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

• Formula: C₈H₁₀
• Molecular weight: 106.1650
• IUPAC Standard InChI: InChI=1S/C8H10/c1-7(2)8-5-3-4-6-8/h3-6H,1-2H3 Copy

  
• IUPAC Standard InChIKey: WXACXMWYHXOSIX-UHFFFAOYSA-N Copy
• CAS Registry Number: 2175-91-9
• 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-Cyclopentadiene, 5-isopropylidene-; Dimethylfulvene; Isopropylidenecyclopentadiene; 5-Isopropylidene-1,3-cyclopentadiene; 6,6-Dimethylfulvene; 5-(1-Methylethylidene)-1,3-cyclopentadiene; 5-Isopropylidenecyclopentadiene; Fulvene, 6,6-dimethyl
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • IR Spectrum
  • Gas Chromatography
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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.

Phase change data

Go To: Top, Gas phase ion energetics data, 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

Reduced pressure boiling point

Gas phase ion energetics data

Go To: Top, Phase change data, 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

De-protonation reactions

C₈H₉^- +  =

By formula: C₈H₉^- + H⁺ = C₈H₁₀

Mass spectrum (electron ionization)

Go To: Top, Phase change data, Gas phase ion energetics 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 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.

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

References

Go To: Top, Phase change data, Gas phase ion energetics data, 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.

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

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]

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]

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]

Notes

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

• Symbols used in this document:
  

  Tboil	Boiling point
  Tfus	Fusion (melting) point
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH°	Enthalpy of vaporization at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.