Redox-neutral rhodium(III)-catalyzed chemo- and regiospecific [4 + 1] annulation between benzamides and alkenes for the synthesis of functionalized isoindolinones.

Herein, using electron-deficient alkenes embedded with an oxidizing function/leaving group as a rare and nontraditional C1 synthon, we have achieved the redox-neutral Rh(III)-catalyzed chemo- and regioselective [4 + 1] annulation of benzamides for the synthesis of functionalized isoindolinones. This method features broad substrate scope, good to excellent yields, excellent chemo- and regioselectivity, good tolerance of functional groups and mild external-oxidant-free conditions.