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
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• Information on this page:
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
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  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
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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

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

References

Go To: Top, 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.

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 ion energetics data, References

• Symbols used in this document:
  

  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
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