Bis(fulvalene)diiron
Bis(fulvalene)diiron is the organoiron complex with the formula (CH-CH)Fe. Structurally, the molecule consists of two ferrous centers sandwiched between fulvalene dianions. The compound is an orange solid with lower solubility in benzene than ferrocene. Its structure has been verified by X-ray crystallography. The compound has attracted some interest for its redox properties. Preparation. It was first prepared by Ullmann coupling of 1,1'-diiodoferrocene using copper but subsequent work produces the complex is 20-40% yield from dilithiofulvalene and ferrous chloride: