Asymmetric CH Functionalization of Ferrocene

Abstract Since the milestone discovery of its sandwich‐type scaffold in the early 1950s, ferrocene and its related organometallic compounds have received enormous interest from chemistry, biology, and material communities. The rigid molecular architecture and aromaticity make them relatively stable and applicable as catalysts or ligands for the diverse organic transformations. To date, a wide range of synthetic methodologies for this unique family of organometallic compounds have been developed, given their widespread application in organic synthesis. Among them, the recent direct CH functionalization catalyzed by transition metals provided an atom‐ and step‐economical approach to the structurally diverse ferrocene derivatives. In particular, transition metal‐catalyzed asymmetric CH functionalization of ferrocene has proven an efficient, enantioselective strategy for the synthesis of planar‐chiral ferrocenes. In this article, the recent progress on direct asymmetric CH functionalization of ferrocene derivatives is summarized.