization of enamides is an important strategy for accessing valuable (Z)-enamides with high selectivity. Herein, we reported an efficient photocatalytic activation of (E)-enamides via an energy transfer mechanism mediated by the excited state of Ir(ppy)₃. This protocol enables the highly selective synthesis of (Z)-enamides under mild and environmentally friendly conditions with excellent efficiency, even at an ultralow photocatalyst loading (S/C up to 10 000). Furthermore, the method demonstrates scalability, making it well-suited for the large-scale preparation of (Z)-enamides with operational simplicity.