Difference between revisions 6001642 and 6001643 on simplewiki

{{chembox
| verifiedrevid = 390057418
| ImageFileL1 = Ferrocene.svg
| ImageSizeL1 = 80 px
| ImageFileR1 = Ferrocene-from-xtal-3D-balls.png
| ImageSizeR1 = 120 px
| ImageFile2 = Photo of Ferrocene (powdered).JPG
| ImageSize2 = 220 px
(contracted; show full)tives have been prepared. For example, the penta(ferrocenyl)cyclopentadienyl ligand,<ref>{{cite journal|author=Y. Yu, A.D. Bond, P. W. Leonard, K. P. C. Vollhardt, G. D. Whitener| title=Syntheses, Structures, and Reactivity of Radial Oligocyclopentadienyl Metal Complexes: Penta(ferrocenyl)cyclopentadienyl and Congeners| journal= [[Angewandte Chemie International Edition]]| volume =45|issue=11| pages= 1794–1799|year=2006|pmid=16470902| doi=10.1002/anie.200504047}}</ref> features a cyclopentadien
eyl anion derivatised with five ferrocene substituents.
[[Image:Penta(ferrocenyl)cyclopentadienyl.png|500px|center|Penta(ferrocenyl)cyclopentadienyl ligand]]

[[Image:Hexaferrocenylbenzene-3D-sticks.png|200px|thumb|right|Structure of hexaferrocenylbenzene]]

In '''hexaferrocenylbenzene''', C<sub>6</sub>[(&eta;<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>)Fe(&eta;<sup>5</sup>-C<sub>5</sub>H<sub>5</sub>)]<sub>6</sub>, all six positions on a [[benzene]] molecule have ferrocenyl substituents ('''R''').<ref name = "hexaferrocenylbenzene">{{cite journal|title=Hexaferrocenylbenzene|author= Yong Yu, Andrew D. Bond, Philip W. Leonard, Ulrich J. Lorenz, Tatiana V. Timofeeva, K. Peter C. Vollhardt, Glenn D. Whitener and Andrey A. Yakovenko| journal=[[Chemical Communications|Chem. Commun.]]|issue=24| year=2006| pages= 2572–2574|pmid=16779481 |doi=10.1039/b604844g}}</ref> [[X-ray diffraction]] analysis of this compound confirms that the cyclopentadienyl ligands are not co-planar with the benzene core but have alternating [[dihedral angle]]s of +30° and −80°. Due to steric crowding the ferrocenyls are slightly bent with angles of 177° and have elongated C-Fe bonds. The quaternary cyclopentadienyl carbon atoms are also [[pyramidalization|pyramidalized]].<ref>Also, the benzene core has a [[chair conformation]] with dihedral angles of 14° and displays [[bond length]] alternation between 142.7 [[picometer|pm]] and 141.1 pm, both indications of steric crowding of the substituents.</ref>

The synthesis of hexaferrocenylbenzene has been reported using [[Negishi coupling]] of hexaiodidobenzene and diferrocenylzinc, using [[tris(dibenzylideneacetone)dipalladium(0)]] as [[catalyst]], in [[tetrahydrofuran]]:<ref>{{cite journal |author=Yong Yu, Andrew D. Bond, Philip W. Leonard, Ulrich J. Lorenz, Tatiana V. Timofeeva, K. Peter C. Vollhardt, Glenn D. Whitener and Andrey A. Yakovenko |doi=10.1039/b604844g |title=Hexaferrocenylbenzene |year=2006 |journal=[[Chemical Communications|Chem. Commun.]] |pages=2572-2574 |pmid=16779481 |issue=24}}
</ref name = "hexaferrocenylbenzene" />
:[[Image:Hexaferrocenylbenzene.png|400px|Hexaferrocenylbenzene synthesis by Negishi coupling]]
The [[yield (chemistry)|yield]] is only 4%, which suggests that there isis further evidence consistent with substantial [[steric strain|steric]] crowding around the arene core.
{{clear}}

==References==
{{reflist|2}}

{{commonscat|ferrocene}}

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