Palladium-Catalyzed Domino Heck/C-H Activation/Decarboxylation: A Rapid Entry to Fused Isoquinolinediones and Isoquinolinones.

A new palladium-catalyzed tandem cyclization of various alkene-tethered aryl iodides has been presented. In this protocol, o-bromobenzoic acids are employed as coupling parters to achieve the insertion of aromatic rings by the cleavage of C(sp2)-Br and decarboxylation, thus assembling various dibenzoisoquinolinediones and dibenzoisoquinolinones. In addition, a seven-membered ring can be constructed by the use of 8-bromo-1-naphthoic acid. Notably, this approach enables regioselective product formation and features broad substrate scope.