Thioacetic acid

• Formula: C₂H₄OS
• Molecular weight: 76.118
• IUPAC Standard InChI: InChI=1S/C2H4OS/c1-2(3)4/h1H3,(H,3,4) Copy

  
• IUPAC Standard InChIKey: DUYAAUVXQSMXQP-UHFFFAOYSA-N Copy
• CAS Registry Number: 507-09-5
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: Methanecarbothiolic acid; Thioacetic S-acid; Ethanethioic acid; Acetyl mercaptan; Ethanethiolic acid; Thiacetic acid; Thiolacetic acid; Thionoacetic acid; CH3COSH; Kyselina thiooctova; UN 2436; USAF EK-P-737; Acetic acid, thio-
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• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Data at other public NIST sites:
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Condensed phase 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Phase change 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: William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

=  + 

By formula: C₄H₆O₂S = C₂H₂O + C₂H₄OS

 +  =  + 

By formula: C₂H₄OS + H₂O = C₂H₄O₂ + H₂S

 +  =

By formula: C₂H₄OS + C₃H₆O = C₅H₁₀O₂S

 +  =

By formula: C₂H₂O + C₂H₄OS = C₄H₆O₂S

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:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C₂H₄OS⁺ (ion structure unspecified)

Ionization energy determinations

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

Gas Chromatography

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Van Den Dool and Kratz RI, polar column, custom temperature program

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References

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, Notes

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

Sunner, 1963
Sunner, S., Corrected heat of combustion and formation values for a number of organic sulphur compounds, Acta Chem. Scand., 1963, 17, 728-730. [all data]

Sunner, 1955
Sunner, S., Thermochemical investigations on organic sulfur compounds. V. On the resonance energy of thiolacetic acid, thiourea, thiosemicarbzaide, thiophene and thianthrene, Acta Chem. Scand., 1955, 9, 847-854. [all data]

Sunner and Wadso, 1957
Sunner, S.; Wadso, I., The heat of hydrolysis of thiolacetic acid, Trans. Faraday Soc., 1957, 53, 455-459. [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]

Dykyj, Svoboda, et al., 1999
Dykyj, J.; Svoboda, J.; Wilhoit, R.C.; Frenkel, M.L.; Hall, K.R., Vapor Pressure of Chemicals: Part A. Vapor Pressure and Antoine Constants for Hydrocarbons and Sulfur, Selenium, Tellurium and Hydrogen Containing Organic Compounds, Springer, Berlin, 1999, 373. [all data]

Blake and Speis, 1974
Blake, P.G.; Speis, A., Reactions of keten. Part IV. Kinetics and thermodynamics of the gas-phase reaction: Thioacetic acid + keten = acetic Thioanhydride, J. Chem. Soc. Perkin Trans. 2, 1974, 1879-1881. [all data]

Horii, Kawamura, et al., 1972
Horii, T.; Kawamura, S.; Tsurugi, J., A NMR study of the thioacetic acid-acetone mixture, Bull. Chem. Soc. Jpn., 1972, 45, 2200-2202. [all data]

Nagata, Yamabe, et al., 1975
Nagata, S.; Yamabe, T.; Fukui, K., A study of the electronic spectra of thioacetic acid and its ethyl ester, J. Phys. Chem., 1975, 79, 2335. [all data]

Huynh-Ba, Matthey-Doret, et al., 2003
Huynh-Ba, T.; Matthey-Doret, W.; Fay, L.B.; Rhlid, R.B., Generation of thiols by biotransformation of cysteine-aldehyde conjugates with Baker's yeast, J. Agric. Food Chem., 2003, 51, 12, 3629-3635, https://doi.org/10.1021/jf026198j . [all data]

Notes

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• Symbols used in this document:
  

  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization

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