Isocrotonic acid

• Formula: C₄H₆O₂
• Molecular weight: 86.0892
• IUPAC Standard InChI: InChI=1S/C4H6O2/c1-2-3-4(5)6/h2-3H,1H3,(H,5,6)/b3-2- Copy

  
• IUPAC Standard InChIKey: LDHQCZJRKDOVOX-IHWYPQMZSA-N Copy
• CAS Registry Number: 503-64-0
• 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.
• Species with the same structure:
  • 2-Butenoic acid, isomer # 1
• Stereoisomers:
  • 2-Butenoic acid, (E)-
  • Crotonic acid
• Other names: 2-Butenoic acid, (Z)-; Crotonic acid, (Z)-; (Z)-Crotonic acid; (Z)-2-Butenoic acid; cis-Crotonic Acid; cis-2-Butenoic Acid; (Z)-CH3CH=CHCOOH; (2Z)-2-Butenoic acid
• Information on this page:
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
• Options:
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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 compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

De-protonation reactions

C₄H₅O₂^- +  =

By formula: C₄H₅O₂^- + H⁺ = C₄H₆O₂

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.

Holmes, Terlouw, et al., 1979
Holmes, J.L.; Terlouw, J.K.; Vijfhuizen, P.C.; A'Campo, C., Metastable ion studies XII-Molecular and fragment ion structures for isomeric C₄H₆O₂ acids, Org. Mass Spectrom., 1979, 14, 204. [all data]

Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P., Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria, Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092 . [all data]

Graul, Schnute, et al., 1990
Graul, S.T.; Schnute, M.E.; Squires, R.R., Gas-Phase Acidities of Carboxylic Acids and Alcohols from Collision-Induced Dissociation of Dimer Cluster Ions, Int. J. Mass Spectrom. Ion Proc., 1990, 96, 2, 181, https://doi.org/10.1016/0168-1176(90)87028-F . [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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