Chemists in the US and Denmark have made a molecule that many had thought would be impossible to synthesise.

Peter Vollhardt at University of California at Berkeley, US, and colleagues made the molecule hexaferrocenylbenzene for the first time. The molecule consists of a benzene ring with six bulky ferrocene groups attached. This gives the molecule an extremely crowded structure, which the researchers say makes it very difficult to synthesise.

The reluctance of the molecule to incorporate six bulky substituents keeps the yield of the reaction low (less than five percent), said Vollhardt. 

Vollhardt claims, 'hexaferrocenylbenzene has been sought for decades.' He said it has attracted great interest because of its potential uses in electronics, magnetism, optics and catalysis. Vollhardt says the molecule might find application as a molecular gear in a nanomachine, or as a starting point for other molecules of even greater complexity.

Vollhardt and colleagues are working on improving the yield of the synthesis and exploring hexaferrocenylbenzene's chemistry.

Michael Spencelayh