Cyclic sandwich compounds synthesised for the first time

A new class of cyclic compounds features repeating units of sandwich complexes in closed, circular rings. The German research team that discovered them hope that ‘cyclocenes’ will open the door to new functional organometallic materials.

The isolation of the very first sandwich complex, ferrocene, was a major milestone for organometallic chemistry. Now the team led by Peter Roesky at the Karlsruhe Institute of Technology has synthesised cyclocene compounds containing up to 18 metallocene sandwich units.