Transition‐Metal‐Free Intramolecular Carbene Aromatic Substitution/Büchner Reaction: Synthesis of Fluorenes and [6,5,7]Benzo‐fused Rings

Abstract Intramolecular aromatic substitution and Büchner reaction have been established as powerful methods for the construction of polycyclic compounds. These reactions are traditionally catalyzed by Rh II catalysts with α‐diazocarbonyl compounds as the substrates. Herein a transition‐metal‐free intramolecular aromatic substitution/Büchner reaction is presented. These reactions use readily available N ‐tosylhydrazones as the diazo compound precursors and show wide substrate scope.