Trichloroisocyanuric Acid Induced Chlorine Radical Cascade Chlorination­/Carbocyclization of Acrylamides: Constructing Chlorinated Oxindoles by C–Cl and C–C Bond-Forming Reactions

A metal- and additive-free strategy for the synthesis of oxindoles has been achieved through a chlorine radical-induced cascade chlorination/carbocyclization of N-aryl acrylamides. Trichloroiso­cyanuric acid (TCCA) is used as both radical initiator and chlorine source. A wide range of substrates can be applied in this process to directly afford chlorinated oxindoles via C–Cl and C–C bond formation.