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Dewar benzene, hexamethyl-


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
Deltafliquid-90.4kJ/molCcbSchafer and Hellmann, 1967 
Quantity Value Units Method Reference Comment
Deltacliquid-7385. ± 4.6kJ/molCcbSchafer and Hellmann, 1967Corresponding «DELTA»fliquid = 92. kJ/mol (simple calculation by NIST; no Washburn corrections)

Phase change 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: Robert L. Brown and Stephen E. Stein

Reduced pressure boiling point

Tboil (K) Pressure (bar) Reference
333.20.027Aldrich Chemical Company Inc., 1990

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 by: 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

Dewar benzene, hexamethyl- = Benzene, hexamethyl-

By formula: C12H18 = C12H18

Quantity Value Units Method Reference Comment
Deltar-235. ± 3.kJ/molCmAdam and Chang, 1969liquid phase; solvent: Pure phase
Deltar-249.kJ/molEqkOth, 1968liquid phase; Heat of isomerization, see Oth, 1969

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

By formula: C12H18 = C12H18

Quantity Value Units Method Reference Comment
Deltar-233. ± 3.kJ/molCmAdam and Chang, 1969liquid phase; solvent: Pure phase; Heat of isomerization

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:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C12H18+ (ion structure unspecified)

Ionization energy determinations

IE (eV) Method Reference Comment
7.83PEBougeard, Schrader, et al., 1974Vertical value; LLK
7.92PEMarschner, Juds, et al., 1973Vertical value; LLK

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 D.HENNEBERG, MAX-PLANCK INSTITUTE, MULHEIM, WEST GERMANY
NIST MS number 61751

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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, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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UVVis spectrum
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Source (editor), 1973
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. 18974
Instrument SF-16
Boiling point 43.0-45.0/ 15 mm

References

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

Schafer and Hellmann, 1967
Schafer, W.; Hellmann, H., Hexamethyl-Dewar-Benzol (Hexamethyl-bicyclo[2.2.0]hexa-2,5-dien), Angew. Chem., 1967, 79, 566-573. [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]

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]

Bougeard, Schrader, et al., 1974
Bougeard, D.; Schrader, B.; Bleckmann, P.; Plesser, T., Ramanspektroskopie und molekulstruktur. VII. Infrarot-, raman- und photoelektronenspektrum des hexamethyl-dewarbenzols; normalkoordinatenberechnung und untersuchung der «pi»-elektronen-wechselwirkung, Justus Liebigs Ann. Chem., 1974, 156, 137. [all data]

Marschner, Juds, et al., 1973
Marschner, F.; Juds, H.; Goetz, H., Zur homokonjugation im hexamethyl-dewar-benzol, Tetrahedron Lett., 1973, 3983. [all data]

(editor), 1973
(editor), Koptyug V.A., Atlas of Spectra of Aromatic and Heterocyclic Compounds, 1973, 3, 75. [all data]


Notes

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