1,3-Cyclopentadiene, 5-(1-methylethylidene)-

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Gas phase 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δfgas34.3kcal/molChydRoth, Adamczak, et al., 1991 

Condensed phase 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δcliquid-1115.5 ± 1.2kcal/molCcbDay and Oestreich, 1957Reanalyzed by Cox and Pilcher, 1970, Original value = -1114.5 kcal/mol; Corresponding Δfliquid = 21.52 kcal/mol (simple calculation by NIST; no Washburn corrections)

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.

Individual Reactions

C8H9- + Hydrogen cation = 1,3-Cyclopentadiene, 5-(1-methylethylidene)-

By formula: C8H9- + H+ = C8H10

Quantity Value Units Method Reference Comment
Δr354.1 ± 3.2kcal/molG+TSBrickhouse and Squires, 1988gas phase; Acidity between nPrSH, iPrSH; B
Quantity Value Units Method Reference Comment
Δr347.5 ± 3.0kcal/molIMRBBrickhouse and Squires, 1988gas phase; Acidity between nPrSH, iPrSH; B

3Hydrogen + 1,3-Cyclopentadiene, 5-(1-methylethylidene)- = Cyclopentane, (1-methylethyl)-

By formula: 3H2 + C8H10 = C8H16

Quantity Value Units Method Reference Comment
Δr-72.2 ± 0.1kcal/molChydRoth, Adamczak, et al., 1991liquid phase; ALS

Gas phase ion energetics 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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C8H10+ (ion structure unspecified)

Ionization energy determinations

IE (eV) Method Reference Comment
8.03PEHouk, George, et al., 1974Vertical value; LLK

De-protonation reactions

C8H9- + Hydrogen cation = 1,3-Cyclopentadiene, 5-(1-methylethylidene)-

By formula: C8H9- + H+ = C8H10

Quantity Value Units Method Reference Comment
Δr354.1 ± 3.2kcal/molG+TSBrickhouse and Squires, 1988gas phase; Acidity between nPrSH, iPrSH; B
Quantity Value Units Method Reference Comment
Δr347.5 ± 3.0kcal/molIMRBBrickhouse and Squires, 1988gas phase; Acidity between nPrSH, iPrSH; B

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Roth, Adamczak, et al., 1991
Roth, W.R.; Adamczak, O.; Breuckmann, R.; Lennartz, H.-W.; Boese, R., Die Berechnung von Resonanzenergien; das MM2ERW-Kraftfeld, Chem. Ber., 1991, 124, 2499-2521. [all data]

Day and Oestreich, 1957
Day, J.H.; Oestreich, C., Fulvenes: III. Heat of combustion and resonance energy, J. Org. Chem., 1957, 22, 214-216. [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]

Brickhouse and Squires, 1988
Brickhouse, M.D.; Squires, R.R., Gas Phase Bronsted vs. Lewis Acid-Base Reactions of 6,6-Dimethylfulvene. A Sensitive Probe of the Electronic Structures of Organic Anions, J. Am. Chem. Soc., 1988, 110, 9, 2706, https://doi.org/10.1021/ja00217a002 . [all data]

Houk, George, et al., 1974
Houk, K.N.; George, J.K.; Duke, R.E., Jr., A frontier molecular orbital treatment of fulvene cycloadditions. Molecular orbital calculations and photoelectron spectra of substituted fulvenes, Tetrahedron, 1974, 30, 523. [all data]


Notes

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