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:
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Vibrational and/or electronic energy levels
  • Gas Chromatography
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Reaction thermochemistry data

Go To: Top, Gas phase ion energetics data, References, Notes

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

Data compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₄H₅O⁺ +  = (C₄H₅O⁺ • )

By formula: C₄H₅O⁺ + C₄H₄O = (C₄H₅O⁺ • C₄H₄O)

Bond type: Hydrogen bonds of the type OH-O between organics

Free energy of reaction

C₄H₃O^- +  =

By formula: C₄H₃O^- + H⁺ = C₄H₄O

 + 2 =

By formula: C₄H₄O + 2H₂ = C₄H₈O

C₄H₄O⁺ +  = (C₄H₄O⁺ • )

By formula: C₄H₄O⁺ + C₄H₄O = (C₄H₄O⁺ • C₄H₄O)

(C₄H₄O⁺ • ) +  = (C₄H₄O⁺ • 2)

By formula: (C₄H₄O⁺ • C₄H₄O) + C₄H₄O = (C₄H₄O⁺ • 2C₄H₄O)

 +  = ( • )

By formula: Na⁺ + C₄H₄O = (Na⁺ • C₄H₄O)

Free energy of reaction

Gas phase ion energetics data

Go To: Top, Reaction thermochemistry data, References, Notes

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

References

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Notes

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

Hiraoka, Takimoto, et al., 1987
Hiraoka, K.; Takimoto, H.; Yamabe, S., Stabilities and Structures in Cluster Ions of Five-Membered Heterocyclic Compounds Containing O, N and S Atoms, J. Am. Chem. Soc., 1987, 109, 24, 7346, https://doi.org/10.1021/ja00258a018 . [all data]

Meot-Ner (Mautner), Ross, et al., 1985
Meot-Ner (Mautner), M.; Ross, M.M.; Campana, J.E., Stable Hydrogen - Bonded Isomers of Covalent Ions, J. Am. Chem. Soc., 1985, 107, 4835. [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]

Dolliver, Gresham, et al., 1938
Dolliver, M.A.; Gresham, T.L.; Kistiakowsky, G.B.; Smith, E.A.; Vaughan, W.E., Heats of organic reactions. VI. Heats of hydrogenation of some oxygen-containing compounds, J. Am. Chem. Soc., 1938, 60, 440-450. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

McMahon and Ohanessian, 2000
McMahon, T.B.; Ohanessian, G., An Experimental and Ab Initio Study of the Nature of the Binding in Gas-Phase Complexes of Sodium Ions, Chem. Eur. J., 2000, 6, 16, 2931, https://doi.org/10.1002/1521-3765(20000818)6:16<2931::AID-CHEM2931>3.0.CO;2-7 . [all data]

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]

Notes

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

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

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