2-Aminopyridine
- Formula: C5H6N2
- Molecular weight: 94.1145
- IUPAC Standard InChIKey: ICSNLGPSRYBMBD-UHFFFAOYSA-N
- CAS Registry Number: 504-29-0
- 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-Pyridinamine; Pyridine, 2-amino-; α-Aminopyridine; α-Pyridinamine; α-Pyridylamine; β-Pyridylamine; o-Aminopyridine; 2-Pyridylamine; Amino-2 pyridine; 1,2-Dihydro-2-iminopyridine; NSC 431
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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 118.1 ± 1.1 | kJ/mol | Ccb | Bickerton, Pilcher, et al., 1984 |
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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°solid | 39.4 ± 0.8 | kJ/mol | Ccb | Bickerton, Pilcher, et al., 1984 | |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -2864.4 ± 0.5 | kJ/mol | Ccb | Bickerton, Pilcher, et al., 1984 |
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.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 480.2 | K | N/A | Aldrich Chemical Company Inc., 1990 | BS |
Tboil | 477. | K | N/A | Buckingham and Donaghy, 1982 | BS |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 330.6 | K | N/A | Buckingham and Donaghy, 1982 | BS |
Tfus | 329.15 | K | N/A | Waclawek and Hurwic, 1967 | Uncertainty assigned by TRC = 1.5 K; TRC |
Tfus | 331.65 | K | N/A | Cumper, Ginman, et al., 1963 | Uncertainty assigned by TRC = 0.2 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 76.5 ± 0.4 | kJ/mol | C | Sabbah and da Silva Eusébio, 1998 | AC |
ΔsubH° | 78.7 ± 0.8 | kJ/mol | C | Bickerton, Pilcher, et al., 1984 | ALS |
ΔsubH° | 78.7 | kJ/mol | N/A | Bickerton, Pilcher, et al., 1984 | DRB |
ΔsubH° | 78.7 ± 0.8 | kJ/mol | C | Bickerton, Pilcher, et al., 1984 | AC |
Reduced pressure boiling point
Tboil (K) | Pressure (bar) | Reference | Comment |
---|---|---|---|
377. to 379. | 0.027 | Buckingham and Donaghy, 1982 | BS |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
15.3 | 331.5 | Sabbah and da Silva Eusébio, 1998 | AC |
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
C5H5N2- + =
By formula: C5H5N2- + H+ = C5H6N2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1519. ± 10. | kJ/mol | TDEq | Meot-ner and Kafafi, 1988 | gas phase; anchored to 88MEO scale, not the "87 acidity scale". The Kiefer, Zhang, et al., 1997 BDE is for ortho.; B |
ΔrH° | 1518. ± 8.8 | kJ/mol | G+TS | Taft and Bordwell, 1988 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1489. ± 8.4 | kJ/mol | TDEq | Meot-ner and Kafafi, 1988 | gas phase; anchored to 88MEO scale, not the "87 acidity scale". The Kiefer, Zhang, et al., 1997 BDE is for ortho.; B |
ΔrG° | 1488. ± 8.4 | kJ/mol | IMRE | Taft and Bordwell, 1988 | gas phase; B |
By formula: Li+ + C5H6N2 = (Li+ • C5H6N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 238. ± 21. | kJ/mol | CIDT | Rodgers, 2001 | RCD |
By formula: Na+ + C5H6N2 = (Na+ • C5H6N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 146. ± 5.9 | kJ/mol | CIDT | Rodgers, 2001 | RCD |
By formula: K+ + C5H6N2 = (K+ • C5H6N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 103. ± 4. | kJ/mol | CIDT | Rodgers, 2001 | RCD |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Bickerton, Pilcher, et al., 1984
Bickerton, J.; Pilcher, G.; Al-Takhin, G.,
Enthalpies of combustion of the three aminopyridines and the three cyanopyridines,
J. Chem. Thermodyn., 1984, 16, 373-378. [all data]
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]
Buckingham and Donaghy, 1982
Buckingham, J.; Donaghy, S.M.,
Dictionary of Organic Compounds: Fifth Edition, Chapman and Hall, New York, 1982, 1. [all data]
Waclawek and Hurwic, 1967
Waclawek, Z.; Hurwic, J.,
Dipole moment and spectroscopic studies of the 1,3,5-trinitrobenzene complexes with some pyridine derivatives in nonpolar solvents,
Rocz. Chem., 1967, 41, 1993. [all data]
Cumper, Ginman, et al., 1963
Cumper, C.W.N.; Ginman, R.F.A.; Redford, D.G.; Vogel, A.I.,
Physical Properties and Chemical Constitution. Part XXXVIII. The Electric Dipole Moments of Aminopyridines and Aminoquinolines.,
J. Chem. Soc., 1963, 1963, 1731. [all data]
Sabbah and da Silva Eusébio, 1998
Sabbah, Raphaël; da Silva Eusébio, Maria Ermelinda,
Energétique des liaisons inter- et intramoléculaires dans les trois isomères de l'aminopyridine,
Revue canadienne de chimie, 1998, 76, 1, 18-24, https://doi.org/10.1139/cjc-76-1-18
. [all data]
Meot-ner and Kafafi, 1988
Meot-ner, M.; Kafafi, S.A.,
Carbon Acidities of Aromatic Compounds,
J. Am. Chem. Soc., 1988, 110, 19, 6297, https://doi.org/10.1021/ja00227a003
. [all data]
Kiefer, Zhang, et al., 1997
Kiefer, J.H.; Zhang, Q.; Kern, R.D.; Yao, J.; Jursic, B.,
Pyrolysis of Aromatic Azines: Pyrazine, Pyrimidine, and Pyridine,
J. Phys. Chem. A, 1997, 101, 38, 7061, https://doi.org/10.1021/jp970211z
. [all data]
Taft and Bordwell, 1988
Taft, R.W.; Bordwell, F.G.,
Structural and Solvent Effects Evaluated from Acidities Measured in Dimethyl Sulfoxide and in the Gas Phase,
Acc. Chem. Res., 1988, 21, 12, 463, https://doi.org/10.1021/ar00156a005
. [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 Aminopyridines,
J. Phys. Chem. A, 2001, 105, 35, 8145, https://doi.org/10.1021/jp011555z
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References
- Symbols used in this document:
Tboil Boiling point Tfus Fusion (melting) point ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔfusH Enthalpy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔsubH° Enthalpy of sublimation at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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