Furan

• Formula: C₄H₄O
• Molecular weight: 68.0740
• IUPAC Standard InChI: InChI=1S/C4H4O/c1-2-4-5-3-1/h1-4H Copy

  
• IUPAC Standard InChIKey: YLQBMQCUIZJEEH-UHFFFAOYSA-N Copy
• CAS Registry Number: 110-00-9
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Other names: Divinylene oxide; Furfuran; Oxacyclopentadiene; Oxole; Tetrole; Furane; Furfurane; NCI-C56202; Rcra waste number U124; UN 2389; 1,4-Epoxy-1,3-butadiene
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• Information on this page:
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
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  • Gas Chromatography
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Gas phase ion energetics data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to C₄H₄O⁺ (ion structure unspecified)

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₄H₃O^- +  =

By formula: C₄H₃O^- + H⁺ = C₄H₄O

Vibrational and/or electronic energy levels

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Takehiko Shimanouchi

Symmetry:   C_2ν     Symmetry Number σ = 2

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Gas phase ion energetics data, Vibrational and/or electronic energy levels, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

van Beelen, Koblenz, et al., 2004
van Beelen, E.S.E.; Koblenz, T.A.; Ingemann, S.; Hammerum, S., Experimental and theoretical evaluation of proton affinities of furan, the methylphenols, and the related anisoles, J. Phys. Chem. A, 2004, 108, 2787. [all data]

Klapstein, MacPherson, et al., 1990
Klapstein, D.; MacPherson, C.D.; O'Brien, R.T., The photoelectron spectra and electronic structure of 2-carbonyl furans, Can. J. Chem., 1990, 68, 747. [all data]

Veszpremi, Nyulaszi, et al., 1987
Veszpremi, T.; Nyulaszi, L.; Nagy, J., Ultraviolet photoelectron spectroscopy and quantum-mechanical study of alkyl- and trimethylsilyl-furanes, J. Organomet. Chem., 1987, 331, 175. [all data]

Arimura and Yoshikawa, 1984
Arimura, M.; Yoshikawa, Y., Ionization efficiency and ionization energy of cyclic compounds by electron impact, Mass Spectrosc. (Tokyo), 1984, 32, 375. [all data]

Klasinc, Sabljic, et al., 1982
Klasinc, L.; Sabljic, A.; Kluge, G.; Rieger, J.; Scholz, M., Chemistry of excited states. Part 13. Assignment of lowest .PI.-ionizations in photoelectron spectra of thiophen, furan, and pyrrole, J. Chem. Soc. Perkin Trans. 2, 1982, 539. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Galasso, Klasinc, et al., 1981
Galasso, V.; Klasinc, L.; Sabluic, A.; Trinajstic, N.; Pappalardo, G.C.; Steglich, W., Conformation and photoelectron spectra of 2-(2-Furyl)pyrrole and 2-(2-tThienyl)pyrrole, J. Chem. Soc. Perkin Trans. 2, 1981, 127. [all data]

Willett and Baer, 1980
Willett, G.D.; Baer, T., Thermochemistry and dissociation dynamics of state-selected C₄H₄X ions. 2. Furan 3-butyn-2-one, J. Am. Chem. Soc., 1980, 102, 6769. [all data]

Tedder and Vidaud, 1980
Tedder, J.M.; Vidaud, P.H., Charge exchange mass spectra of thiophene, pyrrole and furan, J. Chem. Soc. Faraday Trans. 2, 1980, 76, 1516. [all data]

Holmes and Terlouw, 1979
Holmes, J.L.; Terlouw, J.K., Structures of [C₄H₄O]⁺ ions produced from 2- and 4-pyrone, J. Am. Chem. Soc., 1979, 101, 4973. [all data]

Van Veen, 1976
Van Veen, E.H., Triplet π-π^* transitions in thiophene, furan and pyrrole by low-energy electron-impact spectroscopy, Chem. Phys. Lett., 1976, 41, 535. [all data]

Aloisi, Santini, et al., 1975
Aloisi, G.; Santini, S.; Savelli, G., Molecular complexes of heteroaromatic five membered ring compounds with tetracyanoethylene. Charge transfer spectra, equilibrium constants and ionization potentials of the donors, J. Chem. Soc. Faraday Trans. 1, 1975, 70, 2045. [all data]

Thorstad and Undheim, 1974
Thorstad, O.; Undheim, K., Mass spectrometry of onium compounds. XXIV. Ionisation potential in structure analysis of pyridodiazo-oxides, Chem. Scr., 1974, 6, 222. [all data]

Linda, Marino, et al., 1971
Linda, P.; Marino, G.; Pignataro, S., A comparison of sensitivities to substituent effects of five- membered heteroaromatic rings in gas phase ionization, J. Chem. Soc. B, 1971, 1585. [all data]

Derrick, Asbrink, et al., 1971
Derrick, P.J.; Asbrink, L.; Edqvist, O.; Jonsson, B.-O.; Lindholm, E., Rydberg series in small molecules. X. Photoelectron spectroscopy and electronic structure of furan, Intern. J. Mass Spectrom. Ion Phys., 1971, 6, 161. [all data]

Potapov and Bazhenov, 1970
Potapov, V.K.; Bazhenov, B.A., The photionization of pyrrole, furan, and thiophene, High Energy Chem., 1970, 505, In original 553. [all data]

Johnstone, Mellon, et al., 1970
Johnstone, R.A.W.; Mellon, F.A.; Ward, S.D., Online acquisition of ionization efficiency data, Intern. J. Mass Spectrom. Ion Phys., 1970, 5, 241. [all data]

Baker, Betteridge, et al., 1970
Baker, A.D.; Betteridge, D.; Kemp, N.R.; Kirby, R.E., Application of photoelectron spectrometry to pesticide analysis. Photoelectron spectra of fivemembered heterocycles and related molecules, Anal. Chem., 1970, 42, 1064. [all data]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]

Zykov, Erchak, et al., 1983
Zykov, B.G.; Erchak, N.P.; Khvostenko, V.I.; Lukevits, E.; Matorykina, V.F.; Asfandiarov, N.L., Photoelectron spectra of furylsilanes and their carbon analogs, J. Organomet. Chem., 1983, 253, 301. [all data]

Bock and Roth, 1983
Bock, H.; Roth, B., Radical ions. 49. Redox reactions of some thiophene derivatives, Phosphorus Sulfur, 1983, 14, 211. [all data]

Kobayashi, Kubota, et al., 1982
Kobayashi, T.; Kubota, T.; Ezumi, K.; Utsunomiya, C., Photoelectron angular distribution study of some isoxazoles combined with perturbation theoretic approach, Bull. Chem. Soc. Jpn., 1982, 55, 3915. [all data]

Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [all data]

Schweig and Thiel, 1974
Schweig, A.; Thiel, W., Photoionization cross sections: He I- and He II-photoelectron spectra of homologous oxygen and sulphur compounds, Mol. Phys., 1974, 27, 265. [all data]

Mommers, Burgers, et al., 1984
Mommers, A.A.; Burgers, P.C.; Holmes, J.L.; Terlouw, J.K., Isomeric [C₃H₄]⁺ ions: Their identification and generation in dissociative ionizations, Org. Mass Spectrom., 1984, 19, 7. [all data]

Grabowski and Owusu
Grabowski, J.J.; Owusu, D., , as cited in 98CLI/WEN. [all data]

DePuy, Kass, et al., 1988
DePuy, C.H.; Kass, S.R.; Bean, G.P., Formation and Reactions of Heteroaromatic Anions in the Gas Phase, J. Org. Chem., 1988, 53, 19, 4427, https://doi.org/10.1021/jo00254a001 . [all data]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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