Facile Synthesis of Pentamethylcyclopentadienyl Ruthenium Half-Sandwich Complexes by Naphthalene Displacement

Ruthenium half-sandwich complexes are central in a wide range of diverse applications in the field of organometallic chemistry. As such, exploration of their preparation and reactivity is crucial for development of their chemistry. Herein, we present alternative synthetic methods for the preparation of Cp∗Ru(dppm)Cl, Cp∗Ru(dppe)Cl, Cp∗Ru(dppf)Cl, [Cp∗Ru(COD)(MeCN)]BF₄, and [Cp∗Ru(bpy)(MeCN)]BF₄(dppm ≤ 1,2-bis(diphenylphosphino)methane; dppe ≤ 1,2-bis(diphenylphosphino) ethane; dppf ≤ 1,2-bis(diphenylphosphino)ferrocene; COD ≤ 1,5-cyclooctadiene; bpy≤ 2,2′-bipyridine), starting from the easily accessible [Cp∗Ru(η⁶-C₁₀H₈)]BF₄. The single-crystal X-ray structure determinations for [Cp∗Ru(COD)(MeCN)]BF₄, and [Cp∗Ru(bpy)(MeCN)]BF₄ are also presented.