2-Butenal

• Formula: C₄H₆O
• Molecular weight: 70.0898
• IUPAC Standard InChI: InChI=1S/C4H6O/c1-2-3-4-5/h2-4H,1H3 Copy

  
• IUPAC Standard InChIKey: MLUCVPSAIODCQM-UHFFFAOYSA-N Copy
• CAS Registry Number: 4170-30-3
• 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.
• Stereoisomers:
  • 2-Butenal, (E)-
  • 2-Butenal, (Z)-
• Other names: Crotonaldehyde; Crotonal; Crotonic aldehyde; Crotylaldehyde; β-Methylacrolein; Propylene aldehyde; Krotonaldehyd; Rcra waste number U053; UN 1143; But-2-enal; 1-Formylpropene; 2-Butenaldehyde; NSC 56354
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Mass spectrum (electron ionization), 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

Data compiled as indicated in comments:
B - John E. Bartmess
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 C₄H₆O⁺ (ion structure unspecified)

Ionization energy determinations

De-protonation reactions

C₄H₅O^- +  =

By formula: C₄H₅O^- + H⁺ = C₄H₆O

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

References

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

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

Van-chin-syan, Kochubei, et al., 1996
Van-chin-syan, Yu.Ya.; Kochubei, V.V.; Sergeev, V.V.; Raevskii, Yu.A.; Gerasimchuk, S.I.; Kotovich, Kh.Z., Thermodynamic properties of some acids and aldehydes of the acrylic series, Sov. J. Chem. Phys. (Engl. Transl.), 1996, 70, 1789-1794, In original 1932. [all data]

Tjebbes, 1960
Tjebbes, J., Heats of combustion of butannal and some related compounds, Acta Chem. Scand., 1960, 14, 180-188. [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]

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]

Masclet and Mouvier, 1978
Masclet, P.; Mouvier, G., Etude par spectrometrie photoelectronique d'aldehydes et de cetones ethyleniques conjugues, J. Electron Spectrosc. Relat. Phenom., 1978, 14, 77. [all data]

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

Klessinger and Gunkel, 1978
Klessinger, M.; Gunkel, E., The electronic structure of polyenes and unsaturated carbonyl compounds, Tetrahedron, 1978, 34, 3591. [all data]

Bartmess and Kiplinger, 1986
Bartmess, J.E.; Kiplinger, J.P., 'Kinetic' vs. thermodynamic acidities of enones in the gas phase, J. Org. Chem., 1986, 51, 2173. [all data]

Notes

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

• Symbols used in this document:
  

  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  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
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.