2-Pentene, 4-methyl-, (E)-

Formula: C₆H₁₂
Molecular weight: 84.1595
IUPAC Standard InChI: InChI=1S/C6H12/c1-4-5-6(2)3/h4-6H,1-3H3/b5-4+
IUPAC Standard InChIKey: LGAQJENWWYGFSN-SNAWJCMRSA-N
CAS Registry Number: 674-76-0
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.
Stereoisomers:
- 2-Pentene, 4-methyl-
- 2-Pentene, 4-methyl-, (Z)-
Other names: (E)-4-Methyl-2-pentene; trans-4-Methyl-2-Pentene; 4-Methyl-trans-2-pentene; (E)-(CH3)2CHCH=CHCH3; 4-Methyl-2-pentene, (E)-; 4-Methyl-2-pentene, trans-; 4-Methylpentene-2, trans-; (E)-4-methylpent-2-ene
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Other data available:
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Phase change data

Go To: Top, Gas phase ion energetics data, Gas Chromatography, References, Notes

Data compiled as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity	Value	Units	Method	Reference	Comment
T_boil	331.5 ± 0.6	K	AVG	N/A	Average of 12 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_vapH°	7.17	kcal/mol	N/A	Reid, 1972	AC
Δ_vapH°	7.16	kcal/mol	V	Camin and Rossini, 1956	ALS
Δ_vapH°	7.17	kcal/mol	N/A	Camin and Rossini, 1956, 2	Based on data from 291. to 332. K.; AC

Enthalpy of vaporization

Δ_vapH (kcal/mol)	Temperature (K)	Method	Reference	Comment
7.46	284.	A	Stephenson and Malanowski, 1987	Based on data from 269. to 337. K.; AC

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:

Gas phase ion energetics data

Go To: Top, Phase change data, Gas Chromatography, References, Notes

Data evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

View reactions leading to C₆H₁₂⁺ (ion structure unspecified)

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	8.97 ± 0.01	eV	N/A	N/A	L

Ionization energy determinations

IE (eV)	Method	Reference	Comment
8.91	EI	Lossing and Traeger, 1975	LLK
8.972 ± 0.005	PE	Masclet, Grosjean, et al., 1973	LLK

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
C₅H₉⁺	8.91	CH₃	EI	Lossing and Traeger, 1975, 2	LLK
C₅H₉⁺	10.17	CH₃	EI	Lossing and Traeger, 1975	LLK

Gas Chromatography

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

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

Kovats' RI, non-polar column, isothermal

View large format table.

Column type	Active phase	Temperature (C)	I	Reference	Comment
Capillary	Methyl Silicone	30.	570.4	Soják, Addová, et al., 2002	He; Column length: 150. m; Column diameter: 0.250 mm
Capillary	Squalane	30.	561.9	Soják, Addová, et al., 2002	He; Column length: 93. m; Column diameter: 0.250 mm
Capillary	OV-101	40.	569.	Laub and Purnell, 1988
Capillary	OV-101	60.	569.	Laub and Purnell, 1988
Capillary	OV-101	80.	569.	Laub and Purnell, 1988
Capillary	Squalane	50.	561.7	Papazova, Milina, et al., 1988	Column length: 50. m; Column diameter: 0.25 mm
Capillary	OV-101	50.	569.1	Boneva and Dimov, 1986	100. m/0.27 mm/0.9 μm, N2
Capillary	OV-101	70.	568.8	Boneva and Dimov, 1986	100. m/0.27 mm/0.9 μm, N2
Capillary	Squalane	50.	562.1	Boneva and Dimov, 1986	N2; Column length: 100. m; Column diameter: 0.25 mm
Capillary	Squalane	70.	561.9	Boneva and Dimov, 1986	N2; Column length: 100. m; Column diameter: 0.25 mm
Capillary	DB-1	40.	570.	Lubeck and Sutton, 1984	60. m/0.264 mm/0.25 μm, H2
Capillary	HP-PONA	40.	570.	Lubeck and Sutton, 1984	50. m/0.21 mm/0.5 μm, H2
Capillary	Squalane	50.	563.	Mitra, 1981	N2; Column length: 100. m; Column diameter: 0.25 mm
Capillary	Squalane	50.	563.	Mitra, 1981	N2; Column length: 100. m; Column diameter: 0.25 mm
Capillary	Squalane	50.	561.9	Bajus, Veselý, et al., 1979	Column length: 100. m; Column diameter: 0.25 mm
Packed	Squalane	80.	562.	Chrétien and Dubois, 1977
Capillary	Squalane	50.	562.	Chretien and Dubois, 1976
Capillary	Squalane	100.	565.8	Lulova, Leont'eva, et al., 1976	He; Column length: 120. m; Column diameter: 0.25 mm
Capillary	Squalane	50.	562.	Rijks and Cramers, 1974	N2; Column length: 100. m; Column diameter: 0.25 mm
Capillary	Squalane	70.	562.	Rijks and Cramers, 1974	N2; Column length: 100. m; Column diameter: 0.25 mm
Capillary	Squalane	27.	561.80	Schomburg and Dielmann, 1973	Column length: 100. m; Column diameter: 0.25 mm
Packed	SE-30	75.	567.	Robinson and Odell, 1971	N2, Chromosorb W; Column length: 6.1 m
Packed	Squalane	100.	557.	Robinson and Odell, 1971	N2, Embacel; Column length: 3.0 m
Capillary	Squalane	40.	565.	Matukuma, 1969	N2; Column length: 91.4 m; Column diameter: 0.25 mm
Packed	Squalane	27.	562.	Hively and Hinton, 1968	He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm
Packed	Squalane	49.	562.	Hively and Hinton, 1968	He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm
Packed	Squalane	67.	563.	Hively and Hinton, 1968	He, Chromosorb P; Column length: 15. m; Column diameter: 0.25 mm
Capillary	Squalane	70.	563.	Schomburg, 1967	Ar; Column length: 100. m
Packed	SE-30	70.	570.	Widmer, 1967	Diatoport S; Column length: 7.9 m
Packed	Squalane	26.	558.	Zulaïca and Guiochon, 1966	Column length: 10. m
Packed	Apiezon L	130.	559.	Wehrli and Kováts, 1959	Celite; Column length: 2.25 m
Packed	Apiezon L	70.	557.	Wehrli and Kováts, 1959	Celite; Column length: 2.25 m

Kovats' RI, non-polar column, custom temperature program

View large format table.

Column type	Active phase	I	Reference	Comment
Capillary	Petrocol DH-100	575.5	Haagen-Smit Laboratory, 1997	He; Column length: 100. m; Column diameter: 0.2 mm; Program: 5C(10min) => 5C/min => 50C(48min) => 1.5C/min => 195C(91min)
Capillary	DB-1	575.	Hoekman, 1993	60. m/0.32 mm/1.0 μm, He; Program: -40 C for 12 min; -40 - 125 C at 3 deg.min; 125-185 C at 6 deg/min; 185 - 220 C at 20 deg/min; hold 220 C for 2 min

Kovats' RI, polar column, isothermal

View large format table.

Column type	Active phase	Temperature (C)	I	Reference	Comment
Packed	Carbowax 20M	130.	592.	Widmer, 1967	Diatoport P; Column length: 7.9 m
Packed	Carbowax 20M	70.	590.	Widmer, 1967	Diatoport P; Column length: 7.9 m

Van Den Dool and Kratz RI, non-polar column, temperature ramp

View large format table.

Column type	Active phase	I	Reference	Comment
Capillary	Methyl Silicone	568.7	Soják, Addová, et al., 2002	He, 1. K/min; Column length: 150. m; Column diameter: 0.250 mm; T_start: 30. C; T_end: 200. C
Capillary	Petrocol DH	562.	White, Hackett, et al., 1992	100. m/0.25 mm/0.5 μm, He, 1. K/min; T_start: 30. C; T_end: 220. C

Normal alkane RI, non-polar column, isothermal

View large format table.

Column type	Active phase	Temperature (C)	I	Reference	Comment
Capillary	Squalane	40.	561.7	Sojak, Addova, et al., 2000	He; Column length: 93. m; Column diameter: 0.25 mm
Capillary	Methyl Silicone	50.	562.	N/A	N2; Column length: 74.6 m; Column diameter: 0.28 mm
Capillary	Squalane	70.	563.	Schomburg, 1966
Packed	Methyl Silicone	50.	572.	Huguet, 1961	Nitrogen, Celite C-22; Column length: 2.5 m

Normal alkane RI, non-polar column, temperature ramp

View large format table.

Column type	Active phase	I	Reference	Comment
Capillary	Polydimethyl siloxane: CP-Sil 5 CB	571.	Bramston-Cook, 2013	60. m/0.25 mm/1.0 μm, Helium, 45. C @ 1.45 min, 3.6 K/min, 210. C @ 2.72 min
Capillary	Petrocol DH	572.	Supelco, 2012	100. m/0.25 mm/0.50 μm, Helium, 20. C @ 15. min, 15. K/min, 220. C @ 30. min
Capillary	OV-101	571.	Orav, Kailas, et al., 1999	50. m/0.20 mm/0.50 μm, Helium, 30. C @ 6. min, 1. K/min; T_end: 100. C
Capillary	SE-54	547.	Guan, Li, et al., 1995	60. C @ 2. min, 4. K/min; Column length: 50. m; Column diameter: 0.32 mm; T_end: 200. C
Capillary	DB-1	569.	Ramnas, Ostermark, et al., 1994	50. m/0.32 mm/1.0 μm, He, 2. K/min; T_start: -20. C

Normal alkane RI, non-polar column, custom temperature program

View large format table.

Column type	Active phase	I	Reference	Comment
Capillary	Polydimethyl siloxane	562.	Junkes, Castanho, et al., 2003	Program: not specified
Capillary	PONA	575.	Perkin Elmer Instruments, 2002	Column length: 100. m; Phase thickness: 0.50 μm; Program: not specified
Capillary	Methyl Silicone	568.	Zenkevich and Marinichev, 2001	Program: not specified
Capillary	Methyl Silicone	573.	Spieksma, 1999	Program: not specified
Packed	SE-30	574.	Robinson and Odell, 1971	N2, Chromosorb W; Column length: 6.1 m; Program: 50C910min) => 20C/min => 90(6min) => 10C/min => 150C(hold)

References

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

Reid, 1972
Reid, Robert C., Handbook on vapor pressure and heats of vaporization of hydrocarbons and related compounds, R. C. Wilhort and B. J. Zwolinski, Texas A Research Foundation. College Station, Texas(1971). 329 pages.$10.00, AIChE J., 1972, 18, 6, 1278-1278, https://doi.org/10.1002/aic.690180637 . [all data]

Camin and Rossini, 1956
Camin, D.L.; Rossini, F.D., Physical properties of the 17 isomeric hexenes of the API research series, J. Phys. Chem., 1956, 60, 1446. [all data]

Camin and Rossini, 1956, 2
Camin, David L.; Rossini, Frederick D., Physical Properties of the 17 Isomeric Hexenes.of the API Research Series, J. Phys. Chem., 1956, 60, 10, 1446-1451, https://doi.org/10.1021/j150544a029 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Lossing and Traeger, 1975
Lossing, F.P.; Traeger, J.C., Stabilization in cyclopentadienyl, cyclopentenyl, and cyclopentyl cations, J. Am. Chem. Soc., 1975, 97, 1579. [all data]

Masclet, Grosjean, et al., 1973
Masclet, P.; Grosjean, D.; Mouvier, G., Alkene ionization potentials. Part I. Quantitative determination of alkyl group structural effects, J. Electron Spectrosc. Relat. Phenom., 1973, 2, 225. [all data]

Lossing and Traeger, 1975, 2
Lossing, F.P.; Traeger, J.C., Free radicals by mass spectrometry XLVI. Heats of formation of C₅H₇ and C₅H₉ radicals and cations., J. Am. Chem. Soc., 1975, 19, 9. [all data]

Soják, Addová, et al., 2002
Soják, L.; Addová, G.; Kubinec, R.; Kraus, A.; Hu, G., Gas chromatographic-mass spectrometric characterization of all acyclic C₅-C₇ alkenes from fluid catalytic cracked gasoline using polydimethylsiloxane and squalane stationary phases, J. Chromatogr. A, 2002, 947, 1, 103-117, https://doi.org/10.1016/S0021-9673(01)01564-3 . [all data]

Laub and Purnell, 1988
Laub, R.J.; Purnell, J.H., Specific retention volumes, retention indices, and family-plot regressions of aliphatic, alicyclic, and aromatic hydrocarbon solutes with OV-101 poly (dimethylsiloxane) stationary phase, J. Hi. Res. Chromatogr. Chromatogr. Comm., 1988, 11, 9, 649-660, https://doi.org/10.1002/jhrc.1240110908 . [all data]

Papazova, Milina, et al., 1988
Papazova, D.; Milina, R.; Dimov, N., Comparative evaluation of retention of hydrocarbons present in the C₅-petroleum fraction of methylsilicone and squalane phases, Chromatographia, 1988, 25, 3, 177-180, https://doi.org/10.1007/BF02316441 . [all data]

Boneva and Dimov, 1986
Boneva, S.; Dimov, N., Gas Chromatographic Retention Indices for Alkenes on OV-101 and Squalane Capillary Columns, Chromatographia, 1986, 21, 3, 149-151, https://doi.org/10.1007/BF02311743 . [all data]

Lubeck and Sutton, 1984
Lubeck, A.J.; Sutton, D.L., Kovats Retention Indices of Selected Olefins on Bonded Phase Fused Silica Capillaries, J. Hi. Res. Chromatogr. Chromatogr. Comm., 1984, 7, 9, 542-544, https://doi.org/10.1002/jhrc.1240070913 . [all data]

Mitra, 1981
Mitra, G.D., Conversion of linear retention indices into logarithmic retention indices, J. Chromatogr., 1981, 211, 2, 239-242, https://doi.org/10.1016/S0021-9673(00)88039-5 . [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]

Chrétien and Dubois, 1977
Chrétien, J.R.; Dubois, J.E., Topological analysis of gas-liquid chromatographic behavior of alkenes, Anal. Chem., 1977, 49, 6, 747-756, https://doi.org/10.1021/ac50014a021 . [all data]

Chretien and Dubois, 1976
Chretien, J.R.; Dubois, J.-E., New Perspectives in the Prediction of Kovats Indices, J. Chromatogr., 1976, 126, 171-189, https://doi.org/10.1016/S0021-9673(01)84071-1 . [all data]

Lulova, Leont'eva, et al., 1976
Lulova, N.I.; Leont'eva, S.A.; Timofeeva, A.N., Gas-chromatographic method of determination of individual hydrocarbons in catalytic cracking gasolines in Proceedings of All-Union Research Institute on Oil Processes. Vol.18, All-Union Research Institute on Oil Processes, Moscow, 1976, 30-53. [all data]

Rijks and Cramers, 1974
Rijks, J.A.; Cramers, C.A., High precision capillary gas chromatography of hydrocarbons, Chromatographia, 1974, 7, 3, 99-106, https://doi.org/10.1007/BF02269819 . [all data]

Schomburg and Dielmann, 1973
Schomburg, G.; Dielmann, G., Identification by means of retention parameters, J. Chromatogr. Sci., 1973, 11, 3, 151-159, https://doi.org/10.1093/chromsci/11.3.151 . [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]

Matukuma, 1969
Matukuma, A., Retention indices of alkanes through C₁₀ and alkenes through C₈ and relation between boiling points and retention data, Gas Chromatogr., Int. Symp. Anal. Instrum. Div Instrum Soc. Amer., 1969, 7, 55-75. [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, 1967
Schomburg, G., Struktur und Retentionsverhalten von Offenkettigen und Cyclischen Kohlenwasserstoffen und Deren Einfacher Substitutionsprodukte, Anal. Chim. Acta., 1967, 38, 45-64, https://doi.org/10.1016/S0003-2670(01)80560-2 . [all data]

Widmer, 1967
Widmer, H., Gas chromatographic identification of hydrocarbons using retention indices, J. Gas Chromatogr., 1967, 5, 10, 506-510, https://doi.org/10.1093/chromsci/5.10.506 . [all data]

Zulaïca and Guiochon, 1966
Zulaïca, J.; Guiochon, G., Analyse des hauts polymères par chromatographie en phase gazeuse de leurs produits de pyrolyse. II. Application à quelques hydrocarbures macromoléculaires purs, Bull. Soc. Chim. Fr., 1966, 4, 1351-1363. [all data]

Wehrli and Kováts, 1959
Wehrli, A.; Kováts, E., Gas-chromatographische Charakterisierung ogranischer Verbindungen. Teil 3: Berechnung der Retentionsindices aliphatischer, alicyclischer und aromatischer Verbindungen, Helv. Chim. Acta, 1959, 7, 7, 2709-2736, https://doi.org/10.1002/hlca.19590420745 . [all data]

Haagen-Smit Laboratory, 1997
Haagen-Smit Laboratory, Procedure for the detailed hydrocarbon analysis of gasolines by single column high efficiency (capillary) column gas chromatography, SOP NO. MLD 118, Revision No. 1.1, California Environmental Protection Agency, Air Resources Board, El Monte, California, 1997, 22. [all data]

Hoekman, 1993
Hoekman, S.K., Improved gas chromatography procedure for speciated hydrocarbon measurements of vehicle emissions, J. Chromatogr., 1993, 639, 2, 239-253, https://doi.org/10.1016/0021-9673(93)80260-F . [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]

Sojak, Addova, et al., 2000
Sojak, L.; Addova, G.; Kubinec, R.; Ruman, J.; Hu, G., GC-MS characterization of all acyclic C5-C7 alkenes from FCC gasoline using squalane stationary phase, Petroleum and Coal, 2000, 42, 3-4, 188-194. [all data]

Schomburg, 1966
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]

Huguet, 1961
Huguet, M., Kovats retention indices in the qualitative analysis of light hydrocarbons by gas chromatography, Journees internationales d'etude des methodes de separation immediate et de chromatographie, 1961, 69. [all data]

Bramston-Cook, 2013
Bramston-Cook, R., Kovats indices for C2-C13 hydrocarbons and selected oxygenated/halocarbons with 100 % dimethylpolysiloxane columns, 2013, retrieved from http://lotusinstruments.com/monographs/List .... [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]

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]

Guan, Li, et al., 1995
Guan, Y.; Li, L.; Zhou, L., Live retention database for compound identification in capillary gas chromatography, Chin. J. Chromatogr., 1995, 13, 5, 851-857. [all data]

Ramnas, Ostermark, et al., 1994
Ramnas, O.; Ostermark, U.; Peterson, G., Characterization of sixty alkenes in a cat-cracked gasoline naphtha by gas chromatography, Chromatographia, 1994, 38, 3/4, 222-226, https://doi.org/10.1007/BF02290340 . [all data]

Junkes, Castanho, et al., 2003
Junkes, B.S.; Castanho, R.D.M.; Amboni, C.; Yunes, R.A.; Heinzen, V.E.F., Semiempirical Topological Index: A Novel Molecular Descriptor for Quantitative Structure-Retention Relationship Studies, Internet Electronic Journal of Molecular Design, 2003, 2, 1, 33-49. [all data]

Perkin Elmer Instruments, 2002
Perkin Elmer Instruments, Detailed hydrocarbon analysis (DHAX) Model 4015, 2002, retrieved from http://www.perkinelmer.com/instruments. [all data]

Zenkevich and Marinichev, 2001
Zenkevich, I.G.; Marinichev, A.N., Comparison of Topological and Dynamics Molecular Characteristics for Precalculation of Chromatographic Retention Parameters of Organic Compounds (in Russian), Zh. Struct. Khim., 2001, 42, 5, 893-902. [all data]

Spieksma, 1999
Spieksma, W., Determination of vapor liquid equilibrium from the Kovats retention index on dimethylsilicone using the Wilson mixing tool, J. Hi. Res. Chromatogr., 1999, 22, 10, 565-588, https://doi.org/10.1002/(SICI)1521-4168(19991001)22:10<565::AID-JHRC565>3.0.CO;2-2 . [all data]

Notes

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

Symbols used in this document:

AE Appearance energy

IE (evaluated) Recommended ionization energy

T_boil Boiling point

Δ_vapH Enthalpy of vaporization

Δ_vapH° Enthalpy of vaporization at standard conditions
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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AE	Appearance energy
IE (evaluated)	Recommended ionization energy
T_boil	Boiling point
Δ_vapH	Enthalpy of vaporization
Δ_vapH°	Enthalpy of vaporization at standard conditions