A novel domino synthesis of quinazolinediones by palladium-catalyzed double carbonylation.

Combining commercially available bromoanilines and bromobenzonitriles in a novel double carbonylation process allows for a straightforward synthesis of isoindolo[1,2-b]quinazoline-10,12-diones. At least five different CC and/or CN bonds are selectively formed in this 3-component reaction, which likely proceeds through sequential carbonylation-cyclization-isomerisation-carbonylation steps. Notably, two molecules of CO are inserted in this highly efficient palladium-catalyzed process.