Rearrangement of Quinoxalin‐2‐ones when Exposed to Enamines Generated in situ from Ketones and Ammonium Acetate: Method for the Synthesis of 1‐(Pyrrolyl)benzimidazolones.

The reaction of 3-benzoylquinoxalin-2(1H)-ones with enamines (generated in situ from ammonium acetate and the corresponding methylaryl(hetaryl)ketones) proceeds smoothly to give the corresponding substituted 1-(pyrrolyl)benzimidazolone derivatives in moderate yields through the novel rearrangement of 3-benzoylquinoxalin-2(1H)-ones involving a dual cleavage of the C3═N4 and C2-C3 bonds under mild conditions.