Benzoxazole
- Formula: C7H5NO
- Molecular weight: 119.1207
- IUPAC Standard InChI: InChI=1S/C7H5NO/c1-2-4-7-6(3-1)8-5-9-7/h1-5H
- IUPAC Standard InChIKey: BCMCBBGGLRIHSE-UHFFFAOYSA-N
- CAS Registry Number: 273-53-0
- 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. - Other names: 1-Oxa-3-aza-1H-indene; 1-Oxa-3-azaindene; USAF ek-5017
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Condensed phase thermochemistry data
Go To: Top, Phase change 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 | -5.78 ± 0.25 | kcal/mol | Ccb | Steele, Chirico, et al., 1992 | DSC; ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -823.37 ± 0.24 | kcal/mol | Ccb | Steele, Chirico, et al., 1992 | DSC; ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°solid,1 bar | 35.600 | cal/mol*K | N/A | Steele, Chirico, et al., 1992, 2 | crystaline, I phase; S(liq,298.15 K) = 203.91 J/mol*K. S value for the liquid at 298.15 K was calculated with graphically extrapolated data.; DH |
Constant pressure heat capacity of solid
| Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 33.841 | 298.15 | Steele, Chirico, et al., 1992, 2 | crystaline, I phase; T = 5 to 650 K. Cp(liq,298.15 K) = 178.50 J/mol*K. Cp value for the liquid at 298.15 K was calculated with graphically extrapolated data.; DH |
Phase change data
Go To: Top, 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 as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Tboil | 455.7 | K | N/A | Weast and Grasselli, 1989 | BS |
| Tboil | 456. | K | N/A | American Tokyo Kasei, 1988 | BS |
| Tboil | 456. | K | N/A | Buckingham and Donaghy, 1982 | BS |
| Quantity | Value | Units | Method | Reference | Comment |
| Tfus | 304. | K | N/A | Buckingham and Donaghy, 1982 | BS |
| Quantity | Value | Units | Method | Reference | Comment |
| Ttriple | 302.500 | K | N/A | Steele, Chirico, et al., 1992, 2 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.003 K; TRC |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔsubH° | 16.6 ± 0.1 | kcal/mol | C | Sabbah and Hevia, 1998 | AC |
Enthalpy of vaporization
| ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 12.2 | 320. | EB | Steele, Chirico, et al., 1992, 2 | AC |
| 11.6 | 360. | EB | Steele, Chirico, et al., 1992, 2 | AC |
| 11.0 | 400. | EB | Steele, Chirico, et al., 1992, 2 | AC |
| 10.4 | 440. | EB | Steele, Chirico, et al., 1992, 2 | AC |
| 9.73 | 480. | EB | Steele, Chirico, et al., 1992, 2 | AC |
Enthalpy of fusion
| ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 4.011 | 302.5 | Domalski and Hearing, 1996 | AC |
Enthalpy of phase transition
| ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
|---|---|---|---|---|---|
| 0.004372 | 247.0 | crystaline, II | crystaline, I | Steele, Chirico, et al., 1992, 2 | DH |
| 4.0115 | 302.505 | crystaline, I | liquid | Steele, Chirico, et al., 1992, 2 | DH |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Steele, Chirico, et al., 1992
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.,
The thermodynamic properties of benzothiazole and benzoxazole,
J. Chem. Thermodyn., 1992, 24, 449-529. [all data]
Steele, Chirico, et al., 1992, 2
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.,
The thermodynamic properties of benzothiazole and benzoxazole,
J. Chem. Thermodynam., 1992, 24, 499-529. [all data]
Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]
American Tokyo Kasei, 1988
American Tokyo Kasei,
TCI American Organic Chemical 88/89 Catalog, American Tokyo Kasei, Portland, OR, 1988, 1610. [all data]
Buckingham and Donaghy, 1982
Buckingham, J.; Donaghy, S.M.,
Dictionary of Organic Compounds: Fifth Edition, Chapman and Hall, New York, 1982, 1. [all data]
Sabbah and Hevia, 1998
Sabbah, R.; Hevia, R.,
Energetique des liaisons intermoleculaires dans les molecules de benzoxazole et de benzothiazole,
Thermochim. Acta, 1998, 313, 131-136. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid S°solid,1 bar Entropy of solid at standard conditions (1 bar) Tboil Boiling point Tfus Fusion (melting) point Ttriple Triple point temperature ΔHtrs Enthalpy of phase transition ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔfusH Enthalpy of fusion ΔsubH° Enthalpy of sublimation at standard conditions ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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