Cyclobutadieneiron tricarbonyl

Cyclobutadieneiron tricarbonyl
Cyclobutadieneiron tricarbonyl
Properties
Molecular formula (C4H4)Fe(CO)3
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Cyclobutadieneiron tricarbonyl or (C4H4)Fe(CO)3 is an organometallic complex of cyclobutadiene and an iron metal carbonyl. The chemical compound is used in organic chemistry as a precursor for cyclobutadiene. It was first prepared in 1965 by Rowland Pettit starting from cyclooctatetraene [1] [2] [3] :

Cyclobutadieneiron tricarbonyl Synthesis

Cyclooctatetraene is chlorinated to the [4.2.0]-bicyclic compound which reacts further with the alkyne dimethyl acetylenedicarboxylate in a Diels-Alder reaction followed by a reverse-DA reaction by pyrolysis at 200°C releasing cis-dichlorocyclobutene.

This compound reacts with di-iron nonacarbonyl (obtained from photolysis of iron pentacarbonyl) to Cyclobutadieneiron tricarbonyl.

Cyclobutadieneiron tricarbonyl displays aromaticity as evidenced by some of its reactions which can be classified as electrophilic aromatic substitution [4] :

Cyclobutadieneiron tricarbonyl Reactions

It reacts in Friedel-Crafts acylation with acetyl chloride and aluminium chloride to the acyl derivative 2, with formaldehyde and hydrochloric acid to the chloromethyl derivative 3, in a Vilsmeier-Haack reaction with N-methylformanilide and phosphorus oxychloride to the formyl 4 and in a Mannich reaction to amine derivative 4

The reaction mechanism is identical to that of EAS:

Cyclobutadieneiron tricarbonyl EAS reactionmechanism

References

  1. ^ Cyclobutadiene- and Benzocyclobutadiene-Iron Tricarbonyl Complexes G. F. Emerson, L. Watts, R. Pettit; J. Am. Chem. Soc.; 1965; 87(1); 131-133. First Page
  2. ^ Cis-dichlorocyclobutene , Organic Syntheses, Coll. Vol. 6, p.422 (1988); Vol. 50, p.36 (1970) Article.
  3. ^ Iron, tricarbonyl (η4-1,3-cyclobutadiene)- R. Pettit and J. Henery Organic Syntheses, Coll. Vol. 6, p.310 (1988); Vol. 50, p.21 (1970) Link
  4. ^ Cyclobutadieneiron Tricarbonyl. A New Aromatic System J. D. Fitzpatrick, L. Watts, G. F. Emerson, R. Pettit J. Am. Chem. Soc.; 1965; 87(14); 3254-3255 Abstract

Further reading

  • P. D. Harvey, W. P. Schaefer, H. B. Gray, D. F. R. Gilson, I. S. Butler (1988). "Structure of tricarbonyl(η4-cyclobutadienyl)iron(0) at −45 °C". Inorg. Chem. 27 (1): 57–59. doi:10.1021/ic00274a013. 

Wikimedia Foundation. 2010.

См. также в других словарях:

  • Iron pentacarbonyl — Chembox new Name = Iron pentacarbonyl ImageFileL1 = Fe(CO)5.png ImageSizeL1 = 150px ImageNameL1 = Iron carbonyl ImageFileR1 = Iron pentacarbonyl 3D vdW.png ImageSizeR1 = 120px ImageNameR1 = Iron carbonyl IUPACName = pentacarbonyliron(0)… …   Wikipedia

  • Organoiron chemistry — is the chemistry of organometallic compounds containing a carbon to iron chemical bond.[1][2] Organoiron compounds are relevant in organic synthesis as reagents such as iron pentacarbonyl, diiron nonacarbonyl and disodium tetracarbonylferrate.… …   Wikipedia

  • Cyclobutadiene — IUPAC name …   Wikipedia

  • Organometallic chemistry — n Butyllithium, an organometallic compound. Four lithium atoms are shown in purple in a tetrahedron, and each lithium atom is bound to a butyl group (carbon is black, hydrogen is white). Organometallic chemistry is the study of chemical compounds …   Wikipedia

  • Diiron nonacarbonyl — Diiron nonacarbonyl …   Wikipedia


Поделиться ссылкой на выделенное

Прямая ссылка:
Нажмите правой клавишей мыши и выберите «Копировать ссылку»