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:
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Phase change data

Go To: Top, 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
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of sublimation

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

References

Go To: Top, Phase change 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.

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]

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]

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]

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]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  IE (evaluated)	Recommended ionization energy
  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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