Iron‐Catalyzed [2+2+2] Cycloadditions for the Construction of Aromatic and Heteroaromatic Rings

In this review, the state-of-the-art of iron-catalyzed [2+2+2] cycloadditions applied to the formation of benzene, pyridine, and phosphabenzene derivatives is described. For decades important efforts have been made to highlight the role of iron as a powerful tool in catalysis, and this work summarizes the scope of iron-catalyzed systems for the development of new, eco-friendly, inexpensive, and practical processes for the synthesis of (hetero)aromatic rings.