Difference between revisions 6001625 and 6001626 on simplewiki

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| ImageFileL1 = Ferrocene-2D.png
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| ImageFile2 = Photo of Ferrocene (powdered).JPG
(contracted; show full) the expected way: electron withdrawing group such as a carboxylic acid shift the potential in the [[anodic]] direction (''i.e.'' made more positive), whereas electron releasing groups such as [[methyl]] groups shift the potential in the [[cathodic]] direction (more negative). Thus, decamethylferrocene is much more easily oxidised than ferrocene. Ferrocene is often used as an [[internal standard]] for calibrating redox potentials in non-aqeous [[electrochemistry]].

==Stereochemistry==

[[Image:Planar chiral ferrocene derivative.PNG|thumb|right|A planar chiral ferrocene derivative]]⏎
A variety of substitution patterns are possible with ferrocene including substition at one or both of the rings. The most common substitution patterns are 1-substituted (one substituent on one ring) and 1,1'-disubstituted (one substituent on each ring). Usually the rings rotate freely, which simplifies the isomerism. Disubstituted ferrocenes can exist as either 1,2- and, 1.3- or 1,1'- isomers, none of which are not interconvertible. Ferrocenes that are asymetrically disubstituted on one ring are chiral, e.g.  - for example [CpFe(EtC<sub>5</sub>H<sub>3</sub>Me).] is chiral but [CpFe(C<sub>5</sub>H<sub>3</sub>Me<sub>2</sub>)] is achiral.  This [[planar chirality]] arises despite no single atom being a [[stereocenter|stereogenic centre]].  The substituted ferrocene shown at right (a 4-(dimethylamino)pyridine derivative) has been shown to be effective when used for the [[kinetic resolution]] of [[racemic]] [[secondary alcohol]]s.<ref>{{cite journal |last1= Ruble|first1= J. C.|last2= Latham|first2= H. A.|last3= Fu|first3= G. C.|year= 1997|title= Effective Kinetic Resolution of Secondary Alcohols with a Planar-Chiral Analogue of 4-(dimethylamino)pyridine. Use of the Fe(C<sub>5</sub>Ph<sub>5</sub>) Group in Asymmetric Catalysis|journal= [[J. Am. Chem. Soc.]]|volume= 119|issue= 6|pages= 1492-1493|url= |doi= 10.1021/ja963835b}}</ref>

==Applications of ferrocene and its derivatives==
Ferrocene and its numerous derivatives have no large-scale applications, but have many niche uses that exploit the unusual structure (ligand scaffolds, pharmaceutical candidates), robustness (anti-knock formulations, precursors to materials), and redox (reagents and redox standards).

===Fuel additives===
(contracted; show full)[[ru:Ферроцен]]
[[fi:Ferroseeni]]
[[sv:Ferrocen]]
[[th:เฟอร์โรซีน]]
[[tr:Ferrosen]]
[[uk:Фероцен]]
[[ur:Ferrocene]]
[[zh:二茂铁]]