Cascade Reaction by I ₂ /Base‐Promoted Synthesis of Chromeno‐[3,4‐ c ]pyrrol‐4(2 H )‐ones from 2‐Hydroxychalcones and β‐ Enamine Esters

An efficient methodology for the synthesis of a variety of chromeno[3,4‐ c ]pyrrol‐4(2 H )‐ones from 2‐hydroxychalcones and N ‐substituted β ‐enamine esters via I 2 /base promoted Michael addition/cyclization/lactonization/aromatization sequence have been developed, affording the coumarin heterocyclic derivatives in moderate to excellent yields. This approach is a highly efficient and convenient way to get derivatives of chromeno[3,4‐ c ]pyrrol‐4(2 H )‐ones from readily accessible substrates under green reaction conditions.