Preparation of Nitrogen‐Substituted Ferrocene Derivatives by Aza‐Wittig Methodologies

Several methodologies based on the aza‐Wittig reaction, mainly developed by our research group, have been used for the preparation of a wide variety of ferrocenes containing nitrogen functionalities. Syntheses of mononuclear and nitrogen‐rich multinuclear ferrocenophanes, ferrocenyl‐pyrazine, quinoline, imidazole and oxazole derivatives have been performed through aza‐Wittig reactions and by aza‐Wittig/heterocumulene‐mediated annulation, aza‐Wittig/electrocyclic ring‐closure and aza‐Wittig/intramolecular halide displacement methodologies.