Intramolecular oxazole-olefin Diels–Alder reactions: A review of the last two decades

This comprehensive review focuses on the different synthetic approaches to various heterocycles by means of oxazole-olefin intramolecular Diels–Alder reactions (DARs), which include multicomponent single-step reactions, catalyst involved reactions, intermediate step Diels–Alder reactions, and in situ reactions. The review covered such types of reactions reported from the last two decades. All the discussed intramolecular oxazole comprised olefin cycloaddition approaches are useful for constructing bicyclic, tricyclic, polycyclic heterocyclic compounds, various natural products, including pyridine-containing, cyclopentapyridines, pyrrolopyridines, quinolines, and others.