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:
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Mass spectrum (electron ionization)
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

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

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Reaction 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: John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₄H₅O₂^- +  =

By formula: C₄H₅O₂^- + H⁺ = C₄H₆O₂

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, Reaction thermochemistry 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.

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]

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]

Notes

Go To: Top, Reaction thermochemistry data, 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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