Pyridine, 3-methyl-

• Formula: C₆H₇N
• Molecular weight: 93.1265
• IUPAC Standard InChI: InChI=1S/C6H7N/c1-6-3-2-4-7-5-6/h2-5H,1H3 Copy

  
• IUPAC Standard InChIKey: ITQTTZVARXURQS-UHFFFAOYSA-N Copy
• CAS Registry Number: 108-99-6
• 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: 3-Picoline; β-Methylpyridine; β-Picoline; m-Picoline; 3-Methylpyridine; meta-Methylpyridine; beta-Picoline; 5-Methylpyridine; m-Methylpyridine; NSC 18251
• 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
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • References
  • Notes
• Other data available:
  • Henry's Law data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Gas 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
DRB - Donald R. Burgess, Jr.

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
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Enthalpy of vaporization

Δ_vapH = A exp(-βT_r) (1 − T_r)^β
    Δ_vapH = Enthalpy of vaporization (at saturation pressure) (kcal/mol)
    T_r = reduced temperature (T / T_c)

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Antoine Equation Parameters

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

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Enthalpy of sublimation

Enthalpy of fusion

Entropy of fusion

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 as indicated in comments:
B - John E. Bartmess
RCD - Robert C. Dunbar

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

C₆H₆N^- +  =

By formula: C₆H₆N^- + H⁺ = C₆H₇N

 +  = ( • )

By formula: Li⁺ + C₆H₇N = (Li⁺ • C₆H₇N)

 +  = ( • )

By formula: Na⁺ + C₆H₇N = (Na⁺ • C₆H₇N)

 +  = ( • )

By formula: K⁺ + C₆H₇N = (K⁺ • C₆H₇N)

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
L - 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

View reactions leading to C₆H₇N⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₆H₆N^- +  =

By formula: C₆H₆N^- + H⁺ = C₆H₇N

Ion clustering 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: Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = ( • )

By formula: K⁺ + C₆H₇N = (K⁺ • C₆H₇N)

 +  = ( • )

By formula: Li⁺ + C₆H₇N = (Li⁺ • C₆H₇N)

 +  = ( • )

By formula: Na⁺ + C₆H₇N = (Na⁺ • C₆H₇N)

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• VAPOR (0.5 MICROLITER AT 150 C); NICOLET FTIR; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 CM^-1 cm^-1 resolution

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

• gas

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Notes

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

Gerasimov, Gubareva, et al., 1992
Gerasimov, P.A.; Gubareva, A.I.; Tarbeeva, N.A.; Kunderenko, V.M., Physicochemical characteristics of β-picoline, J. Appl. Chem. USSR, 1992, 65, 388-390. [all data]

Scott, Good, et al., 1963
Scott, D.W.; Good, W.D.; Guthrie, G.B.; Todd, S.S.; Hossenlopp, I.A.; Osborn, A.G.; McCullough, J.P., Chemical thermodynamic properties and internal rotation of methylpyridines. II. 3-methylpyridine, J. Phys. Chem., 1963, 67, 685-689. [all data]

Andon, Cox, et al., 1957
Andon, R.J.L.; Cox, J.D.; Herington, E.F.G.; Martin, J.F., The second virial coefficients of pyridine and benzene, and certain of their methyl homologues, Trans. Faraday Soc., 1957, 53, 1074. [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]

Constam and White, 1903
Constam, E.J.; White, J., Physico-chemical investigations in the pyridine series, Am. Chem. J., 1903, 29, 1-49. [all data]

Scott, Good, et al., 1963, 2
Scott, D.W.; Good, W.D.; Guthrie, G.B.; Todd, S.S.; Hossenlopp, I.A.; Osborn, A.G.; McCullough, J.P., Chemical Thermodynamic Properties and Internal Rotation of Methylpyridines II. 3-Methylpyridine, J. Phys. Chem., 1963, 67, 685. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Ambrose and Grant, 1957
Ambrose, D.; Grant, D.G., The Critical Temperatures of Some Hydrocarbons and Pyridine Bases, Trans. Faraday Soc., 1957, 53, 771. [all data]

Chirico, Knipmeyer, et al., 1999
Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Steele, W.V., Thermodynamic properties of the methylpyridines. Part 2. Vapor pressures, heat capacities, critical properties, derived thermodynamic functions between the temperatures 250 K and 560 K, and equilibrium isomer distributions for all temperatures ≥250 K, The Journal of Chemical Thermodynamics, 1999, 31, 3, 339-378, https://doi.org/10.1006/jcht.1998.0451 . [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]

Osborn and Douslin, 1968
Osborn, Ann G.; Douslin, Donald R., Vapor pressure relations of 13 nitrogen compounds related to petroleum, J. Chem. Eng. Data, 1968, 13, 4, 534-537, https://doi.org/10.1021/je60039a024 . [all data]

Majer, Svoboda, et al., 1984
Majer, V.; Svoboda, V.; Lencka, M., Enthalpies of vaporization and cohesive energies of pyridine and isomeric methylpyridines, J. Chem. Thermodyn., 1984, 16, 1019-1024. [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]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [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]

Rodgers, 2001
Rodgers, M.T., Substituent Effects in the Binding of Alkali Metal Ions to Pyridines, Studied by Threshold Collision-Induced Dissociation and ab Initio Theory: The Methylpyridines, J. Phys. Chem. A, 2001, 105, 11, 2374, https://doi.org/10.1021/jp004055z . [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]

Modelli and Distefano, 1981
Modelli, A.; Distefano, G., He(I) photoelectron spectra of chloro-, vinyl- and acetyl-pyridines, J. Electron Spectrosc. Relat. Phenom., 1981, 23, 323. [all data]

Zaretskii, Oren, et al., 1976
Zaretskii, Z.V.I.; Oren, D.; Kelner, L., Automatic method for the measurement of the electron impact ionization and appearance potentials, Appl. Spectrosc., 1976, 30, 366. [all data]

Stefanovic and Grutzmacher, 1974
Stefanovic, D.; Grutzmacher, H.F., The ionisation potential of some substituted pyridines, Org. Mass Spectrom., 1974, 9, 1052. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Klasinc, Novak, et al., 1978
Klasinc, L.; Novak, I.; Scholz, M.; Kluge, G., Photoelektronenspektren substituierter Pyridine und Benzole und ihre Interpretation durch die CNDO/SWW-Methode, Croat. Chem. Acta, 1978, 51, 43. [all data]

Palmer and Lossing, 1963
Palmer, T.F.; Lossing, F.P., Free radicals by mass spectrometry. XXX. Ionization potentials of anilino and 2-, 3-, and 4-pyridylmethyl radicals, J. Am. Chem. Soc., 1963, 85, 1733. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  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
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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