Benzene, 1-methyl-4-nitro-
- Formula: C7H7NO2
- Molecular weight: 137.1360
- IUPAC Standard InChIKey: ZPTVNYMJQHSSEA-UHFFFAOYSA-N
- CAS Registry Number: 99-99-0
- 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. - Species with the same structure:
- Other names: Toluene, p-nitro-; p-Methylnitrobenzene; p-Nitrotoluene; PNT; 1-Methyl-4-nitrobenzene; 4-Methylnitrobenzene; 4-Nitrotoluene; 4-Nitrotoluol; NCI-C60537; NSC 9579
- Information on this page:
- Other data available:
- Data at other public NIST sites:
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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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to C7H7NO2+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.46 ± 0.05 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 194.8 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 187.1 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
0.95 ± 0.10 | IMRE | Chowdhury, Heinis, et al., 1986 | ΔGea(423 K) = -21.2 kcal/mol; ΔSea (estimated) = -2.0 eu.; B |
0.971 ± 0.048 | IMRE | Fukuda and McIver, 1985 | ΔGea(355 K) = -21.7 kcal/mol; ΔSea =-2.0, est. from data in Chowdhury, Heinis, et al., 1986; B |
0.932 ± 0.087 | IMRE | Huh, Kang, et al., 1999 | ΔG(EA) 343K; anchored to ΔG value. Including anchor ΔS, EA is ca. 0.4 kcal/mol more bound.; B |
0.960 ± 0.030 | ECD | Chen, Chen, et al., 1992 | B |
<1.100 ± 0.050 | PD | Mock and Grimsrud, 1989 | B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.46 ± 0.05 | PIPECO | Baer, Morrow, et al., 1988 | LL |
9.1 ± 0.1 | PE | Egdell, Green, et al., 1975 | LLK |
9.56 | EI | Johnstone and Mellon, 1973 | LLK |
9.76 ± 0.05 | EI | Buchs, 1970 | RDSH |
9.5 ± 0.1 | EI | Brown, 1970 | RDSH |
9.52 | PE | Kobayashi and Nagakura, 1974 | Vertical value; LLK |
9.54 ± 0.015 | PE | Kobayashi and Nagakura, 1972 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C5H5+ | 14.9 ± 0.2 | C2H2+NO2 | EI | Tajima and Tsuchiya, 1973 | LLK |
C7H7+ | 11.08 | NO2 | PIPECO | Baer, Morrow, et al., 1988 | T = 0K; LL |
C7H7+ | 11.15 | NO2 | PIPECO | Baer, Morrow, et al., 1988 | T = 298K; LL |
C7H7+ | 11.3 ± 0.1 | NO2 | PI | Matyuk, Potapov, et al., 1979 | LLK |
C7H7+ | 12.3 ± 0.3 | NO2 | EI | McLafferty and Winkler, 1974 | LLK |
C7H7+ | 11.8 ± 0.1 | NO2 | EI | Brown, 1970 | RDSH |
C7H7O+ | 10.91 ± 0.05 | NO | PI | Matyuk, Potapov, et al., 1979 | LLK |
C7H7O+ | 10.3 ± 0.1 | NO | EI | Brown, 1970 | RDSH |
De-protonation reactions
C7H6NO2- + =
By formula: C7H6NO2- + H+ = C7H7NO2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 352.5 ± 2.1 | kcal/mol | G+TS | Taft and Topsom, 1987 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 353.1 ± 2.4 | kcal/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 345.3 ± 2.0 | kcal/mol | IMRE | Taft and Topsom, 1987 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 345.9 ± 2.0 | kcal/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; B |
Ion clustering 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:
B - John E. Bartmess
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. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
By formula: Br- + C7H7NO2 = (Br- • C7H7NO2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 16.2 ± 1.8 | kcal/mol | IMRE | Paul and Kebarle, 1991 | gas phase; ΔGaff measured at 303 K, corrected to 423 K, ΔSaff taken as that of mCF3-nitrobenzene..Br-; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 22. | cal/mol*K | N/A | Paul and Kebarle, 1991 | gas phase; Entropy change calculated or estimated; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 6.8 ± 1.0 | kcal/mol | IMRE | Paul and Kebarle, 1991 | gas phase; ΔGaff measured at 303 K, corrected to 423 K, ΔSaff taken as that of mCF3-nitrobenzene..Br-; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
6.8 | 423. | PHPMS | Paul and Kebarle, 1991 | gas phase; Entropy change calculated or estimated; M |
By formula: Cl- + C7H7NO2 = (Cl- • C7H7NO2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrG° | 7.50 | kcal/mol | TDEq | French, Ikuta, et al., 1982 | gas phase; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
7.5 | 300. | PHPMS | French, Ikuta, et al., 1982 | gas phase; M |
IR Spectrum
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Data compiled by: Coblentz Society, Inc.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
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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Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
Due to licensing restrictions, this spectrum cannot be downloaded.
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-6817 |
NIST MS number | 228474 |
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.
Spectrum
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Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
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Download spectrum in JCAMP-DX format.
Source | Lang (editor), 1965 |
---|---|
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. 19988 |
Instrument | Unicam SP 500 |
Melting point | 54 |
Gas Chromatography
Go To: Top, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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 | Apiezon L | 130. | 1212. | Wehrli and Kováts, 1959 | Celite; Column length: 2.25 m |
Kovats' RI, polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Packed | Carbowax 20M | 200. | 1986. | Vernon and Suratman, 1983 | He, Silanized white support; Column length: 2. m |
Normal alkane RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | ZB-1 | 1167. | Harvey and Wenzel, 2009 | 15. m/0.25 mm/0.10 μm, Helium, 4. K/min, 185. C @ 15. min; Tstart: 35. C |
Capillary | ZB-1 | 1170. | Harvey and Wenzel, 2009 | 15. m/0.25 mm/0.10 μm, Helium, 4. K/min, 185. C @ 15. min; Tstart: 35. C |
Capillary | ZB-1 | 1195. | Harvey and Wenzel, 2009 | 15. m/0.25 mm/0.10 μm, Helium, 4. K/min, 185. C @ 15. min; Tstart: 35. C |
Lee's RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | DB-5MS | 205.47 | Chen, Keeran, et al., 2002 | 30. m/0.25 mm/0.5 μm, 40. C @ 1. min, 10. K/min; Tend: 310. C |
References
Go To: Top, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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]
Chowdhury, Heinis, et al., 1986
Chowdhury, S.; Heinis, T.; Grimsrud, E.P.; Kebarle, P.,
Entropy Changes and Electron Affinities from Gas-Phase Electron Transfer Equilibria: A- + B = A + B-,
J. Phys. Chem., 1986, 90, 12, 2747, https://doi.org/10.1021/j100403a037
. [all data]
Fukuda and McIver, 1985
Fukuda, E.K.; McIver, R.T., Jr.,
Relative electron affinities of substituted benzophenones, nitrobenzenes, and quinones. [Anchored to EA(SO2) from 74CEL/BEN],
J. Am. Chem. Soc., 1985, 107, 2291. [all data]
Huh, Kang, et al., 1999
Huh, C.; Kang, C.H.; Lee, H.W.; Nakamura, H.; Mishima, M.; Tsuno, Y.; Yamataka, H.,
Thermodynamic stabilities and resonance demand of aromatic radical anions in the gas phase,
Bull. Chem. Soc. Japan, 1999, 72, 5, 1083-1091, https://doi.org/10.1246/bcsj.72.1083
. [all data]
Chen, Chen, et al., 1992
Chen, E.C.M.; Chen, E.S.; Milligan, M.S.; Wentworth, W.E.; Wiley, J.R.,
Experimental Determination of the Electron Affinities of Nitrobenzene, Nitrotoluenes, Pentafluoronitrobenzene, and Isotopic Nitrobenzenes an,
J. Phys. Chem., 1992, 96, 5, 2385, https://doi.org/10.1021/j100184a069
. [all data]
Mock and Grimsrud, 1989
Mock, R.S.; Grimsrud, E.P.,
Gas-Phase Electron Photodetachment Spectroscopy of the Molecular Anions of Nitroaromatic Hydrocarbons at Atmospheric Pressure,
J. Am. Chem. Soc., 1989, 111, 8, 2861, https://doi.org/10.1021/ja00190a020
. [all data]
Baer, Morrow, et al., 1988
Baer, T.; Morrow, J.C.; Shao, J.D.; Olesik, S.,
Gas-phase heats of formation of C7H7+ isomers: m-Tolyl, p-tolyl, and benzyl ions,
J. Am. Chem. Soc., 1988, 110, 5633. [all data]
Egdell, Green, et al., 1975
Egdell, R.; Green, J.C.; Rao, C.N.R.,
Photoelectron spectra of substituted benzenes,
Chem. Phys. Lett., 1975, 33, 600. [all data]
Johnstone and Mellon, 1973
Johnstone, R.A.W.; Mellon, F.A.,
Effects of induction and resonance in the calculation of ionization potentials of substituted benzenes by perturbation molecular orbital theory,
J. Chem. Soc. Faraday Trans. 2, 1973, 69, 36. [all data]
Buchs, 1970
Buchs, A.,
Etude par spectrometrie de masse de l'ionisation de benzonitriles, de phenylacetonitriles et de N,N-dimethylanilines substitues,
Helv. Chim. Acta, 1970, 53, 2026. [all data]
Brown, 1970
Brown, P.,
Kinetic studies in mass spectrometry. IX. Competing [M-NO2] and [M-NO] reactions in substituted nitrobenzenes. Approximate activation energies from ionization and appearance potentials,
Org. Mass Spectrom., 1970, 4, 533. [all data]
Kobayashi and Nagakura, 1974
Kobayashi, T.; Nagakura, S.,
Photoelectron spectra of substituted benzenes,
Bull. Chem. Soc. Jpn., 1974, 47, 2563. [all data]
Kobayashi and Nagakura, 1972
Kobayashi, T.; Nagakura, S.,
Photoelectron spectra of nitro-compounds,
Chem. Lett., 1972, 903. [all data]
Tajima and Tsuchiya, 1973
Tajima, S.; Tsuchiya, T.,
Energetics consideration of C5H5+ ions produced from various precursors by electron impact,
Bull. Chem. Soc. Jpn., 1973, 46, 3291. [all data]
Matyuk, Potapov, et al., 1979
Matyuk, V.M.; Potapov, V.K.; Prokhoda, A.L.,
Photoexcitation and photoionisation of nitro- derivatives of benzene and toluene,
Russ. J. Phys. Chem., 1979, 53, 538. [all data]
McLafferty and Winkler, 1974
McLafferty, F.W.; Winkler, J.,
Gaseous tropylium, benzyl, tolyl, and norbornadienyl cations,
J. Am. Chem. Soc., 1974, 96, 5182. [all data]
Taft and Topsom, 1987
Taft, R.W.; Topsom, R.D.,
The Nature and Analysis of Substituent Effects,
Prog. Phys. Org. Chem., 1987, 16, 1. [all data]
Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P.,
Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A),
Can. J. Chem., 1978, 56, 1. [all data]
Paul and Kebarle, 1991
Paul, G.J.C.; Kebarle, P.,
Stabilities of Complexes of Br- with Substituted Benzenes (SB) Based on Determinations of the Gas-Phase Equilibria Br- + SB = (BrSB)-,
J. Am. Chem. Soc., 1991, 113, 4, 1148, https://doi.org/10.1021/ja00004a014
. [all data]
French, Ikuta, et al., 1982
French, M.A.; Ikuta, S.; Kebarle, P.,
Hydrogen bonding of O-H and C-H hydrogen donors to Cl-. Results from mass spectrometric measurement of the ion-molecule equilibria RH + Cl- = RHCl-,
Can. J. Chem., 1982, 60, 1907. [all data]
Lang (editor), 1965
Lang (editor), L.,
Absorption Spectra in the Ultraviolet and Visible Region, 1965, 6, 13. [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]
Vernon and Suratman, 1983
Vernon, F.; Suratman, J.B.,
The retention index system applied to alkylbenzenes and monosubstituted derivatives,
Chromatographia, 1983, 17, 11, 600-604, https://doi.org/10.1007/BF02261943
. [all data]
Harvey and Wenzel, 2009
Harvey, S.D.; Wenzel, T.J.,
Selective retention of explosives and related compounds on gas-chromatographic capillary columns coated with lanthanide(III) beta-diketonate polymers,
J. Chromatogr. A, 2009, 1216, 36, 6417-6423, https://doi.org/10.1016/j.chroma.2009.07.008
. [all data]
Chen, Keeran, et al., 2002
Chen, P.H.; Keeran, W.S.; Van Ausdale, W.A.; Schindler, D.R.; Roberts, D.W.,
Application of Lee retention indices to the confirmation of tentatively identified compounds from GC/MS analysis of environmental samples, Technical paper, Analytical Services Division, Environmental ScienceEngineering, Inc, PO Box 1703, Gainesville, FL 32602, 2002, 11. [all data]
Notes
Go To: Top, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Gas Chromatography, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity IE (evaluated) Recommended ionization energy T Temperature ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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