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:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
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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

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

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry 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
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

References

Go To: Top, 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.

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]

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]

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]

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]

Notes

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, 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°solid	Enthalpy of formation of solid at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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