Alanine

• Formula: C₃H₇NO₂
• Molecular weight: 89.0932
• IUPAC Standard InChI: InChI=1S/C3H7NO2/c1-2(4)3(5)6/h2H,4H2,1H3,(H,5,6)/t2-/m1/s1 Copy

  
• IUPAC Standard InChIKey: QNAYBMKLOCPYGJ-UWTATZPHSA-N Copy
• CAS Registry Number: 56-41-7
• 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.
• Stereoisomers:
  • dl-Alanine
  • D-Alanine
  • 2-aminopropanoic acid
• Other names: L-Alanine; Alanine, L-; α-Alanine; α-Aminopropionic acid; (S)-Alanine; L-α-Alanine; L-α-Aminopropionic acid; L-(+)-Alanine; L-2-Aminopropanoic acid; L-2-Aminopropionic acid; Propanoic acid, 2-amino-; Propanoic acid, 2-amino-, (S)-; L-CH3CH(NH2)COOH; (S)-2-Aminopropanoic acid; 2-Aminopropanoic acid; 2-Aminopropionic acid; Ala; Ritalanine; NSC 206315; 2-Aminopropanoic acid, L-
• 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
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
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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

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 solid

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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of sublimation

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

C₃H₆NO₂^- +  =

By formula: C₃H₆NO₂^- + H⁺ = C₃H₇NO₂

 +  = ( • )

By formula: Na⁺ + C₃H₇NO₂ = (Na⁺ • C₃H₇NO₂)

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
MM - Michael M. Meot-Ner (Mautner)
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

De-protonation reactions

C₃H₆NO₂^- +  =

By formula: C₃H₆NO₂^- + H⁺ = C₃H₇NO₂

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: Na⁺ + C₃H₇NO₂ = (Na⁺ • C₃H₇NO₂)

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

UV/Visible spectrum

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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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

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, Mass spectrum (electron ionization), UV/Visible spectrum, Notes

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

Ngauv, Sabbah, et al., 1977
Ngauv, S.N.; Sabbah, R.; Laffitte, M., Thermodynamique de composes azotes. III. Etude thermochimique de la glycine et de la l-α-alanine, Thermochim. Acta, 1977, 20, 371-380. [all data]

Contineanu and Marchidan, 1984
Contineanu, I.; Marchidan, D.I., The enthalpies of combustion and formation of D-alanine, L-alanine, DL-alanine, and β-alanine, Rev. Roum. Chim., 1984, 29, 43-48. [all data]

Hutchens, Cole, et al., 1963
Hutchens, J.O.; Cole, A.G.; Stout, J.W., Heat capacities from 11 to 305°K., entropies, and free energies of formation of L-valine, L-isoleucine, and L-leucine, J. Phys. Chem., 1963, 67, 1128-1130. [all data]

Tsuzuki, Harper, et al., 1958
Tsuzuki, T.; Harper, D.O.; Hunt, H., Heats of combustion. VII. The heats of combustion of some amino acids, J. Phys. Chem., 1958, 62, 1594-1595. [all data]

Lemoult, 1904
Lemoult, M.P., Remarques sur une serie recenie de determinations calorimetriques, Compt. Rend., 1904, 663-635. [all data]

Hutchens, Cole, et al., 1960
Hutchens, J.O.; Cole, A.G.; Stout, J.W., Heat capacities from 11 to 305K. and entropies of L-alanine and glycine, J. Am. Chem. Soc., 1960, 82, 4813-4815. [all data]

Daurel, Delhaes, et al., 1975
Daurel, M.; Delhaes, P.; Dupart, E., Variations thermiques, entre 1 et 300K, de la chaleur specifique de la L-alanine, tri(L-alanine) et de la poly(L-alanine), Biopolymers, 1975, 14, 801-823. [all data]

Badelin, Kulikov, et al., 1990
Badelin, V.G.; Kulikov, O.V.; Batagin, V.S.; Udzig, E.; Zielenkiewicz, A.; Zielenkiewicz, W.; Krestov, G.A., Physico-chemical properties of peptides and their solutions, Thermochim. Acta, 1990, 169, 81-93. [all data]

Kulikov, Kozlov, et al., 1989
Kulikov, O.V.; Kozlov, V.A.; Malenkina, L.I.; Badelin, V.G., Heat capacities of amino acids and peptides and excess characteristics ot their aqueous solutions, Sbornik Nauch. Trud., Termodin. Rast. neelect., Ivanovo, Inst. nevod. rast., 1989, Akad. [all data]

Nguon Ngauv, Sabbah, et al., 1977
Nguon Ngauv, Song; Sabbah, Raphael; Laffitie, Marc, Thermodynamique de composes azotes III. Etude Thermochimique de la glycine et de la l-α-alanine, Thermochimica Acta, 1977, 20, 3, 371-380, https://doi.org/10.1016/0040-6031(77)85091-0 . [all data]

de Kruif, Voogd, et al., 1979
de Kruif, C.G.; Voogd, J.; Offringa, J.C.A., Enthalpies of sublimation and vapour pressures of 14 amino acids and peptides, The Journal of Chemical Thermodynamics, 1979, 11, 7, 651-656, https://doi.org/10.1016/0021-9614(79)90030-2 . [all data]

Svec and Clyde, 1965
Svec, H.J.; Clyde, D.D., Vapor pressures of some α-amino acids, J. Chem. Eng. Data, 1965, 10, 151. [all data]

Jones, Bernier, et al., 2007
Jones, C.M.; Bernier, M.; Carson, E.; Colyer, K.E.; Metz, R.; Pawlow, A.; Wischow, E.D.; Webb, I.; Andriole, E.J.; Poutsma, J.C., Gas-phase Acities of the 20 Protein Amino Acids, Int. J. Mass Spectrom., 2007, 267, 1-3, 54-62, https://doi.org/10.1016/j.ijms.2007.02.018 . [all data]

Locke and McIver, 1983
Locke, M.J.; McIver, R.T., Jr., Effect of Solvation on the Acid/Base Properties of Glycine, J. Am. Chem. Soc., 1983, 105, 4226. [all data]

Gapeev and Dunbar, 2003
Gapeev, A.; Dunbar, R.C., Na+ Affinities of Gas-Phase Amino Acids by Ligand Exchange Equilibrium, Int. J. Mass Spectrom., 2003, 228, 2-3, 825, https://doi.org/10.1016/S1387-3806(03)00242-2 . [all data]

Kish, Ohanessian, et al., 2003
Kish, M.M.; Ohanessian, G.; Wesdemiotis, C., The Na+ affinities of a-amino acids: side-chain substituent effects, Int. J. Mass Spectrom., 2003, 227, 3, 509, https://doi.org/10.1016/S1387-3806(03)00082-4 . [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]

Bouchoux and Salpin, 2003
Bouchoux, G.; Salpin, J.Y., Gas-phase basicity of glycine, alanine, proline, serine, lysine, histidine and some of their peptides by the thermokinetic method, European J. Mass Spectrometry, 2003, 9, 391-402. [all data]

Hahn and Wesdemiotis, 2003
Hahn, I.S.; Wesdemiotis, C., Protonation Thermochemistry of beta-Alanine. An Evaluation of Proton Affinities and Entropies Determined by the Extended Kinetic Method, Int. J. Mass Spectrometry, 2003, 222, 465. [all data]

Cassady, Carr, et al., 1995
Cassady, C.J.; Carr, S.R.; Zhang, K.; Chung-Phillips, C., Experimental and Ab Intio Studies of Protonations of Alanine and Samll Peptides of Alanine and Glycine, J. Org. Chem., 1995, 60, 1704. [all data]

Wu and Lebrilla, 1995
Wu, J.; Lebrilla, C.B., Intrinsic Basicity of Oligomeric Peptides that Contain Glycine, Alanine, and Valine - The Effects of the Alkyl Side Chain on Proton Transfer Reactions, J. Am. Soc. Mass Spectrom., 1995, 6, 91. [all data]

Klasinc, 1976
Klasinc, L., Application of photoelectron spectroscopy to biologically active molecules and their constituent parts, J. Electron Spectrosc. Relat. Phenom., 1976, 8, 161. [all data]

Debies and Rabalais, 1974
Debies, T.P.; Rabalais, J.W., Electronic structure of amino acids and ureas, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 315. [all data]

Slifkin and Allison, 1967
Slifkin, M.A.; Allison, A.C., Measurement of ionization potentials from contact charge transfer spectra, Nature, 1967, 215, 949. [all data]

Abu-Eittah, et al., 1988
Abu-Eittah, R., et al., Bull. Chem. Soc. Japan., 1988, 61, 2609. [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, Mass spectrum (electron ionization), UV/Visible spectrum, References

• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  IE (evaluated)	Recommended ionization energy
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  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
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

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