Isoxazole

• Formula: C₃H₃NO
• Molecular weight: 69.0620
• IUPAC Standard InChI: InChI=1S/C3H3NO/c1-2-4-5-3-1/h1-3H Copy

  
• IUPAC Standard InChIKey: CTAPFRYPJLPFDF-UHFFFAOYSA-N Copy
• CAS Registry Number: 288-14-2
• 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: 1-Oxa-2-azacyclopentadiene; Isooxazole
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Gas phase thermochemistry 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 compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard

Ionization energy determinations

Appearance energy determinations

References

Go To: Top, Gas phase 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.

Steele, Chirico, et al., 1996
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Smith, N.K.; Tasker, I.R., Thermodynamic properties and ideal-gas enthalpies of formation for cyclohexene, phthalan (2,5-dihydrobenzo-3,4-furan), isoxazole, octylamine, dioctylamine, trioctylamine, phenyl isocyanate, and 1,4,5,6-tetrahydropyrimidine, J. Chem. Eng. Data, 1996, 41, 1269-1284. [all data]

McCormick and Hamilton, 1978
McCormick, D.G.; Hamilton, W.S., The enthalpies of combustion and formation of oxazole and isoxazole, J. Chem. Thermodyn., 1978, 10, 275-278. [all data]

McCormick, 1977
McCormick, D.G., The resonance energies of oxazole and isoxazole determined from the enthalpies of combustion and formation (Order No. 7801771), Diss. Abstr. Int. B, 1977, 38, 4271. [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]

Bouchoux and Hoppilliard, 1981
Bouchoux, G.; Hoppilliard, Y., Fragmentation mechanisms of isoxazole, Org. Mass Spectrom., 1981, 16, 459. [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]

Daamen, Oskam, et al., 1979
Daamen, H.; Oskam, A.; Stufkens, D.J.; Waaijers, H.W., Bonding properties of group VIB metal pentacarbonyl azole complexes studied by electronic absorption, photoelectron, ¹³C NMR and vibrational spectroscopy, Inorg. Chim. Acta, 1979, 34, 253. [all data]

Buschek, Holmes, et al., 1986
Buschek, J.M.; Holmes, J.L.; Lossing, F.P., The mass spectrometric generation of neutral ethynamine HC≡CNH₂ and C₂H₃N isomers., Org. Mass Spectrom., 1986, 21, 729. [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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