Lithium cyclopentadienide is an
organolithium compound
In organometallic chemistry, organolithium reagents are chemical compounds that contain carbon–lithium (C–Li) bonds. These reagents are important in organic synthesis, and are frequently used to transfer the organic group or the lithium atom ...
with the
formula C
5H
5Li. 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
Cyclopentadiene is an organic compound with the formula C5H6.LeRoy H. Scharpen and Victor W. Laurie (1965): "Structure of cyclopentadiene". ''The Journal of Chemical Physics'', volume 43, issue 8, pages 2765-2766. It is often abbreviated CpH beca ...
with
butyllithium:
:C
5H
6 + LiC
4H
9 → LiC
5H
5 + C
4H
10
Because lithium cyclopentadienide is usually handled as a solution, the solvent-free solid is rarely encountered. According to
X-ray crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angle ...
, LiCp is a "polydecker"
sandwich complex, consisting of an infinite chain of alternating Li
+ centers sandwiched between
''μ''-
''η''5:''η''
5-C
5H
5 ligands.
In the presence of amines or ethers, LiCp gives adducts, e.g. (''η''
5-Cp)Li(TMEDA).
[ LiCp is a common reagent for the preparation of ]cyclopentadienyl complex
A cyclopentadienyl complex is a coordination complex of a metal and cyclopentadienyl groups (, abbreviated as Cp−). Cyclopentadienyl ligands almost invariably bind to metals as a pentahapto (''η''5-) bonding mode. The metal–cyclopentadien ...
es.
See also
*Sodium cyclopentadienide
Sodium cyclopentadienide is an organosodium compound with the formula C5H5Na. The compound is often abbreviated as NaCp, where Cp− is the cyclopentadienide anion. Sodium cyclopentadienide is a colorless solid, although samples often are p ...
References
{{Cyclopentadiene complexes
Cyclopentadienyl complexes
Non-benzenoid aromatic carbocycles
Organolithium compounds