Synthesis and Characterization of a Rhenanaphthalene Isomer

Exploration of organometallic metallacycles has led to the development of various polycyclic compounds with fascinating structures, which could be used as functional materials. In this work, a new rhenanaphthalene isomer was isolated from the reaction of ReH5(PMe2Ph)3 with o‐ethynylphenyl alkyne in the presence of excess HCl. Its structure was then identified using the single‐crystal X‐ray diffraction and NMR spectroscopy. DFT studies suggest that its formation involves two protonation reactions and two migration reactions. This new rhenanaphthalene isomer enriches the family of metallacycles. A new rhenanaphthalene isomer was isolated from the reaction of ReH5(PMe2Ph)3 with o‐ethynylphenyl alkyne in the presence of excess HCl. Its formation may involve two protonation reactions and two migration reactions.