Pyridine, 2,5-dimethyl-

• Formula: C₇H₉N
• Molecular weight: 107.1531
• IUPAC Standard InChI: InChI=1S/C7H9N/c1-6-3-4-7(2)8-5-6/h3-5H,1-2H3 Copy

  
• IUPAC Standard InChIKey: XWKFPIODWVPXLX-UHFFFAOYSA-N Copy
• CAS Registry Number: 589-93-5
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: 2,5-Lutidine; 2,5-Dimethylpyridine; 5-methyl-2-methylpyridine
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• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Henry's Law data
  • UV/Visible spectrum
  • Gas Chromatography
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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 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

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 as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
DH - Eugene S. Domalski and Elizabeth D. Hearing
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Enthalpy of fusion

Temperature of phase transition

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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C₇H₉N⁺ (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

References

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

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

Cox and Gundry, 1958
Cox, J.D.; Gundry, H.A., Heats of combustion. Part II. The six lutidines, J. Chem. Soc., 1958, 1019-1022. [all data]

Cox, Challoner, et al., 1954
Cox, J.D.; Challoner, A.R.; Meetham, A.R., The heats of combustion of pyridine and certain of its derivatives, J. Chem. Soc., 1954, 265-271. [all data]

Steele, Chirico, et al., 1986
Steele, W.V.; Chirico, R.D.; Collier, W.B.; Hossenlopp, I.A.; Nguyen, A.; Strube, M.M., Thermochemical and thermophysical properties of organic nitrogen compounds found in fossil materials, NIPER Report, 1986, 188, 112p. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Jankun-Pinska, 1964
Jankun-Pinska, J., Liquid-liquid equilibrium in series of ternary systems formed by pyridine bases, benzene and water. II. ternary systems: 2,4-lutidine-benzene-water, 2,5-lutidine-benzene-water and 2,6-lutidine-b, Bull. Acad. Pol. Sci., Ser. Sci. Chim., 1964, 12, 843. [all data]

Prostakov, Gaivoronskaya, et al., 1963
Prostakov, N.S.; Gaivoronskaya, L.A.; Mikheeva, N.N.; Filippov, N.P., Substituted Pyridines: 2,5-Dimethyl-4-alkylpyridines, Zh. Obshch. Khim., 1963, 33, 2928. [all data]

Farberov, Kut'in, et al., 1961
Farberov, M.I.; Kut'in, A.M.; Ustavshchikov, V.F., The conditions of 2-methyl-5-vinylprydine synthesis, Zh. Prikl. Khim. (Leningrad), 1961, 34, 632. [all data]

Kyte, Jeffery, et al., 1960
Kyte, C.T.; Jeffery, G.H.; Vogel, A.I., Physical Properties and Chem. Constitution XXVII. Pyridine Derivatives, J. Chem. Soc., 1960, 1960, 4454. [all data]

Coulson, Cox, et al., 1959
Coulson, E.A.; Cox, J.D.; Herington, E.F.G.; Martin, J.F., The Preparation and Physical Properties of the Pure Lutidines, J. Chem. Soc., 1959, 1959, 1934. [all data]

Chirico, Hossenlopp, et al., 1994
Chirico, R.D.; Hossenlopp, I.A.; Gammon, B.E.; Knipmeyer, S.E.; Steele, W.V., Heat capacities of the six dimethylpyridines between the temperatures 10 K and 445 K and methyl-group rotational barriers in the solid state a,b, J. Chem. Thermodyn., 1994, 26, 11, 1187, https://doi.org/10.1006/jcht.1994.1138 . [all data]

Ambrose, Cox, et al., 1960
Ambrose, D.; Cox, J.D.; Townsend, R., The critical temperatures of forty organic compounds, Trans. Faraday Soc., 1960, 56, 1452. [all data]

Cox, 1960
Cox, J.D., The second virial coefficients, latent heats of vaporization and heats of formation of the lutidines, Trans. Faraday Soc., 1960, 56, 959. [all data]

Steele, Chirico, et al., 1995
Steele, W.V.; Chirico, R.D.; Nguyen, A.; Knipmeyer, S.E., Vapor pressures, high-temperature heat capacities, critical properties, derived thermodynamic functions, and barriers to methyl-group rotation, for the six dimethylpyridines, The Journal of Chemical Thermodynamics, 1995, 27, 3, 311-334, https://doi.org/10.1006/jcht.1995.0030 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Herington and Martin, 1953
Herington, E.F.G.; Martin, J.F., Vapour pressures of pyridine and its homologues, Trans. Faraday Soc., 1953, 49, 154, https://doi.org/10.1039/tf9534900154 . [all data]

Kkykj and Repas, 1973
Kkykj, J.; Repas, M., Petrochemia, 1973, 13, 179. [all data]

Herington and Martin, 1953, 2
Herington, E.F.G.; Martin, J.F., Vapour Pressures of Pyridine and its Homologues, Trans. Faraday Soc., 1953, 49, 154-162, https://doi.org/10.1039/tf9534900154 . [all data]

Chirico, Hossenlopp, et al., 1994, 2
Chirico, R.D.; Hossenlopp, I.A.; Gammon, B.E.; Knipmeyer, S.E.; Steele, W.V., Heat capacities of the six dimethylpyridines between the temperatures 10 K and 445 K and methyl-group rotational barriers in the solid state a,b, The Journal of Chemical Thermodynamics, 1994, 26, 11, 1187-1218, https://doi.org/10.1006/jcht.1994.1138 . [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]

Heilbronner, Hornung, et al., 1972
Heilbronner, E.; Hornung, V.; Pinkerton, F.H.; Thames, S.F., 31. Photoelectron spectra of azabenzenes and azanaphthalenes: III. The orbital sequence in methyl- and trimethylsilyl- substituted pyridines, Helv. Chim. Acta, 1972, 55, 289. [all data]

Notes

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

• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  Ttrs	Temperature of phase transition
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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