How was the first stable copper metallocene made?

How was the first stable copper metallocene made?

Chemists build the long‑missing copper “sandwich” molecule Researchers have synthesized an isolable copper metallocene — a long‑sought inorganic “sandwich” in which a copper atom sits between two cyclopentadienyl rings. The team used very bulky cyclopentadienyl ligands that act as a molecular…

After 70 years, chemists have "completed the set" of 3D transition metal metallocenes by synthesizing the first stable copper "sandwich" molecule. Using bulky molecular shields, researchers created these blue-green crystals, closing a fundamental gap dati