Lithium cyclopentadienide
Lithium cyclopentadienide is an organolithium compound with the formula C5H5Li. The compound is often abbreviated as LiCp, where Cp− is the cyclopentadienide anion. Lithium cyclopentadienide is a colorless solid, although samples often are pink owing to traces of oxidized impurities.Preparation, structure and reactions
Lithium cyclopentadienide is commercially available as a solution in THF. It is prepared by treating cyclopentadiene with butyllithium:
Crystalline solvent-free LiCp, which is rarely encountered, is a "polydecker" sandwich complex, consisting of an infinite chain of alternating Li+ centers sandwiched between μ-η5:η5-C5H5 ligands. In the presence of amines or ethers, LiCp gives adducts, e.g. Li. LiCp is a common reagent for the preparation of cyclopentadienyl complexes.
