One-Pot Synthesis of 3-Iminoisoindolinones by a Rhodium(III)-Catalyzed and Methanol-Assisted C-H Cyanation-Cyclization Cascade with N-Alkoxyl Transfer

Herein, we disclose the Rh-III-catalyzed and MeOH-assisted direct C-H functionalization of simple N-alkoxybenzamides with N-cyano-N-phenyl-p-toluenesulfonamide (NCTS) in a one-pot cascade synthesis of 3-iminoisoindolinones with excellent substrate/functional group tolerance. Experimental studies reveal that the versatile reaction comprises a regioselective C-H cyanation and subsequent intramolecular cyclization along with N-alkoxyl transfer. Furthermore, the synthetic application of the obtained products to rapidly build other important structural motifs, such as lactams and phthalazinones, has also been demonstrated in subsequent derivatization reactions.