Isoprene
- Formula: C5H8
- Molecular weight: 68.1170
- IUPAC Standard InChIKey: RRHGJUQNOFWUDK-UHFFFAOYSA-N
- CAS Registry Number: 78-79-5
- 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: 1,3-Butadiene, 2-methyl-; β-Methylbivinyl; Isopentadiene; 2-Methyl-1,3-butadiene; 2-Methylbutadiene; CH2=C(CH3)CH=CH2; 2-Methylbuta-1,3-diene; 3-Methyl-1,3-butadiene; NSC 9237
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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
RCD - Robert C. Dunbar
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Individual Reactions
C5H7- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1613. ± 21. | kJ/mol | G+TS | Bartmess and McIver Jr., 1979 | gas phase; Between H2O, MeOH. Acid: isoprene; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1586. ± 21. | kJ/mol | IMRB | Bartmess and McIver Jr., 1979 | gas phase; Between H2O, MeOH. Acid: isoprene; B |
By formula: C11H8N4 = C6N4 + C5H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 157. ± 3. | kJ/mol | Cm | Rogers, 1971 | solid phase; Heat of formation derived by 77PED/RYL; ALS |
By formula: C6N4 + C5H8 = C11H8N4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -157. ± 3. | kJ/mol | Cm | Rogers, 1971 | liquid phase; solvent: Dichloromethane; ALS |
By formula: Ag+ + C5H8 = (Ag+ • C5H8)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 164. ± 19. | kJ/mol | RAK | Ho, Yang, et al., 1997 | RCD |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Bartmess and McIver Jr., 1979
Bartmess, J.E.; McIver Jr.,
The Gas Phase Acidity Scale
in Gas Phase Ion Chemistry, Gas Phase Ion Chemistry, V. 2, M.T. Bowers, Ed., Academic Press, NY, 1979, Ch. 11, Elsevier, 1979. [all data]
Rogers, 1971
Rogers, F.E.,
Thermochemistry of the Diels-Alder reaction. I. Enthalpy of addition of isoprene to tetracyanoethylene,
J. Phys. Chem., 1971, 75, 1734-1737. [all data]
Ho, Yang, et al., 1997
Ho, Y.-P.; Yang, Y.-C.; Klippenstein, S.J.; Dunbar, R.C.,
Binding Energies of Ag+ and Cd+ Complexes from Analysis of Radiative Association Kinetics,
J. Phys. Chem. A, 1997, 101, 18, 3338, https://doi.org/10.1021/jp9637284
. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
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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