Copper‐Catalyzed Oxidative Carbamoylation of N‐Arylacrylamides with Hydrazinecarboxamides Leading to 2‐(Oxindol‐3‐yl)acetamides

A tandem radical carbamoylation/cyclization reaction of N‐arylacrylamides with hydrazinecarboxamides has been developed for facile access to 2‐(oxindol‐3‐yl)acetamides, which had been utilized as precursors in the synthesis of natural bioactive pyrrolidinoindolines. In the presence of 1 mol% of copper(II) carbonate and 4 equiv. of tert‐butyl hydroperoxide, a wide range of N‐arylacrylamides underwent highly regioselective carbamoylation with hydrazinecarboxamides followed by 5‐exo‐trig cyclization to afford structurally diverse 2‐(oxindol‐3‐yl)acetamides in moderate to excellent yields.