Pyridine, 2-methyl-

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δfgas-26.5kJ/molN/AKosorotov, Zemlyakova, et al., 1978Value computed using ΔfHliquid° value of -69.0 kj/mol from Kosorotov, Zemlyakova, et al., 1978 and ΔvapH° value of 42.5 kj/mol from Scott, Hubbard, et al., 1963.; DRB
Δfgas98.95 ± 0.88kJ/molCcbScott, Hubbard, et al., 1963ALS
Δfgas101.9 ± 1.3kJ/molCmAndon, Cox, et al., 1957ALS
Δfgas102.0 ± 1.3kJ/molCcbCox, Challoner, et al., 1954ALS
Δfgas87.7kJ/molN/AConstam and White, 1903Value computed using ΔfHliquid° value of 45.3 kj/mol from Constam and White, 1903 and ΔvapH° value of 42.5 kj/mol from Scott, Hubbard, et al., 1963.; DRB

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

Quantity Value Units Method Reference Comment
Δfliquid-68.99kJ/molCcbKosorotov, Zemlyakova, et al., 1978impure compound; ALS
Δfliquid56.48 ± 0.75kJ/molCcbScott, Hubbard, et al., 1963ALS
Δfliquid59.0 ± 1.3kJ/molCcbCox, Challoner, et al., 1954ALS
Δfliquid45.27kJ/molCcbConstam and White, 1903ALS
Quantity Value Units Method Reference Comment
Δcliquid-3292.4kJ/molCcbKosorotov, Zemlyakova, et al., 1978impure compound; ALS
Δcliquid-3418.0 ± 0.67kJ/molCcbScott, Hubbard, et al., 1963ALS
Δcliquid-3420.5 ± 1.3kJ/molCcbCox, Challoner, et al., 1954ALS
Δcliquid-3415.kJ/molCcbConstam and White, 1903ALS
Quantity Value Units Method Reference Comment
liquid217.86J/mol*KN/AScott, Hubbard, et al., 1963DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
158.41298.15Scott, Hubbard, et al., 1963T = 12 to 370 K.; DH

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

Quantity Value Units Method Reference Comment
Tboil402. ± 1.KAVGN/AAverage of 34 out of 35 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus206. ± 3.KAVGN/AAverage of 12 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple206.46KN/AScott, Hubbard, et al., 1963, 2Uncertainty assigned by TRC = 0.05 K; by extrapolation of 1/f to 0.0; TRC
Ttriple206.44KN/AHelm, Lanum, et al., 1958Uncertainty assigned by TRC = 0.03 K; measured in calorimeter at USBM, Bartlesville, OK; TRC
Quantity Value Units Method Reference Comment
Tc621.KN/AMajer and Svoboda, 1985 
Tc621.1KN/AKobe and Mathews, 1970Uncertainty assigned by TRC = 1. K; TRC
Quantity Value Units Method Reference Comment
Pc46.00barN/AKobe and Mathews, 1970Uncertainty assigned by TRC = 0.6079 bar; TRC
Quantity Value Units Method Reference Comment
ρc2.99mol/lN/AKobe and Mathews, 1970Uncertainty assigned by TRC = 0.32 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap42.8 ± 0.7kJ/molAVGN/AAverage of 8 values; Individual data points

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
36.17402.6N/AMajer and Svoboda, 1985 
41.2 ± 0.1320.EBChirico, Knipmeyer, et al., 1999Based on data from 308. to 441. K.; AC
38.8 ± 0.1360.EBChirico, Knipmeyer, et al., 1999Based on data from 308. to 441. K.; AC
36.4 ± 0.1400.EBChirico, Knipmeyer, et al., 1999Based on data from 308. to 441. K.; AC
33.7 ± 0.3440.EBChirico, Knipmeyer, et al., 1999Based on data from 308. to 441. K.; AC
42.0307.EBLencka, 1990Based on data from 292. to 403. K.; AC
46.9230.AStephenson and Malanowski, 1987Based on data from 209. to 245. K.; AC
36.5444.AStephenson and Malanowski, 1987Based on data from 429. to 537. K.; AC
35.4536.AStephenson and Malanowski, 1987Based on data from 521. to 621. K.; AC
39.1367.EB,IPStephenson and Malanowski, 1987Based on data from 352. to 445. K. See also Osborn and Douslin, 1968.; AC
39.1367.EBStephenson and Malanowski, 1987Based on data from 352. to 442. K. See also Rysselberghe and Fristrom, 1945.; AC
41.6 ± 0.1313.CMajer, Svoboda, et al., 1984AC
40.7 ± 0.1328.CMajer, Svoboda, et al., 1984AC
39.8 ± 0.1343.CMajer, Svoboda, et al., 1984AC
38.3 ± 0.1368.CMajer, Svoboda, et al., 1984AC
39.8352.MGHerington and Martin, 1953Based on data from 337. to 403. K.; AC
38.8 ± 0.1359.CRysselberghe and Fristrom, 1945AC
37.7 ± 0.1379.CRysselberghe and Fristrom, 1945AC
36.2 ± 0.1402.CRysselberghe and Fristrom, 1945AC

Enthalpy of vaporization

ΔvapH = A exp(-βTr) (1 − Tr)β
    ΔvapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    Tr = reduced temperature (T / Tc)

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Temperature (K) A (kJ/mol) β Tc (K) Reference Comment
298. to 403.58.880.2879621.Majer and Svoboda, 1985 

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
352.94 to 441.514.136131401.681-63.162Scott, Hubbard, et al., 1963Coefficents calculated by NIST from author's data.

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
9.7240206.45Scott, Hubbard, et al., 1963DH
9.72206.5Domalski and Hearing, 1996AC

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
47.10206.45Scott, Hubbard, et al., 1963DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


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
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
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- + Hydrogen cation = Pyridine, 2-methyl-

By formula: C6H6N- + H+ = C6H7N

Quantity Value Units Method Reference Comment
Δr1577. ± 13.kJ/molG+TSDePuy, Kass, et al., 1988gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B
Quantity Value Units Method Reference Comment
Δr1548. ± 13.kJ/molIMRBDePuy, Kass, et al., 1988gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B

C6H8N+ + Pyridine, 2-methyl- = (C6H8N+ • Pyridine, 2-methyl-)

By formula: C6H8N+ + C6H7N = (C6H8N+ • C6H7N)

Quantity Value Units Method Reference Comment
Δr96.2kJ/molPHPMSMeot-Ner M. and Sieck, 1983gas phase; M
Quantity Value Units Method Reference Comment
Δr116.J/mol*KPHPMSMeot-Ner M. and Sieck, 1983gas phase; M

Lithium ion (1+) + Pyridine, 2-methyl- = (Lithium ion (1+) • Pyridine, 2-methyl-)

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

Quantity Value Units Method Reference Comment
Δr194. ± 6.7kJ/molCIDTRodgers, 2001RCD

Sodium ion (1+) + Pyridine, 2-methyl- = (Sodium ion (1+) • Pyridine, 2-methyl-)

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

Quantity Value Units Method Reference Comment
Δr128. ± 4.6kJ/molCIDTRodgers, 2001RCD

Potassium ion (1+) + Pyridine, 2-methyl- = (Potassium ion (1+) • Pyridine, 2-methyl-)

By formula: K+ + C6H7N = (K+ • C6H7N)

Quantity Value Units Method Reference Comment
Δr98. ± 3.kJ/molCIDTRodgers, 2001RCD

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Ion clustering 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

View reactions leading to C6H7N+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)949.1kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity917.3kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.37 ± 0.05EIZaretskii, Oren, et al., 1976LLK
9.4 ± 0.1EIStefanovic and Grutzmacher, 1974LLK
9.02 ± 0.03PIWatanabe, Nakayama, et al., 1962RDSH
9.26PEKimura, Katsumata, et al., 1981Vertical value; LLK
9.18PEKlasinc, Novak, et al., 1978Vertical value; LLK
9.20PERamsey and Walker, 1974Vertical value; LLK
9.20 ± 0.05PEHeilbronner, Hornung, et al., 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C5H6+12.87 ± 0.05HCNEIZaretskii, Oren, et al., 1976LLK
C6H6N+12.4 ± 0.1HEIPalmer and Lossing, 1963RDSH

De-protonation reactions

C6H6N- + Hydrogen cation = Pyridine, 2-methyl-

By formula: C6H6N- + H+ = C6H7N

Quantity Value Units Method Reference Comment
Δr1577. ± 13.kJ/molG+TSDePuy, Kass, et al., 1988gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B
Quantity Value Units Method Reference Comment
Δr1548. ± 13.kJ/molIMRBDePuy, Kass, et al., 1988gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction 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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - 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

C6H8N+ + Pyridine, 2-methyl- = (C6H8N+ • Pyridine, 2-methyl-)

By formula: C6H8N+ + C6H7N = (C6H8N+ • C6H7N)

Quantity Value Units Method Reference Comment
Δr96.2kJ/molPHPMSMeot-Ner M. and Sieck, 1983gas phase; M
Quantity Value Units Method Reference Comment
Δr116.J/mol*KPHPMSMeot-Ner M. and Sieck, 1983gas phase; M

Potassium ion (1+) + Pyridine, 2-methyl- = (Potassium ion (1+) • Pyridine, 2-methyl-)

By formula: K+ + C6H7N = (K+ • C6H7N)

Quantity Value Units Method Reference Comment
Δr98. ± 3.kJ/molCIDTRodgers, 2001RCD

Lithium ion (1+) + Pyridine, 2-methyl- = (Lithium ion (1+) • Pyridine, 2-methyl-)

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

Quantity Value Units Method Reference Comment
Δr194. ± 6.7kJ/molCIDTRodgers, 2001RCD

Sodium ion (1+) + Pyridine, 2-methyl- = (Sodium ion (1+) • Pyridine, 2-methyl-)

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

Quantity Value Units Method Reference Comment
Δr128. ± 4.6kJ/molCIDTRodgers, 2001RCD

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, Notes

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

Kosorotov, Zemlyakova, et al., 1978
Kosorotov, V.I.; Zemlyakova, Z.F.; Platonov, V.A.; Ovchinnikov, V.G.; Simulin, Yu.N.; Dzhagatspanyan, R.V., Determination of thermal effects of the synthesis of chloropicolines and chloroaminopicolines, J. Appl. Chem. USSR (Engl. Transl.), 1978, 51, 2262-2263, In original 2376. [all data]

Scott, Hubbard, et al., 1963
Scott, D.W.; Hubbard, W.N.; Messerly, J.F.; Todd, S.S.; Hossenlopp, I.A.; Good, W.D.; Douslin, D.R.; McCullough, J.P., Chemical thermodynamic properties and internal rotation of methylpyridines. I. 2-methylpyridine, J. Phys. Chem., 1963, 67, 680-685. [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, Hubbard, et al., 1963, 2
Scott, D.W.; Hubbard, W.N.; Messerly, J.F.; Todd, S.S.; Hossenlopp, I.A.; Good, W.D.; Douslin, D.R.; McCullough, J.P., Chemical Thermodynamic Properties and Internal Rotation of Methylpyridines I. 2-Methylpyridine, J. Phys. Chem., 1963, 67, 680. [all data]

Helm, Lanum, et al., 1958
Helm, R.V.; Lanum, W.J.; Cook, G.L.; Ball, J.S., Purification and Properties of Pyrrole, Pyrrolidine, Pyridine and 2-Methylpyridine, J. Phys. Chem., 1958, 62, 858. [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]

Kobe and Mathews, 1970
Kobe, K.A.; Mathews, J.F., Critical Properties and Vapor Pressures of Some Organic Nitrogen and Oxygen Compounds, J. Chem. Eng. Data, 1970, 15, 182. [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]

Lencka, 1990
Lencka, Malgorzata, Measurements of the vapour pressures of pyridine, 2-methylpyridine, 2,4-dimethylpyridine, 2,6-dimethylpyridine, and 2,4,6-trimethylpyridine from 0.1 kPa to atmospheric pressure using a modified Swietoslawski ebulliometer, The Journal of Chemical Thermodynamics, 1990, 22, 5, 473-480, https://doi.org/10.1016/0021-9614(90)90139-H . [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]

Rysselberghe and Fristrom, 1945
Rysselberghe, Pierre Van; Fristrom, Robert M., The Conductance of Non-aqueous Solutions of Magnesium and Calcium Perchlorates 1, J. Am. Chem. Soc., 1945, 67, 4, 680-682, https://doi.org/10.1021/ja01220a053 . [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]

Meot-Ner M. and Sieck, 1983
Meot-Ner M.; Sieck, L.W., The Ionic Hydrogen Bond. 1. Sterically Hindered Bonds. Solvation and Clustering of Sterically Hindered Amines and Pyridines, J. Am. Chem. Soc., 1983, 105, 10, 2956, https://doi.org/10.1021/ja00348a005 . [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]

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]

Ramsey and Walker, 1974
Ramsey, B.G.; Walker, F.A., A linear relationship between substituted pyridine lone pair vertical ionization potentials and pKa, J. Am. Chem. Soc., 1974, 96, 3314. [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]

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

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, References