MeCO2 anion

• Formula: C₂H₃O₂^-
• Molecular weight: 59.0446
• IUPAC Standard InChI: InChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4)/p-1 Copy

  
• IUPAC Standard InChIKey: QTBSBXVTEAMEQO-UHFFFAOYSA-M Copy
• CAS Registry Number: 71-50-1
• Chemical structure:
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• Information on this page:
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Ion clustering data
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Reaction thermochemistry data

Go To: Top, 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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Individual Reactions

 +  = ( • )

By formula: C₂H₃O₂^- + H₂O = (C₂H₃O₂^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • 2) +  = ( • 3)

By formula: (C₂H₃O₂^- • 2H₂O) + H₂O = (C₂H₃O₂^- • 3H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

 +  =

By formula: C₂H₃O₂^- + H⁺ = C₂H₄O₂

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • H₂O) + H₂O = (C₂H₃O₂^- • 2H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

( • 4) +  = ( • 5)

By formula: (C₂H₃O₂^- • 4CHN) + CHN = (C₂H₃O₂^- • 5CHN)

Free energy of reaction

( • 2 • ) +  = ( • 3 • )

By formula: (C₂H₃O₂^- • 2C₂H₄O₂ • H₂O) + C₂H₄O₂ = (C₂H₃O₂^- • 3C₂H₄O₂ • H₂O)

( •  • ) +  = ( • 2 • )

By formula: (C₂H₃O₂^- • C₂H₄O₂ • H₂O) + C₂H₄O₂ = (C₂H₃O₂^- • 2C₂H₄O₂ • H₂O)

 +  = ( • )

By formula: C₂H₃O₂^- + C₃H₆O = (C₂H₃O₂^- • C₃H₆O)

Bond type: Hydrogen bonds of deprotonated acids to ketones/

 +  = ( • )

By formula: C₂H₃O₂^- + C₂H₄O = (C₂H₃O₂^- • C₂H₄O)

Bond type: Hydrogen bonds of deprotonated acids to ketones/

 +  = ( • )

By formula: C₂H₃O₂^- + C₃H₇NO = (C₂H₃O₂^- • C₃H₇NO)

Bond type: Hydrogen bonds of deprotonated acids to amides

( • 2) +  = ( • 3)

By formula: (C₂H₃O₂^- • 2CHN) + CHN = (C₂H₃O₂^- • 3CHN)

( • 3) +  = ( • 4)

By formula: (C₂H₃O₂^- • 3CHN) + CHN = (C₂H₃O₂^- • 4CHN)

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • CHN) + CHN = (C₂H₃O₂^- • 2CHN)

 +  = ( • )

By formula: C₂H₃O₂^- + C₆H₆O = (C₂H₃O₂^- • C₆H₆O)

 +  = ( • )

By formula: C₂H₃O₂^- + C₆H₁₄O₃ = (C₂H₃O₂^- • C₆H₁₄O₃)

 +  = ( • )

By formula: C₂H₃O₂^- + C₂H₆O = (C₂H₃O₂^- • C₂H₆O)

 +  = ( • )

By formula: C₂H₃O₂^- + C₄H₅N = (C₂H₃O₂^- • C₄H₅N)

 +  = ( • )

By formula: C₂H₃O₂^- + C₈H₇N = (C₂H₃O₂^- • C₈H₇N)

 +  = ( • )

By formula: C₂H₃O₂^- + CH₄S = (C₂H₃O₂^- • CH₄S)

 +  = ( • )

By formula: C₂H₃O₂^- + C₂H₃N = (C₂H₃O₂^- • C₂H₃N)

( • ) +  = ( •  • )

By formula: (C₂H₃O₂^- • C₆H₁₁NO₃) + H₂O = (C₂H₃O₂^- • H₂O • C₆H₁₁NO₃)

Bond type: Hydrogen bond (negative ion to hydride)

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • C₃H₆O) + C₃H₆O = (C₂H₃O₂^- • 2C₃H₆O)

Bond type: Hydrogen bonds of deprotonated acids to ketones/

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • C₃H₇NO) + C₃H₇NO = (C₂H₃O₂^- • 2C₃H₇NO)

Bond type: Hydrogen bonds of deprotonated acids to amides

( • ) +  = ( •  • )

By formula: (C₂H₃O₂^- • H₂O) + C₂H₄O₂ = (C₂H₃O₂^- • C₂H₄O₂ • H₂O)

 +  = ( • )

By formula: C₂H₃O₂^- + CHN = (C₂H₃O₂^- • CHN)

 +  = ( • )

By formula: C₂H₃O₂^- + C₆H₁₁NO₃ = (C₂H₃O₂^- • C₆H₁₁NO₃)

 +  = ( • )

By formula: C₂H₃O₂^- + CH₄O = (C₂H₃O₂^- • CH₄O)

( • ) +  = ( •  • )

By formula: (C₂H₃O₂^- • H₂O) + C₆H₁₁NO₃ = (C₂H₃O₂^- • C₆H₁₁NO₃ • H₂O)

( • 2) +  = ( • 3)

By formula: (C₂H₃O₂^- • 2C₂H₄O₂) + C₂H₄O₂ = (C₂H₃O₂^- • 3C₂H₄O₂)

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • C₂H₄O₂) + C₂H₄O₂ = (C₂H₃O₂^- • 2C₂H₄O₂)

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • C₆H₁₁NO₃) + C₆H₁₁NO₃ = (C₂H₃O₂^- • 2C₆H₁₁NO₃)

( • ) +  = ( • 2)

By formula: (C₂H₃O₂^- • C₄H₅N) + C₄H₅N = (C₂H₃O₂^- • 2C₄H₅N)

 +  = ( • )

By formula: C₂H₃O₂^- + C₂H₄O₂ = (C₂H₃O₂^- • C₂H₄O₂)

 +  = ( • )

By formula: C₂H₃O₂^- + C₆H₁₁NO₃ = (C₂H₃O₂^- • C₆H₁₁NO₃)

 +  = ( • )

By formula: C₂H₃O₂^- + C₃H₄N₂ = (C₂H₃O₂^- • C₃H₄N₂)

( • 4294967295) +  =

By formula: (C₂H₃O₂^- • 4294967295CO₂) + CO₂ = C₂H₃O₂^-

References

Go To: Top, Reaction thermochemistry data, Notes

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

Wincel, 2008
Wincel, H., Hydration energies of deprotonated amino acids from gas phase equilibria measurements, J. Am. Soc. Mass Spectrom., 2008, 19, 8, 1091-1097, https://doi.org/10.1016/j.jasms.2008.05.014 . [all data]

Meot-ner, Elmore, et al., 1999
Meot-ner, M.; Elmore, D.E.; Scheiner, S., Ionic Hydrogen Bond Effects on the Acidities, Basicities, Solvation, Solvent Bridging and Self-assembly of Carboxylic Groups, J. Am. Chem. Soc., 1999, 121, 33, 7625, https://doi.org/10.1021/ja982173i . [all data]

Meot-Ner and Sieck, 1986
Meot-Ner, M.; Sieck, L.W., The ionic hydrogen bond and ion solvation. 5. OH...O^- bonds. Gas phase solvation and clustering of alkoxide and carboxylate anions, J. Am. Chem. Soc., 1986, 108, 7525. [all data]

Blades, Klassen, et al., 1995
Blades, A.T.; Klassen, J.S.; Kebarle, P., Free Energies of Hydration in the Gas Phase on the Anions of Some Oxo Acids of C, N, S, P, Cl and I, J. Am. Chem. Soc., 1995, 117, 42, 10563, https://doi.org/10.1021/ja00147a019 . [all data]

Meot-ner, 1988
Meot-ner, M., Ionic Hydrogen Bond and Ion Solvation. ₆. Interaction Energies of the Acetate Ion with Organic Molecules. Comparison of CH₃COO^- with Cl^-, CN^-, and SH^-, J. Am. Chem. Soc., 1988, 110, 12, 3854, https://doi.org/10.1021/ja00220a022 . [all data]

Angel and Ervin, 2006
Angel, L.A.; Ervin, K.M., Gas-phase acidities and O-H bond dissociation enthalpies of phenol, 3-methylphenol, 2,4,6-trimethylphenol, and ethanoic acid, J. Phys. Chem. A, 2006, 110, 35, 10392-10403, https://doi.org/10.1021/jp0627426 . [all data]

Taft and Topsom, 1987
Taft, R.W.; Topsom, R.D., The Nature and Analysis of Substituent Effects, Prog. Phys. Org. Chem., 1987, 16, 1. [all data]

Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P., Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A), Can. J. Chem., 1978, 56, 1. [all data]

Fujio, McIver, et al., 1981
Fujio, M.; McIver, R.T., Jr.; Taft, R.W., Effects on the acidities of phenols from specific substituent-solvent interactions. Inherent substituent parameters from gas phase acidities, J. Am. Chem. Soc., 1981, 103, 4017. [all data]

Muftakhov, Vasil'ev, et al., 1999
Muftakhov, M.V.; Vasil'ev, Y.V.; Mazunov, V.A., Determination of electron affinity of carbonyl radicals by means of negative ion mass spectrometry, Rapid Commun. Mass Spectrom., 1999, 13, 12, 1104-1108, https://doi.org/10.1002/(SICI)1097-0231(19990630)13:12<1104::AID-RCM619>3.0.CO;2-C . [all data]

Meot-ner, Cybulski, et al., 1988
Meot-ner, M.; Cybulski, S.M.; Scheiner, S.; Liebman, J.F., Is CN^- Significantly Anisotropic? Comparison of CN^- vs. Cl^-: Clustering with HCN and Condensed Phase Thermochemistry, J. Phys. Chem., 1988, 92, 10, 2738, https://doi.org/10.1021/j100321a009 . [all data]

Meot-Ner (Mautner), 1988
Meot-Ner (Mautner), M., Models for Strong Interactions in Proteins and Enzymes. 2. Interactions of Ions with the Peptide Link and Imidazole, J. Am. Chem. Soc., 1988, 110, 10, 3075, https://doi.org/10.1021/ja00218a014 . [all data]

Wenthold and Squires, 1994
Wenthold, P.G.; Squires, R.R., Gas-phase properties and reactivity of the acetate radical anion. Determination of the C-H bond strengths in acetic acid and acetate ion, J. Am. Chem. Soc., 1994, 116, 26, 11890, https://doi.org/10.1021/ja00105a032 . [all data]

Notes

Go To: Top, Reaction thermochemistry data, References

• Symbols used in this document:
  

  T	Temperature
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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