Syntheses of Acridones via Copper(II)-Mediated Relay Reactions from o-Aminoacetophenones and Arylboronic Acids.

The reaction of o-aminoacetophenones and arylboronic acids catalyzed by copper(II) salts in the presence of pyridine under an O2 atmosphere provides a general and efficient one-pot preparation of biologically interesting acridones. This relay reaction comprises an intermolecular Suzuki cross-coupling, intramolecular oxidative C(sp3)-H amination, and C(sp2)-H activation with simultaneous rearrangement of the generated isatin intermediates. This strategy tolerates both electron-donating and -withdrawing functionalities to afford various acridones in good to excellent yields.