1,3-Cyclohexadiene
- Formula: C6H8
- Molecular weight: 80.1277
- IUPAC Standard InChIKey: MGNZXYYWBUKAII-UHFFFAOYSA-N
- CAS Registry Number: 592-57-4
- 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: Cyclohexa-1,3-diene; 1,2-Dihydrobenzene
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Gas phase ion energetics data
Go To: Top, Mass spectrum (electron ionization), Gas Chromatography, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
View reactions leading to C6H8+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 837. | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 804.5 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.25 | PE | Kimura, Katsumata, et al., 1981 | LLK |
8.25 ± 0.02 | PE | Bieri, Burger, et al., 1977 | LLK |
8.25 ± 0.03 | PI | Demeo and El-Sayed, 1970 | RDSH |
8.25 | PE | Bischof and Heilbronner, 1970 | RDSH |
8.28 ± 0.05 | EI | Franklin and Carroll, 1969 | RDSH |
8.32 | PE | Worley, Webb, et al., 1979 | Vertical value; LLK |
8.25 ± 0.03 | PE | Heilbronner, Hoshi, et al., 1976 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C3H2+ | 23.51 ± 0.50 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C3H3+ | 14.87 ± 0.10 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C3H4+ | 14.52 ± 0.10 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C4H2+ | 19.81 ± 0.10 | C2H2+2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H3+ | 17.62 ± 0.10 | C2H2+H2+H? | EI | Franklin and Carroll, 1969 | RDSH |
C4H4+ | 13.91 ± 0.20 | C2H2+H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H5+ | 14.69 ± 0.10 | C2H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C4H6+ | 12.60 ± 0.10 | C2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C5H3+ | 15.44 ± 0.10 | CH3+H2? | EI | Franklin and Carroll, 1969 | RDSH |
C5H5+ | 13.02 ± 0.10 | CH3 | EI | Franklin and Carroll, 1969 | RDSH |
C6H5+ | 13.92 ± 0.10 | H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 10.12 ± 0.10 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 9.88 ± 0.10 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C6H7+ | 10.45 | H | PIPECO | Lias and Ausloos, 1985 | LBLHLM |
C6H7+ | 10.82 ± 0.10 | H | EI | Franklin and Carroll, 1969 | RDSH |
De-protonation reactions
C6H7- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1561. ± 17. | kJ/mol | G+TS | Lee and Squires, 1986 | gas phase; Between SiH4, tBuOH; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1531. ± 17. | kJ/mol | IMRB | Lee and Squires, 1986 | gas phase; Between SiH4, tBuOH; value altered from reference due to change in acidity scale; B |
Mass spectrum (electron ionization)
Go To: Top, Gas phase ion energetics data, Gas Chromatography, 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
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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 | NIST Mass Spectrometry Data Center, 1990. |
NIST MS number | 118700 |
Gas Chromatography
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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Packed | C78, Branched paraffin | 130. | 689.6 | Dallos, Sisak, et al., 2000 | He; Column length: 3.3 m |
Packed | C78, Branched paraffin | 130. | 688.6 | Reddy, Dutoit, et al., 1992 | Chromosorb G HP; Column length: 3.3 m |
Packed | Squalane | 70. | 655. | Safina, Poznyak, et al., 1989 | He, Risorb (0.2-0.3 mm); Column length: 2. m |
Capillary | OV-1 | 100. | 673.1 | Engewald, Billing, et al., 1987 | Column length: 50. m; Column diameter: 0.3 mm |
Capillary | SE-30 | 130. | 684. | Bredael, 1982 | Column length: 100. m; Column diameter: 0.5 mm |
Capillary | SE-30 | 80. | 671. | Bredael, 1982 | Column length: 100. m; Column diameter: 0.5 mm |
Capillary | Apiezon L | 100. | 693. | Morishita, Okano, et al., 1980 | Column length: 45. m; Column diameter: 0.25 mm |
Capillary | Squalane | 50. | 652.8 | Bajus, Veselý, et al., 1979 | Column length: 100. m; Column diameter: 0.25 mm |
Capillary | Squalane | 70. | 653.4 | Bajus, Veselý, et al., 1979 | Column length: 100. m; Column diameter: 0.25 mm |
Packed | Squalane | 27. | 649. | Bogoslovsky, Anvaer, et al., 1978 | |
Packed | Squalane | 49. | 654. | Bogoslovsky, Anvaer, et al., 1978 | |
Packed | Squalane | 67. | 659. | Bogoslovsky, Anvaer, et al., 1978 | |
Packed | Squalane | 70. | 655. | Bogoslovsky, Anvaer, et al., 1978 | |
Packed | Squalane | 86. | 663. | Bogoslovsky, Anvaer, et al., 1978 | |
Capillary | Squalane | 42.5 | 652. | Engewald, Epsch, et al., 1974 | N2; Column length: 100. m; Column diameter: 0.23 mm |
Capillary | Squalane | 70. | 655. | Engewald, Epsch, et al., 1974 | N2; Column length: 100. m; Column diameter: 0.23 mm |
Packed | SE-30 | 75. | 688. | Robinson and Odell, 1971 | N2, Chromosorb W; Column length: 6.1 m |
Packed | Squalane | 100. | 662. | Robinson and Odell, 1971 | N2, Embacel; Column length: 3.0 m |
Packed | Squalane | 27. | 649. | Hively and Hinton, 1968 | He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm |
Packed | Squalane | 49. | 655. | Hively and Hinton, 1968 | He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm |
Packed | Squalane | 67. | 659. | Hively and Hinton, 1968 | He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm |
Packed | Squalane | 86. | 664. | Hively and Hinton, 1968 | He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm |
Capillary | Squalane | 70. | 655. | Schomburg, 1966 |
Kovats' RI, polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Capillary | PEG-20M | 100. | 883. | Morishita, Okano, et al., 1980 | Column length: 75. m; Column diameter: 0.25 mm |
Kovats' RI, polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | DB-Wax | 849. | Umano and Shibamoto, 1987 | He, 40. C @ 10. min, 2. K/min; Column length: 60. m; Column diameter: 0.25 mm; Tend: 200. C |
Van Den Dool and Kratz RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Petrocol DH | 653. | White, Hackett, et al., 1992 | 100. m/0.25 mm/0.5 μm, He, 1. K/min; Tstart: 30. C; Tend: 220. C |
Packed | SE-30 | 665. | Buchman, Cao, et al., 1984 | He, Chromosorb AW, 40. C @ 10. min, 10. K/min, 210. C @ 30. min; Column length: 3.05 m |
Van Den Dool and Kratz RI, non-polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Packed | SE-30 | 665. | Peng, Ding, et al., 1988 | Supelcoport; Chromosorb; Column length: 3.05 m; Program: 40C(5min) => 10C/min => 200C or 250C (60min) |
Van Den Dool and Kratz RI, polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Packed | Carbowax 20M | 861. | Buchman, Cao, et al., 1984 | He, Supelcoport, 40. C @ 10. min, 10. K/min, 210. C @ 30. min; Column length: 3.05 m |
Normal alkane RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Capillary | Squalane | 70. | 655. | Schomburg, 1966, 2 |
Normal alkane RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Petrocol DH | 657. | Supelco, 2012 | 100. m/0.25 mm/0.50 μm, Helium, 20. C @ 15. min, 15. K/min, 220. C @ 30. min |
Capillary | PONA | 634. | Zhang, Ding, et al., 2009 | 50. m/0.20 mm/0.50 μm, Nitrogen, 35. C @ 15. min, 2. K/min, 200. C @ 10. min |
Capillary | OV-101 | 634. | Orav, Kailas, et al., 1999 | 50. m/0.20 mm/0.50 μm, Helium, 30. C @ 6. min, 1. K/min; Tend: 100. C |
Normal alkane RI, non-polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Squalane | 671. | Chen, 2008 | Program: not specified |
Capillary | OV-101 | 664. | Zenkevich, 1998 | He; Column length: 25. m; Column diameter: 0.20 mm; Program: not specified |
Capillary | OV-101 | 665. | Zenkevich, 1998 | He; Column length: 25. m; Column diameter: 0.20 mm; Program: not specified |
Capillary | OV-1, SE-30, Methyl silicone, SP-2100, OV-101, DB-1, etc. | 671. | Waggott and Davies, 1984 | Hydrogen; Column length: 50. m; Column diameter: 0.32 mm; Program: not specified |
Packed | SE-30 | 678. | Robinson and Odell, 1971 | N2, Chromosorb W; Column length: 6.1 m; Program: 50C910min) => 20C/min => 90(6min) => 10C/min => 150C(hold) |
Packed | Squalane | 692. | Robinson and Odell, 1971 | N2, Embacel; Column length: 3.0 m; Program: 25C(5min) => 2C/min => 35 => 4C/min => 95C(hold) |
Normal alkane RI, polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | DB-Wax | 864. | Peng, Yang, et al., 1991 | Program: not specified |
References
Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G.,
Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update,
J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018
. [all data]
Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S.,
Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules
in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]
Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P.,
Valence ionization enrgies of hydrocarbons,
Helv. Chim. Acta, 1977, 60, 2213. [all data]
Demeo and El-Sayed, 1970
Demeo, D.A.; El-Sayed, M.A.,
Ionization potential and structure of olefins,
J. Chem. Phys., 1970, 52, 2622. [all data]
Bischof and Heilbronner, 1970
Bischof, P.; Heilbronner, E.,
Photoelektron-Spektren von Cycloalkenen und Cycloalkadienen,
Helv. Chim. Acta, 1970, 53, 1677. [all data]
Franklin and Carroll, 1969
Franklin, J.L.; Carroll, S.R.,
Effect of molecular structure on ionic decomposition. II. An electron-impact study of 1,3-and 1,4-cyclohexadiene and 1,3,5-hexatriene,
J. Am. Chem. Soc., 1969, 91, 6564. [all data]
Worley, Webb, et al., 1979
Worley, S.D.; Webb, T.R.; Gibson, D.H.; Ong, T.-S.,
On the electronic structures of cyclobutadiene trimethylenemethane,
J. Organomet. Chem., 1979, 168, 16. [all data]
Heilbronner, Hoshi, et al., 1976
Heilbronner, E.; Hoshi, T.; von Rosenberg, J.L.; Hafner, K.,
Alkyl-induced, natural hypsochromic shifts of the 2A←2X and 2B←2X transitions of azulene and naphthalene radical cations,
Nouv. J. Chim., 1976, 1, 105. [all data]
Lias and Ausloos, 1985
Lias, S.G.; Ausloos, P.,
Structures of C6H7+ ions formed in unimolecular and bimolecular reactions,
J. Chem. Phys., 1985, 82, 3613. [all data]
Lee and Squires, 1986
Lee, R.E.; Squires, R.R.,
Anionic homoaromaticity: A gas phase experimental study,
J. Am. Chem. Soc., 1986, 105, 5078. [all data]
Dallos, Sisak, et al., 2000
Dallos, A.; Sisak, A.; Kulcsár, Z.; Kováts, E.,
Pair-wise interactions by gas chromatography VII. Interaction free enthalpies of solutes with secondary alcohol groups,
J. Chromatogr. A, 2000, 904, 2, 211-242, https://doi.org/10.1016/S0021-9673(00)00908-0
. [all data]
Reddy, Dutoit, et al., 1992
Reddy, K.S.; Dutoit, J.-Cl.; Kovats, E. sz.,
Pair-wise interactions by gas chromatography. I. Interaction free enthalpies of solutes with non-associated primary alcohol groups,
J. Chromatogr., 1992, 609, 1-2, 229-259, https://doi.org/10.1016/0021-9673(92)80167-S
. [all data]
Safina, Poznyak, et al., 1989
Safina, L.R.; Poznyak, T.I.; Lisitsyn, D.M.; Kiseleva, E.V.; Kovalev, G.I.,
Selective gas-chromatographic determination of trace unsaturated and aromatic-hydrocarbons in complex-mixtures,
J. Appl. Chem. USSR (Engl. Transl.), 1989, 44, 5, 749-754. [all data]
Engewald, Billing, et al., 1987
Engewald, W.; Billing, U.; Welsch, T.; Haufe, G.,
Structure-retention correlations of hydrocarbons in gas-liquid and gas-solid chromatography. Cycloalkenes and cycloalkadienes,
Chromatographia, 1987, 23, 8, 590-594, https://doi.org/10.1007/BF02324870
. [all data]
Bredael, 1982
Bredael, P.,
Retention indices of hydrocarbons on SE-30,
J. Hi. Res. Chromatogr. Chromatogr. Comm., 1982, 5, 6, 325-328, https://doi.org/10.1002/jhrc.1240050610
. [all data]
Morishita, Okano, et al., 1980
Morishita, F.; Okano, T.; Kojima, T.,
Retention indices of monocyclic monoterpene hydrocarbons,
Bunseki Kagaku, 1980, 29, 1, 48-53, https://doi.org/10.2116/bunsekikagaku.29.48
. [all data]
Bajus, Veselý, et al., 1979
Bajus, M.; Veselý, V.; Leclercq, P.A.; Rijks, J.A.,
Steam cracking of hydrocarbons. 2. Pyrolysis of methylcyclohexane,
Ind. Eng. Chem. Prod. Res. Dev., 1979, 18, 2, 135-142, https://doi.org/10.1021/i360070a012
. [all data]
Bogoslovsky, Anvaer, et al., 1978
Bogoslovsky, Yu.N.; Anvaer, B.I.; Vigdergauz, M.S.,
Chromatographic constants in gas chromatography (in Russian), Standards Publ. House, Moscow, 1978, 192. [all data]
Engewald, Epsch, et al., 1974
Engewald, W.; Epsch, K.; Graefe, J.; Welsch, Th.,
Molekülstruktur und retentionsverhalten. II. Retentionsverhalten cycloaliphatischer kohlenwasser-stoffe bei der gas-adsorptions- und gas-verteilungschromatographie,
J. Chromatogr., 1974, 91, 623-631, https://doi.org/10.1016/S0021-9673(01)97943-9
. [all data]
Robinson and Odell, 1971
Robinson, P.G.; Odell, A.L.,
A system of standard retention indices and its uses. The characterisation of stationary phases and the prediction of retention indices,
J. Chromatogr., 1971, 57, 1-10, https://doi.org/10.1016/0021-9673(71)80001-8
. [all data]
Hively and Hinton, 1968
Hively, R.A.; Hinton, R.E.,
Variation of the retention index with temperature on squalane substrates,
J. Gas Chromatogr., 1968, 6, 4, 203-217, https://doi.org/10.1093/chromsci/6.4.203
. [all data]
Schomburg, 1966
Schomburg, G.,
Gaschromatographische Retentionsdaten und struktur chemischer verbindungen. III. Alkylverzweigte und ungesättigte cyclische Kohlenwasserstoffe,
J. Chromatogr., 1966, 23, 18-41, https://doi.org/10.1016/S0021-9673(01)98653-4
. [all data]
Umano and Shibamoto, 1987
Umano, K.; Shibamoto, T.,
Analysis of headspace volatiles from overheated beef fat,
J. Agric. Food Chem., 1987, 35, 1, 14-18, https://doi.org/10.1021/jf00073a004
. [all data]
White, Hackett, et al., 1992
White, C.M.; Hackett, J.; Anderson, R.R.; Kail, S.; Spock, P.S.,
Linear temperature programmed retention indices of gasoline range hydrocarbons and chlorinated hydrocarbons on cross-linked polydimethylsiloxane,
J. Hi. Res. Chromatogr., 1992, 15, 2, 105-120, https://doi.org/10.1002/jhrc.1240150211
. [all data]
Buchman, Cao, et al., 1984
Buchman, O.; Cao, G.-Y.; Peng, C.T.,
Structure assignment by retention index in gas-liquid radiochromatography of substituted cyclohexenes,
J. Chromatogr., 1984, 312, 75-90, https://doi.org/10.1016/S0021-9673(01)92765-7
. [all data]
Peng, Ding, et al., 1988
Peng, C.T.; Ding, S.F.; Hua, R.L.; Yang, Z.C.,
Prediction of Retention Indexes I. Structure-Retention Index Relationship on Apolar Columns,
J. Chromatogr., 1988, 436, 137-172, https://doi.org/10.1016/S0021-9673(00)94575-8
. [all data]
Schomburg, 1966, 2
Schomburg, G.,
Gaschromatographische Retentionsdaten und Struktur Chemischer Verbindungen. II. Methylverzweigungen und Doppelbindungen in Offenkettigen Kohlenwasserstoffen,
J. Chromatogr., 1966, 23, 1-17, https://doi.org/10.1016/S0021-9673(01)98652-2
. [all data]
Supelco, 2012
Supelco, CatalogNo. 24160-U,
Petrocol DH Columns. Catalog No. 24160-U, 2012, retrieved from http://www.sigmaaldrich.com/etc/medialib/docs/Supelco/Datasheet/1/w97949.Par.0001.File.tmp/w97949.pdf. [all data]
Zhang, Ding, et al., 2009
Zhang, X.; Ding, L.; Sun, Z.; Song, L.; Sun, T.,
Study on quantitative structure-retention relationships for hydrocarbons in FCC gasoline,
Chromatographia, 2009, 70, 3/4, 511-518, https://doi.org/10.1365/s10337-009-1174-0
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Orav, Kailas, et al., 1999
Orav, A.; Kailas, T.; Muurisepp, M.; Kann, J.,
Composition of the oil from waste tires. 1. Fraction boiling at yp to 160 0C,
Proc. Estonian Acad. Sci. Chem., 1999, 48, 1, 30-39. [all data]
Chen, 2008
Chen, H.-F.,
Quantitative prediction of gas chromatography retention indices with support vector machines, radial basis neutral networks and multiple linear regression,
Anal. Chim. Acta, 2008, 609, 1, 24-36, https://doi.org/10.1016/j.aca.2008.01.003
. [all data]
Zenkevich, 1998
Zenkevich, I.G.,
Application of Methods of Molecular Dynamics in Chromato-Spectral Identification of ISomeric Products of Organic reactions (in Russian),
Zh. Org. Khim., 1998, 34, 10, 1463-1470. [all data]
Waggott and Davies, 1984
Waggott, A.; Davies, I.W.,
Identification of organic pollutants using linear temperature programmed retention indices (LTPRIs) - Part II, 1984, retrieved from http://dwi.defra.gov.uk/research/completed-research/reports/dwi0383.pdf. [all data]
Peng, Yang, et al., 1991
Peng, C.T.; Yang, Z.C.; Ding, S.F.,
Prediction of rentention idexes. II. Structure-retention index relationship on polar columns,
J. Chromatogr., 1991, 586, 1, 85-112, https://doi.org/10.1016/0021-9673(91)80028-F
. [all data]
Notes
Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, References
- Symbols used in this document:
AE Appearance energy ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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