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-
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• Information on this page:
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
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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, 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.

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, 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

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