Chemical Auxiliary

Ferrocene is an organometallic compound with the formula Fe(C5H5)2. It is the prototypical metallocene, a type of organometallicchemical compound consisting of two cyclopentadienyl rings bound on opposite sides of a central metal atom. Such organometallic compounds are also known as sandwich compounds. The rapid growth of organometallic chemistry is often attributed to the excitement arising from the discovery of ferrocene and its many analogues.

The structure of ferrocene was confirmed by NMR spectroscopy and X-ray crystallography. Its distinctive & quot;sandwich& quot; structure led to an explosion of interest in compounds of d-block metals with hydrocarbons, and invigorated the development of the flourishing study of organometallic chemistry. In 1973 Fischer of the Technische Universit?t München and Wilkinson of Imperial College London shared a Nobel Prize for their work on metallocenes and other aspects of organometallic chemistry.
Reactions
With electrophiles
Ferrocene undergoes many reactions characteristic of aromatic compounds, enabling the preparation of substituted derivatives. A common undergraduate experiment is theFriedel-Crafts reaction of ferrocene with acetic anhydride (or acetyl chloride) in the presence of phosphoric acid as a catalyst.
Important reactions of ferrocene with electrophiles and other reagents.
Lithiation[edFerrocene reacts readily with butyl lithium to give 1,1& acute;-dilithioferrocene, which in turn is a versatile nucleophile. But reaction of Ferrocene with t-BuLi produces monolithioferrocene only. These approaches are especially useful methods to introduce main group functionality, e.g. using S8, chlorophosphines, chlorosilanes. The strained compounds undergo ring-opening polymerization.