Benzene, hexamethyl-

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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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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

Hexamethyltetracyclo[2.2.0(2,6).0(3,5)]hexane = Benzene, hexamethyl-

By formula: C12H18 = C12H18

Quantity Value Units Method Reference Comment
Δr-82.5 ± 0.8kcal/molCmAdam and Chang, 1969liquid phase; solvent: Pure phase; Heat of isomerization; ALS
Δr-91.2kcal/molEqkOth, 1968liquid phase; Heat of isomerization, see Oth, 1969; ALS
Δr-91.5kcal/molCmOth, 1968liquid phase; solvent: Toluene-d8; Heat of isomerization at 150°C; ALS

Dewar benzene, hexamethyl- = Benzene, hexamethyl-

By formula: C12H18 = C12H18

Quantity Value Units Method Reference Comment
Δr-56.2 ± 0.6kcal/molCmAdam and Chang, 1969liquid phase; solvent: Pure phase; ALS
Δr-59.5kcal/molEqkOth, 1968liquid phase; Heat of isomerization, see Oth, 1969; ALS

C6H7N+ + Benzene, hexamethyl- = (C6H7N+ • Benzene, hexamethyl-)

By formula: C6H7N+ + C12H18 = (C6H7N+ • C12H18)

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Δr17.1kcal/molPHPMSMeot-Ner (Mautner) and El-Shall, 1986gas phase; M
Quantity Value Units Method Reference Comment
Δr24.3cal/mol*KPHPMSMeot-Ner (Mautner) and El-Shall, 1986gas phase; M

Anti-1,2,3,5,6-pentamethyl-4-methylenebicyclo[3.1.0]hex-2-ene = Benzene, hexamethyl-

By formula: C12H18 = C12H18

Quantity Value Units Method Reference Comment
Δr-42.7kcal/molCisoChilds and Mulholland, 1983liquid phase; ALS

Mass spectrum (electron ionization)

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

Spectrum

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Mass spectrum
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Additional Data

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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 Japan AIST/NIMC Database- Spectrum MS-NW- 223
NIST MS number 228195

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UV/Visible spectrum

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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: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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UVVis spectrum
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Source missing citation
Owner INEP CP RAS, NIST OSRD
Collection (C) 2007 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS
Source reference RAS UV No. 8969
Instrument Zeiss PMQ II
Melting point 166.5
Boiling point 263.4

References

Go To: Top, Reaction thermochemistry data, Mass spectrum (electron ionization), UV/Visible spectrum, Notes

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

Adam and Chang, 1969
Adam, W.; Chang, J.C., Kinetics and thermochemistry of valence isomerization by differential scanning calorimetry: the case of hexamethylprismane and hexamethyldewarbenzene, Int. J. Chem. Kinet., 1969, 1, 487-492. [all data]

Oth, 1968
Oth, J.F.M., The kinetics and thermochemistry of the thermal rearrangement of hexamethylbicyclo[2.2.0]hexa-2,5-diene (hexamethyldewarbenzene) and of hexamethyltetracyclo[2.2.0,0(2,6).0(3,5)]hexane (hexamethylprismane), Chem. Ber., 1968, 47, 1185-1195. [all data]

Oth, 1969
Oth, J.F.M., The kinetics and thermochemistry of the thermal rearrangement of hexamethyl(Dewar benzene) and of hexamethylprismane, Angew. Chem. Int. Ed. Engl., 1969, 7, 646. [all data]

Meot-Ner (Mautner) and El-Shall, 1986
Meot-Ner (Mautner), M.; El-Shall, M.S., Ionic Charge Transfer Complexes. 1. Cationic Complexes with Delocalized and Partially Localized pi Systems, J. Am. Chem. Soc., 1986, 108, 15, 4386, https://doi.org/10.1021/ja00275a026 . [all data]

Childs and Mulholland, 1983
Childs, R.F.; Mulholland, D.L., Thermochemical relationships between some bicyclohexenyl and benzenium cations, J. Am. Chem. Soc., 1983, 105, 96-99. [all data]


Notes

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