Rhodium(III)‐Catalyzed ortho‐Alkenylation of Anilides with Maleimides

Abstract

AbstractA rhodium(III)‐catalyzed ortho‐alkenylation of substituted anilides with maleimides providing 3‐arylated maleimides in good to excellent yields is described. In the reaction, a minor amount of Michael‐type addition product, 3‐arylated succinimides, was also observed. Later, 3‐arylated succinimides was converted into 3‐arylated maleimides in the presence of diisopropyl azodicarboxylate and K2CO3. Generally, a Michael‐type 3‐arylated succinimides was observed in the reaction of maleimides with substituted aromatics via C‐H bond activation. In the present reaction, unusually, a Heck‐type alkenylated product was observed in the major amount. A possible reaction mechanism was proposed and supported by the deuterium labelling studies and computational experiments. The mechanistic investigation and DFT calculations revealed that the time interval for the regeneration of Rh(I) to Rh(III) could be the factor for the observation of a minor ortho alkylated aromatics which was formed via a redox neutral Rh(III) version.