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

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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
Δfgas34.3kcal/molChydRoth, Adamczak, et al., 1991 

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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
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)

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Tfus274.05KN/AMurphy and Duggan, 1949Uncertainty assigned by TRC = 2. K; TRC
Quantity Value Units Method Reference Comment
Δvap10.56kcal/molVDay and Oestreich, 1957ALS

Reduced pressure boiling point

Tboil (K) Pressure (atm) Reference Comment
349.70.066Aldrich Chemical Company Inc., 1990BS
332. - 333.0.033Frinton Laboratories Inc., 1986BS

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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:
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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), 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:
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

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), References, Notes

Data compiled by: Coblentz Society, Inc.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

Mass spectrum
For Zoom
1.) Enter the desired X axis range (e.g., 100, 200)
2.) Check here for automatic Y scaling
3.) Press here to zoom

Additional Data

View image of digitized spectrum (can be printed in landscape orientation).

Due to licensing restrictions, this spectrum cannot be downloaded.

Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center, 1994
NIST MS number 135249

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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]

Murphy and Duggan, 1949
Murphy, M.T.; Duggan, A.C., Pyrolysis of Butadiene, J. Am. Chem. Soc., 1949, 71, 3347. [all data]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Frinton Laboratories Inc., 1986
Frinton Laboratories Inc., Catalog Number 11, Frinton Laboratories Inc., Vineland, NJ, 1986, 99. [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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), References