Fulval

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Structural formula
Structural formula of fulvalene
General
Surname Fulval
other names
  • 1,1'-Bi (2,4-cyclopentadien-1-ylidene) ( IUPAC )
  • Bicyclopentylidene-2,4,2 ', 4'-tetraene
  • Pentafulvalene
  • Bicyclopentadienylidene
  • [5,5 '] bicyclopentadienylidene
Molecular formula C 10 H 8
Brief description

orange liquid

External identifiers / databases
CAS number 91-12-3
PubChem 10908294
ChemSpider 9083553
Wikidata Q415358
properties
Molar mass 128.17 g mol −1
Physical state

liquid

safety instructions
GHS hazard labeling
no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Fulvalen is a chemical compound belonging to the cycloalkenes group . Formally it consists of two cyclopentadiene rings that are linked by a double bond . Fulvalen is isomeric to naphthalene and azulene .

presentation

The first attempt at the synthesis of fulvalene by oxidative coupling of cyclopentadienyl salts with iron (III) chloride led to the discovery of ferrocene .

Fulvalene can be produced from the reaction of cyclopentadiene with butyllithium . A cyclopentadienyl radical is formed as an intermediate and dimerizes . This is then carried oxygen to fulvalene oxidized .

Synthesis of fulvalene

properties

Fulval is an orange liquid. The compound is unstable and easily dimerizes: in addition to the Diels-Alder reaction , which proceeds analogously to the dimerization of cyclopentadiene , it also undergoes [2 + 2] cycloadditions . Electron-poor perchlorfulvalene (C 10 Cl 8 ) is relatively stable . Tetrathiafulvalene (C 6 H 4 S 4 ) is an organic semiconductor .

Individual evidence

  1. ↑ a b A. G. Davies, JRM Giles, J. Lusztyk: The Electron Spin Resonance Spectrum of the Fulvalene Radical Anion . In: J. Chem. Soc. Perkin Trans. 2 1981 , 747-752.
  2. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
  3. ^ TJ Kealy, PL Pauson: A New Type of Organo-Iron Compound . In: Nature 1951 , 168 , 1039.
  4. ↑ A. Escher, W. Rutsch, M. Neuenschwander: Synthesis of pentafulvalene by oxidative coupling of cyclopentadienide using copper (II) chloride . In: Helv. Chim. Acta 1986 , 69 , 1644-1654. doi : 10.1002 / hlca.19860690719
  5. ^ V. Mark: Perchlorofulvalene In: Organic Syntheses . 46, 1966, p. 93, doi : 10.15227 / orgsyn.046.0093 ; Coll. Vol. 5, 1973, p. 901 ( PDF ).
  6. ^ Hans Beyer and Wolfgang Walter : Textbook of Organic Chemistry , 23rd edition, S. Hirzel Verlag, Stuttgart 1998, ISBN 3-7776-0808-4 , p. 425.