Uracil
- Formula: C4H4N2O2
- Molecular weight: 112.0868
- IUPAC Standard InChI: InChI=1S/C4H4N2O2/c7-3-1-2-5-4(8)6-3/h1-2H,(H2,5,6,7,8)
- IUPAC Standard InChIKey: ISAKRJDGNUQOIC-UHFFFAOYSA-N
- CAS Registry Number: 66-22-8
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: 2,4(1H,3H)-Pyrimidinedione; Pirod; Pyrod; RU 12709; Ura; 2,4-Dihydroxypyrimidine; 2,4-Dioxopyrimidine; 2,4-Pyrimidinediol; 2,4-Pyrimidinedione; 2,6-Dihydroxypyrimidine; Hybar X; 1H-Pyrimidine-2,4-dione; 2-Hydroxy-4(1H)-pyrimidinone; 2-Hydroxy-4(3H)-pyrimidinone; 2,4-Dioxypyrimidine; 4-Hydroxy-2(1H)-pyrimidinone; NSC 3970
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Gas phase thermochemistry 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 compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | -303.1 ± 2.3 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 |
Condensed phase thermochemistry data
Go To: Top, Gas 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 compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°solid | -424.4 ± 2.5 | kJ/mol | Ccb | Wilson, Watson, et al., 1979 | ALS |
| ΔfH°solid | -429.56 ± 0.60 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -1721.3 ± 2.2 | kJ/mol | Ccb | Wilson, Watson, et al., 1979 | ALS |
| ΔcH°solid | -1716.14 ± 0.28 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | ALS |
Constant pressure heat capacity of solid
| Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 120.5 | 298. | Kilday, 1978 | DH |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Condensed phase 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 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. 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
+
= (
•
)
By formula: Na+ + C4H4N2O2 = (Na+ • C4H4N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 135. ± 3. | kJ/mol | CIDT | Rodgers and Armentrout, 2000 | |
| ΔrH° | 141. | kJ/mol | CIDC | Cerda and Wesdemiotis, 1996 |
+
= (
•
)
By formula: K+ + C4H4N2O2 = (K+ • C4H4N2O2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 101. | kJ/mol | CIDC | Cerda and Wesdemiotis, 1996 |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Nabavian, Sabbah, et al., 1977
Nabavian, P.M.; Sabbah, R.; Chastel, R.; Laffitte, M.,
Thermodynamique de composes azotes. II. Etude thermochimique des acides aminobenzoiques, de la pyrimidine, de l'uracile et de la thymine.,
J. Chim. Phys., 1977, 74, 115-126. [all data]
Wilson, Watson, et al., 1979
Wilson, S.R.; Watson, I.D.; Malcolm, G.N.,
Enthalpies of formation of solid cytosine, L-histidine, and uracil,
J. Chem. Thermodyn., 1979, 11, 911-912. [all data]
Kilday, 1978
Kilday, M.V.,
Enthalpies of solution of the nucleic acid bases. 4. Uracil in water,
J. Res., 1978, NBS 83, 547-554. [all data]
Rodgers and Armentrout, 2000
Rodgers, M.T.; Armentrout, P.B.,
Noncovalent Interactions of Nucleic Acid Bases (Uracil, Thymine, and Adenine) with Alkali Metal Ions. Threshold Collision-Induced Dissociation and Theoretical Studies,
J. Am. Chem. Soc., 2000, 121, 35, 8548, https://doi.org/10.1021/ja001638d
. [all data]
Cerda and Wesdemiotis, 1996
Cerda, B.A.; Wesdemiotis, C.,
PAs of Peptides,
J. Am. Chem. Soc., 1996, 118, 11884. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid 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 ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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