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
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas Chromatography
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
  • 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

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

UV/Visible spectrum

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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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, 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]

Johnson and Sheridan, 1967
Johnson, E.A.; Sheridan, J., UV atlas of organic compounds, 1967, 3, G3/2. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, 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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