Thiophene, 2-methyl-

• Formula: C₅H₆S
• Molecular weight: 98.166
• IUPAC Standard InChI: InChI=1S/C5H6S/c1-5-3-2-4-6-5/h2-4H,1H3 Copy

  
• IUPAC Standard InChIKey: XQQBUAPQHNYYRS-UHFFFAOYSA-N Copy
• CAS Registry Number: 554-14-3
• 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.
• Other names: 2-Methylthiophene; 2-Methylthiacyclopentadiene; 2-methylthiacyclopentadiene (2-methylthiophene)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

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

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, References, Notes

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

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Constant pressure heat capacity of solid

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, References, Notes

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

Ionization energy determinations

De-protonation reactions

C₅H₅S^- +  =

By formula: C₅H₅S^- + H⁺ = C₅H₆S

References

Go To: Top, Gas phase thermochemistry data, Condensed phase 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.

Pennington, Finke, et al., 1956
Pennington, R.E.; Finke, H.L.; Hubbard, W.N.; Messerly, J.F.; Frow, F.R.; Hossenlopp, I.A.; Waddington, G., The chemical thermodynamic properties of 2-methylthiophene, J. Am. Chem. Soc., 1956, 78, 2055-2060. [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]

Carlson and Westrum, 1968
Carlson, H.G.; Westrum, E.F., Jr., Thermal study of the glass-type transformation of 2-methylthiophene, J. Chem. Eng. Data, 1968, 13, 273-274. [all data]

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]

Aloisi and Pignataro, 1973
Aloisi, G.G.; Pignataro, S., Molecular complexes of substituted thiophens with σ and π acceptors, J. Chem. Soc. Faraday Trans. 1, 1973, 69, 534. [all data]

Linda, Marino, et al., 1971
Linda, P.; Marino, G.; Pignataro, S., A comparison of sensitivities to substituent effects of five- membered heteroaromatic rings in gas phase ionization, J. Chem. Soc. B, 1971, 1585. [all data]

Baker, Betteridge, et al., 1970
Baker, A.D.; Betteridge, D.; Kemp, N.R.; Kirby, R.E., Application of photoelectron spectrometry to pesticide analysis. Photoelectron spectra of fivemembered heterocycles and related molecules, Anal. Chem., 1970, 42, 1064. [all data]

Colonna, Distefano, et al., 1979
Colonna, F.P.; Distefano, G.; Guerra, M.; Jones, D.; Modelli, A., Furyl- and thienyl-mercury derivatives studied by means of ultraviolet photoelectron spectroscopy. Evidence for the participation in bonding of the vacant 6p π orbitals of mercury in bis-2-furyl-bis-2-thienylmercury, J. Chem. Soc. Dalton Trans., 1979, 2037. [all data]

DePuy, Kass, et al., 1988
DePuy, C.H.; Kass, S.R.; Bean, G.P., Formation and Reactions of Heteroaromatic Anions in the Gas Phase, J. Org. Chem., 1988, 53, 19, 4427, https://doi.org/10.1021/jo00254a001 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  Cp,solid	Constant pressure heat capacity of solid
  S°liquid	Entropy of liquid at standard conditions
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  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
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.