Cu(II)/Iodine(III) Oxide Dimerization of Heterocyclic Ketene Aminals: Tandem TEMPO Oxidation for the Highly Selective Synthesis of Functionalized 2H-Pyrrolo[1,2-a]imidazol-7(3H)-ones.

This study aimed to develop a novel protocol for the synthesis of 2H-pyrrolo[1,2-a]imidazol-7(3H)-ones (PIDOs) from heterocyclic ketene aminals (HKAs) through an unprecedented cascade reaction by refluxing. Consequently, a series of PIDOs was produced through an amazing oxidative dimerization, followed by sequential cleavage of the C-N and C-C bonds in dimeric HKAs. This formation of PIDOs was accompanied by the formation and cleavage of many bonds. This method is suitable for the parallel construction of bicyclic pyrrolidone-like products.