Iron: A Worthy Contender in Metal Carbene Chemistry

Carbene transfer reactions hold a pivotal role in organic synthesis, allowing the prompt construction of complex molecules from accessible reagents. Iron complexes emerged as promising catalysts for this reaction, rivaling noble metals' reactivity with improved environmental sustainability and lower costs. Herein, we thoroughly examine the development of iron-catalyzed methodologies in the last 30 years, showcasing its broad reactivity and room for further improvement. Aside from the well-known iron complexes of tetrapyrrolic ligands, recent developments on other iron catalysts are emphasized.