Recent Developments in Synthetic Methodologies for Isochromenes

Isochromenes, oxygen-containing bicyclic compounds, have gained significant attention in organic synthesis due to their versatile reactivity and prominence in biologically active natural products. This review highlights recent developments in the synthesis of isochromenes, with a focus on efficient and selective methodologies. Traditional metal-catalyzed intramolecular ring-closure reactions have been the cornerstone for isochromene formation, but recent efforts have expanded to include new strategies that enhance functionalization and scalability. By examining key advancements in the field, this article provides a critical assessment of the current state of the art involving isochromene synthesis and its ongoing challenges.