Mequinol
- Formula: C7H8O2
- Molecular weight: 124.1372
- IUPAC Standard InChIKey: NWVVVBRKAWDGAB-UHFFFAOYSA-N
- CAS Registry Number: 150-76-5
- 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: Phenol, 4-methoxy-; Phenol, p-methoxy-; p-Guaiacol; p-Hydroxyanisole; p-Methoxyphenol; Hydroquinone methyl ether; Hydroquinone monomethyl ether; HQMME; Leucobasal; Leucodine B; Mechinolum; Novo-dermoquinona; 1-Hydroxy-4-methoxybenzene; 4-Hydroxyanisole; 4-Methoxyphenol; Monomethyl ether hydroquinone; MME; USAF AN-7; Eastman HQMME; MEHQ; Mequinol (INN); BMS 181158; NSC 4960; p-Hydroxymethoxybenzene; PMF (antioxidant); Hydroxyanisole; Po-hydroxyanisole; Methoxyphenol
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Phase change data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, References, Notes
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:
BS - Robert L. Brown and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 516.2 | K | N/A | Weast and Grasselli, 1989 | BS |
Tboil | 516. | K | N/A | Buckingham and Donaghy, 1982 | BS |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 326. | K | N/A | Buckingham and Donaghy, 1982 | BS |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 22.6 ± 0.29 | kcal/mol | C | Matos, Miranda, et al., 2003 | AC |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
14.7 | 433. | A | Stephenson and Malanowski, 1987 | Based on data from 418. to 518. K. See also Kkykj and Repas, 1973.; AC |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
21.2 | 289. | Stephenson and Malanowski, 1987 | Based on data from 278. to 300. K. See also Aihara, 1960.; AC |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
4.37 | 328.4 | Lee, Chang, et al., 1997 | AC |
Reaction thermochemistry data
Go To: Top, Phase change data, Gas phase ion energetics data, Ion clustering data, References, Notes
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. 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
By formula: Br- + C7H8O2 = (Br- • C7H8O2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 21.0 ± 1.8 | kcal/mol | IMRE | Paul and Kebarle, 1990 | gas phase; ΔGaff at 423 K; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 23. | cal/mol*K | N/A | Paul and Kebarle, 1990 | gas phase; Entropy change calculated or estimated; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 11.3 ± 1.0 | kcal/mol | IMRE | Paul and Kebarle, 1990 | gas phase; ΔGaff at 423 K; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
11.3 | 423. | PHPMS | Paul and Kebarle, 1990 | gas phase; Entropy change calculated or estimated; M |
C7H7O2- + =
By formula: C7H7O2- + H+ = C7H8O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 350.3 ± 2.1 | kcal/mol | G+TS | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 351.1 ± 2.3 | kcal/mol | G+TS | Kebarle and McMahon, 1977 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 343.5 ± 2.0 | kcal/mol | IMRE | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 344.2 ± 2.0 | kcal/mol | IMRE | Kebarle and McMahon, 1977 | gas phase; B |
Gas phase ion energetics data
Go To: Top, Phase change data, Reaction thermochemistry data, Ion clustering data, References, Notes
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
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 C7H8O2+ (ion structure unspecified)
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
7.50 | EI | Cooks, Bertrand, et al., 1973 | LLK |
8.0 ± 0.1 | EI | Brown, 1970 | RDSH |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C6H5O2+ | 11.1 ± 0.1 | CH3 | EI | Brown, 1970 | RDSH |
C6H5O2+ | 11.0 ± 0.1 | CH3 | EI | Tait, Shannon, et al., 1962 | RDSH |
C6H6O+ | 10.30 | HCHO | EI | Cooks, Bertrand, et al., 1973 | LLK |
De-protonation reactions
C7H7O2- + =
By formula: C7H7O2- + H+ = C7H8O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 350.3 ± 2.1 | kcal/mol | G+TS | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 351.1 ± 2.3 | kcal/mol | G+TS | Kebarle and McMahon, 1977 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 343.5 ± 2.0 | kcal/mol | IMRE | Fujio, McIver, et al., 1981 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 344.2 ± 2.0 | kcal/mol | IMRE | Kebarle and McMahon, 1977 | gas phase; B |
Ion clustering data
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References, Notes
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- + C7H8O2 = (Br- • C7H8O2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 21.0 ± 1.8 | kcal/mol | IMRE | Paul and Kebarle, 1990 | gas phase; ΔGaff at 423 K; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 23. | cal/mol*K | N/A | Paul and Kebarle, 1990 | gas phase; Entropy change calculated or estimated; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 11.3 ± 1.0 | kcal/mol | IMRE | Paul and Kebarle, 1990 | gas phase; ΔGaff at 423 K; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
11.3 | 423. | PHPMS | Paul and Kebarle, 1990 | gas phase; Entropy change calculated or estimated; M |
References
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]
Buckingham and Donaghy, 1982
Buckingham, J.; Donaghy, S.M.,
Dictionary of Organic Compounds: Fifth Edition, Chapman and Hall, New York, 1982, 1. [all data]
Matos, Miranda, et al., 2003
Matos, M. Agostinha R.; Miranda, Margarida S.; Morais, Victor M.F.,
Thermochemical Study of the Methoxy- and Dimethoxyphenol Isomers,
J. Chem. Eng. Data, 2003, 48, 3, 669-679, https://doi.org/10.1021/je025641j
. [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]
Kkykj and Repas, 1973
Kkykj, J.; Repas, M.,
Petrochemia, 1973, 13, 179. [all data]
Aihara, 1960
Aihara, Ariyuki,
Estimation of the Energy of Hydrogen Bonds Formed in Crystals. II. Phenols,
Bull. Chem. Soc. Jpn., 1960, 33, 2, 194-200, https://doi.org/10.1246/bcsj.33.194
. [all data]
Lee, Chang, et al., 1997
Lee, Ming-Jer; Chang, Yao-Kun; Lin, Ho-mu; Chen, Chang-Hsin,
Solid-Liquid Equilibria for 4-Methoxyphenol with Catechol, Ethylenediamine, or Piperazine,
J. Chem. Eng. Data, 1997, 42, 2, 349-352, https://doi.org/10.1021/je960201b
. [all data]
Paul and Kebarle, 1990
Paul, G.J.C.; Kebarle, P.,
Stabilities in the Gas Phase of the Hydrogen Bonded Complexes, YC6H4OH-X-, of Substituted Phenols, YC6H4OH, with the Halide Anions X-(Cl-, Br-),
Can. J. Chem., 1990, 68, 11, 2070, https://doi.org/10.1139/v90-316
. [all data]
Fujio, McIver, et al., 1981
Fujio, M.; McIver, R.T., Jr.; Taft, R.W.,
Effects on the acidities of phenols from specific substituent-solvent interactions. Inherent substituent parameters from gas phase acidities,
J. Am. Chem. Soc., 1981, 103, 4017. [all data]
Kebarle and McMahon, 1977
Kebarle, P.; McMahon, T.B.,
Intrinsic Acidities of Substituted Phenols and Benzoic Acids Determined by Gas Phase Proton Transfer Equilibria,
J. Am. Chem. Soc., 1977, 99, 7, 2222, https://doi.org/10.1021/ja00449a032
. [all data]
Cooks, Bertrand, et al., 1973
Cooks, R.G.; Bertrand, M.; Beynon, J.H.; Rennekamp, M.E.; Setser, D.W.,
Energy partitioning data as an ion structure probe. Substituted anisoles,
J. Am. Chem. Soc., 1973, 95, 1732. [all data]
Brown, 1970
Brown, P.,
Kinetic studies in mass spectrometry. VIII. Competing [M-CH3] and [M-CH2O] reactions in substituted anisoles. Approximate activation energies from ionization appearance potentials,
Org. Mass Spectrom., 1970, 4, 519. [all data]
Tait, Shannon, et al., 1962
Tait, J.M.S.; Shannon, T.W.; Harrison, A.G.,
The structure of substituted C7 ions from benzyl derivatives at the appearance potential threshold,
J. Am. Chem. Soc., 1962, 84, 4. [all data]
Notes
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, References
- Symbols used in this document:
AE Appearance energy T Temperature Tboil Boiling point Tfus Fusion (melting) point ΔfusH Enthalpy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions ΔsubH Enthalpy of sublimation ΔsubH° Enthalpy of sublimation at standard conditions ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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