C═C Double Bond Cleavage of 2-Cyanoaryl Acrylamides for the Construction of 3-Hydroxyquinoline-2,4(1 <i>H</i> ,3 <i>H</i> )-diones

An oxone-promoted radical annulation of 2-cyanoaryl acrylamides involving carbon-carbon double bond cleavage has been developed for the construction of 3-hydroxyquinoline-2,4(1<i>H</i>,3<i>H</i>)-diones. Such transformation exhibits good functional group tolerance and scalability. The reaction proceeds through an initial radical cyclization to form a 4-aminoquinolinone intermediate followed by hydroxylation to afford the final product.