Difference between revisions 6001538 and 6001539 on simplewiki

{{Chembox new
| ImageFileL1 = Ferrocene-2D.png
| ImageSizeL1 = 80 px
| ImageFileR1 = Ferrocene-3D-balls-B.png
| ImageSizeR1 = 120 px
| IUPACName = ferrocene, bis(η<sup>5</sup>-cyclopentadienyl)iron
| OtherNames = ferrocene, iron cyclopentadienyl 
| Section1 = {{Chembox Identifiers
(contracted; show full)metallic chemistry.  In 1973 [[Ernst Otto Fischer|Fischer]] of the [[Ludwig-Maximilians-Universität München]] and [[Geoffrey Wilkinson|Wilkinson]] of [[Imperial College London]] shared a Nobel Prize  with for their work on metallocenes and other aspects of organometalic chemistry.<ref>{{cite web |url=http://nobelprize.org/nobel_prizes/chemistry/laureates/1973/press.html |title= Press Release: The Nobel Prize in Chemistry 1973 |year= 1973 |publisher= The Royal Swedish Academy of Sciences}}</ref>
  Ferrocene is efficiently prepared by the reaction of sodium cyclopentadienyl with anhydrous [[iron(II) chloride|ferrous chloride]] in ethereal solvents:
:2 NaC<sub>5</sub>H<sub>5</sub>  +  FeCl<sub>2</sub>   →   Fe(C<sub>5</sub>H<sub>5</sub>)<sub>2</sub>  +  2 NaCl

==Bonding and Structure==
The iron atom in ferrocene is normally assigned to the +2 oxidation state, as can be shown using [[Mössbauer spectroscopy]]. Each cyclopentadienyl (Cp) ring is then allocated a single negative charge, bringing the number of π-electrons on each ring to six, and thus making them [[aromaticity|aromatic]].  These twelve electrons (six from each ring) are then shared with the metal ''via'' covalent bonding, which, when combined with the six ''d''(contracted; show full)| temperature(K)
| 298
| 323
| 353
|}

==Chemical properties==

⏎
Ferrocene is efficiently prepared by the reaction of sodium cyclopentadienyl with anhydrous [[iron(II) chloride|ferrous chloride]] in ethereal solvents:
:2 NaC<sub>5</sub>H<sub>5</sub>  +  FeCl<sub>2</sub>   →   Fe(C<sub>5</sub>H<sub>5</sub>)<sub>2</sub>  +  2 NaCl⏎
⏎
===Reaction with electrophiles===
⏎
⏎
Ferrocene undergoes many reactions characteristic of aromatic compounds, enabling the preparation of substituted derivatives.  A common undergraduate experiment is the [[Friedel-Crafts reaction]] of ferrocene with [[acetic anhydride]] (or [[acetyl chloride]]) in the presence of [[phosphoric acid]] as a catalyst.  The preparation of phosphorus derivatives of ferrocenes are illustrative.  In the presence of [[aluminium chloride]]  Me<sub>2</sub>NPCl<sub>2</sub> and ferrocene react to give ferrocenyl dichloro[[phosphine]],<ref>{{cite journal
 | title = Ferrocene derivatives. 27. Ferrocenyldimethylphosphine
 | author = G.R. Knox, P.L. Pauson and D. Willison
 | journal = Organometallics
 | volume = 11
 | issue = 8
 | pages = 2930 &ndash; 2933
 | year = 1992
 | doi = 10.1021/om00044a038
}}</ref>  ⏎
⏎
while treatment with phenyldichlorophosphine under similar conditions forms ''P,P''-diferrocenyl-''P''-phenyl phosphine.<ref>{{cite journal
 | author = G.P. Sollott, H.E. Mertwoy, S. Portnoy and J.L. Snead
 | title = Unsymmetrical Tertiary Phosphines of Ferrocene by Friedel-Crafts Reactions. I. Ferrocenylphenylphosphines 
 | journal = J. Org. Chem.
 | year = 1963 
 | volume = 28 
 | pages = 1090 &ndash; 1092
 | doi = 10.1021/jo01039a055⏎
⏎
}}⏎
⏎
</ref>  ⏎
⏎
In common with [[anisole]] the reaction of ferrocene with P<sub>4</sub>S<sub>10</sub> forms a dithiadiphosphetane disulfide.<ref>{{cite journal
 | title = 2,4-Diferrocenyl-1,3-dithiadiphosphetane 2,4-disulfide; structure and reactions with catechols and [PtCl<sub>2</sub>(PR<sub>3</sub>)<sub>2</sub>](R = Et or Bun)
 | author = Mark R. St. J. Foreman, Alexandra M. Z. Slawin and J. Derek Woollins
 | journal = J. Chem. Soc., Dalton Trans., 
 | year = 1996
 | pages =  3653 &ndash; 3657
 | doi = 10.1039/DT9960003653⏎
⏎
}}</ref>

[[Image:FcGen'l.png|center|400px|thumb|center|Important reactions of ferrocene with electrophiles and other reagents.]]

<br clear = left/>⏎
⏎
===Lithiation===
⏎
⏎
Ferrocene reacts readily with [[butyl lithium]] to give 1,1'-dilithioferrocene, which in turn is a versatile [[nucleophile]]. It has been reported that the reaction of 1,1'-dilithioferrocene with [[selenium]] diethyl[[dithiocarbamate]] forms a strained ferrocenophane where the two cyclopentadienyl ligands are linked by the selenium atom.<ref>Ron Rulkens, Derek P. Gates, David Balaishis, John K. Pudelski, Douglas F. McIntosh, Alan J. Lough, and Ian Manners, ''J. Am. Chem. Soc.'', 1997, '''119''', 10976</ref> This ferrocenophane can be converted to a polymer by a [[thermal]] [[ring-opening polymerization]] (ROP) to form poly(ferrocenyl selenide). Likewise by the reaction of [[silicon]] and [[phosphorus]] linked ferrocenophanes the poly(ferrocenylsilane)s and poly(ferrocenylphosphines)s can be obtained.<ref>Paloma Gómez-Elipe, Rui Resendes, Peter M. Macdonald, and Ian Manners, ''J. Am. Chem. Soc.,'' 1998, '''120''', 8348</ref><ref>Timothy J. Peckham, Jason A. Massey, Charles H. Honeyman, and Ian Manners, ''Macromolecules'', 1999, ''32'', 2830</ref>

[[Image:Ferrocenelithiation.png|thumb|450px450px|thumb|centrer|A diagram showing the litiation of ferrocene with BuLi, and then the reactions of the dilithioferrocene with a series of electrophiles]]

===Redox chemistry===
(contracted; show full)[[ja:フェロセン]]
[[pl:Ferrocen]]
[[ru:Ферроцен]]
[[fi:Ferroseeni]]
[[sv:Ferrocen]]
[[tr:Ferrosen]]
[[ur:Ferrocene]]
[[zh:二茂铁]]