Pyridine, 2-methyl-
- Formula: C6H7N
- Molecular weight: 93.1265
- IUPAC Standard InChIKey: BSKHPKMHTQYZBB-UHFFFAOYSA-N
- CAS Registry Number: 109-06-8
- 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-Picoline; α-Methylpyridine; α-Picoline; o-Picoline; 2-Methylpyridine; Picoline, α; Rcra waste number U191; o-Methylpyridine; NSC 3409
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -26.5 | kJ/mol | N/A | Kosorotov, Zemlyakova, et al., 1978 | Value 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 |
ΔfH°gas | 98.95 ± 0.88 | kJ/mol | Ccb | Scott, Hubbard, et al., 1963 | ALS |
ΔfH°gas | 101.9 ± 1.3 | kJ/mol | Cm | Andon, Cox, et al., 1957 | ALS |
ΔfH°gas | 102.0 ± 1.3 | kJ/mol | Ccb | Cox, Challoner, et al., 1954 | ALS |
ΔfH°gas | 87.7 | kJ/mol | N/A | Constam and White, 1903 | Value 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
Go To: Top, Gas phase thermochemistry 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:
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 |
---|---|---|---|---|---|
ΔfH°liquid | -68.99 | kJ/mol | Ccb | Kosorotov, Zemlyakova, et al., 1978 | impure compound; ALS |
ΔfH°liquid | 56.48 ± 0.75 | kJ/mol | Ccb | Scott, Hubbard, et al., 1963 | ALS |
ΔfH°liquid | 59.0 ± 1.3 | kJ/mol | Ccb | Cox, Challoner, et al., 1954 | ALS |
ΔfH°liquid | 45.27 | kJ/mol | Ccb | Constam and White, 1903 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -3292.4 | kJ/mol | Ccb | Kosorotov, Zemlyakova, et al., 1978 | impure compound; ALS |
ΔcH°liquid | -3418.0 ± 0.67 | kJ/mol | Ccb | Scott, Hubbard, et al., 1963 | ALS |
ΔcH°liquid | -3420.5 ± 1.3 | kJ/mol | Ccb | Cox, Challoner, et al., 1954 | ALS |
ΔcH°liquid | -3415. | kJ/mol | Ccb | Constam and White, 1903 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 217.86 | J/mol*K | N/A | Scott, Hubbard, et al., 1963 | DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
158.41 | 298.15 | Scott, Hubbard, et al., 1963 | T = 12 to 370 K.; DH |
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- + =
By formula: C6H6N- + H+ = C6H7N
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1577. ± 13. | kJ/mol | G+TS | DePuy, Kass, et al., 1988 | gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1548. ± 13. | kJ/mol | IMRB | DePuy, Kass, et al., 1988 | gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B |
By formula: C6H8N+ + C6H7N = (C6H8N+ • C6H7N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 96.2 | kJ/mol | PHPMS | Meot-Ner M. and Sieck, 1983 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 116. | J/mol*K | PHPMS | Meot-Ner M. and Sieck, 1983 | gas phase; M |
By formula: Li+ + C6H7N = (Li+ • C6H7N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 194. ± 6.7 | kJ/mol | CIDT | Rodgers, 2001 | RCD |
By formula: Na+ + C6H7N = (Na+ • C6H7N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 128. ± 4.6 | kJ/mol | CIDT | Rodgers, 2001 | RCD |
By formula: K+ + C6H7N = (K+ • C6H7N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 98. ± 3. | kJ/mol | CIDT | Rodgers, 2001 | RCD |
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:
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) | 949.1 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 917.3 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.37 ± 0.05 | EI | Zaretskii, Oren, et al., 1976 | LLK |
9.4 ± 0.1 | EI | Stefanovic and Grutzmacher, 1974 | LLK |
9.02 ± 0.03 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
9.26 | PE | Kimura, Katsumata, et al., 1981 | Vertical value; LLK |
9.18 | PE | Klasinc, Novak, et al., 1978 | Vertical value; LLK |
9.20 | PE | Ramsey and Walker, 1974 | Vertical value; LLK |
9.20 ± 0.05 | PE | Heilbronner, Hornung, et al., 1972 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C5H6+ | 12.87 ± 0.05 | HCN | EI | Zaretskii, Oren, et al., 1976 | LLK |
C6H6N+ | 12.4 ± 0.1 | H | EI | Palmer and Lossing, 1963 | RDSH |
De-protonation reactions
C6H6N- + =
By formula: C6H6N- + H+ = C6H7N
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1577. ± 13. | kJ/mol | G+TS | DePuy, Kass, et al., 1988 | gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1548. ± 13. | kJ/mol | IMRB | DePuy, Kass, et al., 1988 | gas phase; Acid: 2-methylpyridine. Between EtOH, iPrOH; B |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction 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.
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]
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, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy Cp,liquid Constant pressure heat capacity of liquid 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 ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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