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:
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Condensed 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Phase change 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 as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos

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, Condensed phase thermochemistry data, Phase change 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]

Steele, Chirico, et al., 1993
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Tasker, I.R., Determination of ideal gas enthalpies of formation for key compounds the 1991 project results, DIPPR Project, 1993, 871, NIPER-716. [all data]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Steele, Chirico, et al., 1996, 2
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 Dioctylamine, trioctylamine, Phenyl Isocyanate, and 1,4,5,6-Tetrahydropyrimidine, J. Chem. Eng. Data, 1996, 41, 1269-84. [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

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  Tboil	Boiling point
  Tc	Critical temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

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