Cyclobutadieneiron tricarbonyl is an
organoiron compound with the formula Fe(C4H4)(CO)3. It is a yellow oil that is soluble in organic solvents. It has been used in
organic chemistry as a precursor for
cyclobutadiene, which is an elusive species in the free state.[1]
Preparation and structure
Cyclobutadieneiron tricarbonyl was first prepared in 1965 by Pettit from 3,4-dichlorocyclobutene and
diiron nonacarbonyl:[2][3]
In 1956, Longuet-Higgins and Orgel[8] predicted the existence of transition-metal cyclobutadiene complexes, in which the degenerate eg orbital of cyclobutadiene has the correct symmetry for π interaction with the dxz and dyz orbitals of the proper metal. The compound was synthesized three years after the prediction[9] This case of theory before experiment.[10]
References
^Seyferth, Dietmar (2003). "(Cyclobutadiene)iron Tricarbonyl. A Case of Theory before Experiment". Organometallics. 22: 2–20.
doi:
10.1021/om020946c.
^Cyclobutadiene- and Benzocyclobutadiene-Iron Tricarbonyl Complexes G. F. Emerson, L. Watts, R. Pettit;
J. Am. Chem. Soc.; 1965; 87(1); 131-133.
First Page
^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.
^L. Brener; J. S. Mckennis; R. Pettit (1976). "Cyclobutadiene In Synthesis: endo-Tricyclo[4.4.0.02,5]deca-3,8-diene-7,10-dione". Org. Synth. 55: 43.
doi:
10.15227/orgsyn.055.0043.
^Cyclobutadieneiron Tricarbonyl. A New Aromatic System J. D. Fitzpatrick, L. Watts, G. F. Emerson, R. Pettit
J. Am. Chem. Soc.; 1965, vol. 87, 3254-3255
Abstract
^R. P. Dodge, V. Schomaker, "Crystal Structure of Tetraphenylcyclobutadiene Iron Tricarbonyl", Nature 1960, vol. 186, 798-799.
doi:
10.1038/186798b0