- Formula: C4H6
- Molecular weight: 54.0904
- IUPAC Standard InChIKey: XNMQEEKYCVKGBD-UHFFFAOYSA-N
- CAS Registry Number: 503-17-3
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
- Other names: But-2-yne; Dimethylacetylene; CH3C«equiv»CCH3; Crotonylene; UN 1144
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Reaction thermochemistry 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:
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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.
C4H5- + =
By formula: C4H5- + H+ = C4H6
|rH°||1628. ± 8.8||kJ/mol||G+TS||Gal, Decouzon, et al., 2001||gas phase; Acid: MeC«equiv»CMe; B|
|rH°||1628. ± 14.||kJ/mol||G+TS||N/A||gas phase; Measured vs pyridine; B|
|rG°||1597. ± 8.4||kJ/mol||IMRE||Gal, Decouzon, et al., 2001||gas phase; Acid: MeC«equiv»CMe; B|
|rG°||1596. ± 13.||kJ/mol||IMRE||N/A||gas phase; Measured vs pyridine; B|
2 + =
By formula: 2H2 + C4H6 = C4H10
|rH°||-272.4 ± 1.3||kJ/mol||Chyd||Conn, Kistiakowsky, et al., 1939||gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -274.4 ± 0.54 kJ/mol; At 355 K; ALS|
Go To: Top, Reaction thermochemistry data, Notes
Gal, Decouzon, et al., 2001
Gal, J.F.; Decouzon, M.; Maria, P.C.; Gonzalez, A.I.; Mo, O.; Yanez, M.; El Chaouch, S.; Guillemin, J.C., Acidity trends in alpha,beta-unsaturated alkanes, silanes, germanes, and stannanes, J. Am. Chem. Soc., 2001, 123, 26, 6353-6359, https://doi.org/10.1021/ja004079j . [all data]
Conn, Kistiakowsky, et al., 1939
Conn, J.B.; Kistiakowsky, G.B.; Smith, E.A., Heats of organic reactions. VIII. Some further hydrogenations, including those of some acetylenes, J. Am. Chem. Soc., 1939, 61, 1868-1876. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
rG° Free energy of reaction at standard conditions rH° Enthalpy of reaction at standard conditions
- Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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