Leucine
- Formula: C6H13NO2
- Molecular weight: 131.1729
- IUPAC Standard InChI: InChI=1S/C6H13NO2/c1-4(2)3-5(7)6(8)9/h4-5H,3,7H2,1-2H3,(H,8,9)/t5-/m1/s1
- IUPAC Standard InChIKey: ROHFNLRQFUQHCH-RXMQYKEDSA-N
- CAS Registry Number: 61-90-5
- Chemical structure:
This structure is also available as a 2d Mol file - Stereoisomers:
- Other names: L-Leucine; Leucine, L-; L-α-Aminoisocaproic acid; α-Amino-γ-methylvaleric acid; (S)-(+)-Leucine; L-(+)-Leucine; Leu; Pentanoic acid, 2-amino-4-methyl-, (S)-; 2-Amino-4-methylpentanoic acid, (L)-; 2-Amino-4-methylvaleric acid, (L)-; iso-C4H9CH(NH2)COOH; L-(-)-2-Amino-4-methylpentanoic acid; Norvaline, 4-methyl-, (L)-; Valeric acid, 2-amino-4-methyl-, (S)-; Leucin; (S)-2-Amino-4-methylpentanoic acid; (S)-Leucine; (S)-2-Amino-4-methylvaleric acid; L-Norvaline, 4-methyl-; NSC 46709
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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:
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
Enthalpy of sublimation
| ΔsubH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 35.5 ± 1.6 | 401. to 517. | TGA | Lähde, Raula, et al., 2009 | AC |
| 36.0 ± 0.2 | 455. | V | Svec and Clyde, 1965 | ALS |
| 36.0 ± 0.2 | 455. | ME | Svec and Clyde, 1965, 2 | Based on data from 446. to 464. K. See also Cox and Pilcher, 1970 and Clyde and Svec, 1964.; AC |
Enthalpy of phase transition
| ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
|---|---|---|---|---|---|
| 0.0478 | 352. | crystaline, II | crystaline, I | Grunenberg, Bougeard, et al., 1984 | DH |
Entropy of phase transition
| ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
|---|---|---|---|---|---|
| 0.14 | 352. | crystaline, II | crystaline, I | Grunenberg, Bougeard, et al., 1984 | DH |
References
Go To: Top, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Lähde, Raula, et al., 2009
Lähde, Anna; Raula, Janne; Malm, Jari; Kauppinen, Esko I.; Karppinen, Maarit,
Sublimation and vapour pressure estimation of l-leucine using thermogravimetric analysis,
Thermochimica Acta, 2009, 482, 1-2, 17-20, https://doi.org/10.1016/j.tca.2008.10.009
. [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]
Svec and Clyde, 1965, 2
Svec, H.J.; Clyde, D.D.,
Vapor Pressures of Some α-Amino Acids.,
J. Chem. Eng. Data, 1965, 10, 2, 151-152, https://doi.org/10.1021/je60025a024
. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press Inc., London, 1970, 643. [all data]
Clyde and Svec, 1964
Clyde, D.D.; Svec, H.,
, U. S. Atomic Energy Comm. IS-790, 1964, 1. [all data]
Grunenberg, Bougeard, et al., 1984
Grunenberg, A.; Bougeard, D.; Schrader, B.,
DSC-investigations of 22 crystalline neutral aliphatic amino acids in the temperature range 233 to 423 K,
Thermochim. Acta, 1984, 77, 59-66. [all data]
Notes
Go To: Top, Phase change data, References
- Symbols used in this document:
ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔsubH Enthalpy of sublimation - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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