Palladium-Catalyzed Double-Isocyanide Insertion via Oxidative N-O Cleavage of Acetyl Oximes: Syntheses of 2H-Pyrrol-2-imines

The palladium-catalyzed reaction of acetyl oximes with isocyanides was developed for the synthesis of 2H-pyrrol-2-imines. The key steps were (i) generation of an enamido-palladium(II) species, (ii) migratory double-isocyanide insertion, and (iii) cyclization. The scope of the synthesis of some 2H-pyrrol-2-imines was extended to the synthesis 1H-pyrrole-2,3-dione/1H-benzo[g]indole-2,3-dione derivatives via acid hydrolysis in a sequential one-pot manner.