Direct Construction of Diverse Polyheterocycles Bearing Pyrrolidinediones via Rh(III)-Catalyzed Cascade C-H Activation/Spirocyclization

Rh(III)-catalyzed cascade oxidative annulation of 2-arylquinazolinones with various maleimides to afford spiroisoindoloquinazolinones bearing pyrrolidinediones is described. Sequential ortho C-H functionalization and spirocyclization via aza-Michael addition result in the formation of both C-C and C-N bonds in a single operation. This atom- and step-economic strategy provides an efficient and novel approach for the syntheses of diverse polyheterocycles bearing pyrrolidinediones, starting from 2-heteroarylquinazolinones and 5-arylpyrazolopyrimidinones, in good to excellent yields.