Weak Coordinating Carboxylate Directed Rhodium(III)-Catalyzed C-H Activation: Switchable Decarboxylative Heck-Type and [4 + 1] Annulation Reactions with Maleimides.

A weakly coordinating carboxylate directing group assisted C-H activation with maleimides leading to novel and switchable decarboxylative Heck-type and [4 + 1] annulation products catalyzed by Rh(III) has been reported. In these reactions, solvents play a vital role in switching the selectivity. An aprotic solvent, THF, leads to the decarboxylative Heck-type product while the protic solvent, TFE, results in the [4 + 1] annulation product. The methodology shows high functional group tolerance.