EtO anion
- Formula: C2H5O-
- Molecular weight: 45.0610
- CAS Registry Number: 16331-64-9
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Reaction thermochemistry data
Go To: Top, 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. 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: C2H5O- + C2H6O = (C2H5O- • C2H6O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 27.6 ± 1.0 | kcal/mol | TDEq | Meot-Ner and Sieck, 1986 | gas phase; B,M |
ΔrH° | 28.1 ± 2.5 | kcal/mol | N/A | Caldwell, Rozeboom, et al., 1984 | gas phase; Reanchored to average data from Paul and Kebarle, 1990 and Meot-ner and Sieck, 1986.; value altered from reference due to change in acidity scale; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 26.8 | cal/mol*K | PHPMS | Meot-Ner and Sieck, 1986 | gas phase; M |
ΔrS° | 29.3 | cal/mol*K | N/A | Caldwell, Rozeboom, et al., 1984 | gas phase; switching reaction(CH3O-)CH3OH; Entropy change calculated or estimated; re-evaluated using Meot-Ner(Mautner), 1986 and Paul and Kebarle, 1990; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 19.6 ± 1.6 | kcal/mol | TDEq | Meot-Ner and Sieck, 1986 | gas phase; B |
ΔrG° | 19.0 ± 1.6 | kcal/mol | IMRE | Caldwell, Rozeboom, et al., 1984 | gas phase; Reanchored to average data from Paul and Kebarle, 1990 and Meot-ner and Sieck, 1986.; value altered from reference due to change in acidity scale; B,M |
ΔrG° | 20.1 | kcal/mol | ICR | McIver, Scott, et al., 1973 | gas phase; switching reaction(CH3O-)CH3OH, Entropy change calculated or estimated; Meot-Ner (Mautner), 1992; M |
By formula: C2H5O- + CH4O = (C2H5O- • CH4O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 27.3 ± 2.9 | kcal/mol | IMRE | Caldwell, Rozeboom, et al., 1984 | gas phase; Reanchored to average data from Paul and Kebarle, 1990 and Meot-ner and Sieck, 1986.; value altered from reference due to change in acidity scale; B,M |
ΔrH° | 25.6 ± 1.9 | kcal/mol | CIDT | DeTuri and Ervin, 1999 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 29.3 | cal/mol*K | N/A | Caldwell, Rozeboom, et al., 1984 | gas phase; switching reaction(CH3O-)CH3OH, Entropy change calculated or estimated; re-evaluated using Meot-Ner(Mautner), 1986 and Paul and Kebarle, 1990; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 18.6 ± 2.0 | kcal/mol | IMRE | Caldwell, Rozeboom, et al., 1984 | gas phase; Reanchored to average data from Paul and Kebarle, 1990 and Meot-ner and Sieck, 1986.; value altered from reference due to change in acidity scale; B,M |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
13.4 | 296. | FA | Mackay, Rakshit, et al., 1982 | gas phase; From thermochemical cycle,switching reaction(CH3O-)CH3OH; Caldwell and Kebarle, 1986, Taft, 1983; M |
By formula: C2H5O- + H+ = C2H6O
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 379.2 ± 1.0 | kcal/mol | D-EA | Ramond, Davico, et al., 2000 | gas phase; B |
ΔrH° | 378.0 ± 2.0 | kcal/mol | CIDC | Haas and Harrison, 1993 | gas phase; Both metastable and 50 eV collision energy.; B |
ΔrH° | 377.4 ± 2.1 | kcal/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 379.10 ± 0.10 | kcal/mol | CIDT | DeTuri and Ervin, 1999 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 372.6 ± 1.1 | kcal/mol | H-TS | Ramond, Davico, et al., 2000 | gas phase; B |
ΔrG° | 371.4 ± 2.1 | kcal/mol | H-TS | Haas and Harrison, 1993 | gas phase; Both metastable and 50 eV collision energy.; B |
ΔrG° | 370.8 ± 2.0 | kcal/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
(C2H5O- • 4294967295) + = C2H5O-
By formula: (C2H5O- • 4294967295C2H4O) + C2H4O = C2H5O-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 37.7 ± 1.0 | kcal/mol | N/A | Ramond, Davico, et al., 2000 | gas phase; B |
ΔrH° | 39.5 ± 2.2 | kcal/mol | Ther | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
C2H5O- + = C3H6F3O-
By formula: C2H5O- + CHF3 = C3H6F3O-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 22.0 ± 1.0 | kcal/mol | IMRE | Chabinyc and Brauman, 1998 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 15.1 ± 1.0 | kcal/mol | IMRE | Chabinyc and Brauman, 1998 | gas phase; B |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry 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 by: John E. Bartmess
Electron affinity of neutral species
EAneutral (eV) | Method | Reference | Comment |
---|---|---|---|
1.7120 ± 0.0040 | LPES | Ramond, Davico, et al., 2000 | |
1.7150 ± 0.0070 | LPES | Dang, Motell, et al., 1993 | |
1.726 ± 0.033 | LPES | Ellison, Engleking, et al., 1982 | |
1.79 ± 0.10 | D-EA | Bartmess, Scott, et al., 1979 | value altered from reference due to change in acidity scale |
1.68 ± 0.10 | EIAE | Williams and Hamill, 1968 | From EtONO |
>1.7 | EIAE | Trepka and Neuert, 1963 | From EtOH |
0.589753 | SI | Page and Goode, 1969 | The Magnetron method, lacking mass analysis, is not considered reliable. |
Protonation reactions
By formula: C2H5O- + H+ = C2H6O
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 379.2 ± 1.0 | kcal/mol | D-EA | Ramond, Davico, et al., 2000 | gas phase |
ΔrH° | 378.0 ± 2.0 | kcal/mol | CIDC | Haas and Harrison, 1993 | gas phase; Both metastable and 50 eV collision energy. |
ΔrH° | 377.4 ± 2.1 | kcal/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale |
ΔrH° | 379.10 ± 0.10 | kcal/mol | CIDT | DeTuri and Ervin, 1999 | gas phase |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 372.6 ± 1.1 | kcal/mol | H-TS | Ramond, Davico, et al., 2000 | gas phase |
ΔrG° | 371.4 ± 2.1 | kcal/mol | H-TS | Haas and Harrison, 1993 | gas phase; Both metastable and 50 eV collision energy. |
ΔrG° | 370.8 ± 2.0 | kcal/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Meot-Ner and Sieck, 1986
Meot-Ner, M.; Sieck, L.W.,
The ionic hydrogen bond and ion solvation. 5. OH...O- bonds. Gas phase solvation and clustering of alkoxide and carboxylate anions,
J. Am. Chem. Soc., 1986, 108, 7525. [all data]
Caldwell, Rozeboom, et al., 1984
Caldwell, G.; Rozeboom, M.D.; Kiplinger, J.P.; Bartmess, J.E.,
Anion-alcohol hydrogen bond strengths in the gas phase,
J. Am. Chem. Soc., 1984, 106, 4660. [all data]
Paul and Kebarle, 1990
Paul, G.J.C.; Kebarle, P.,
Thermodynamics of the Association Reactions OH- - H2O = HOHOH- and CH3O- - CH3OH = CH3OHOCH3- in the Gas Phase,
J. Phys. Chem., 1990, 94, 12, 5184, https://doi.org/10.1021/j100375a076
. [all data]
Meot-ner and Sieck, 1986
Meot-ner, M.; Sieck, L.W.,
Relative acidities of water and methanol, and the stabilities of the dimer adducts,
J. Phys. Chem., 1986, 90, 6687. [all data]
Meot-Ner(Mautner), 1986
Meot-Ner(Mautner), M.,
Comparative Stabilities of Cationic and Anionic Hydrogen-Bonded Networks. Mixed Clusters of Water-Methanol,
J. Am. Chem. Soc., 1986, 108, 20, 6189, https://doi.org/10.1021/ja00280a014
. [all data]
McIver, Scott, et al., 1973
McIver, R.T., Jr.; Scott, J.A.; Riveros, J.M.,
Effect of solvation on the intrinsic relative acidity of methanol and ethanol,
J. Am. Chem. Soc., 1973, 95, 2706. [all data]
Meot-Ner (Mautner), 1992
Meot-Ner (Mautner), M.,
Intermolecular Forces in Organic Clusters,
J. Am. Chem. Soc., 1992, 114, 9, 3312, https://doi.org/10.1021/ja00035a024
. [all data]
DeTuri and Ervin, 1999
DeTuri, V.F.; Ervin, K.M.,
Competitive threshold collision-induced dissociation: Gas-phase acidities and bond dissociation energies for a series of alcohols,
J. Phys. Chem. A, 1999, 103, 35, 6911-6920, https://doi.org/10.1021/jp991459m
. [all data]
Mackay, Rakshit, et al., 1982
Mackay, G.I.; Rakshit, A.B.; Bohme, D.K.,
An Experimental Study of the Reactivity and Relative Basicity of the Methoxide Anion in the Gas Phase at Room Temperature, and their Perturbation by Methanol Solvent,
Can. J. Chem., 1982, 60, 20, 2594, https://doi.org/10.1139/v82-373
. [all data]
Caldwell and Kebarle, 1986
Caldwell, G.; Kebarle, P.,
Mobility of Gaseous Ions in Weak Electric Fields
in Unpublished results, 1986. [all data]
Taft, 1983
Taft, R.W.,
Protonic acidities and basicities in the gas phase and in solution: Substiuent and solvent effects,
Prog. Phys. Org. Chem., 1983, 14, 247. [all data]
Ramond, Davico, et al., 2000
Ramond, T.M.; Davico, G.E.; Schwartz, R.L.; Lineberger, W.C.,
Vibronic structure of alkoxy radicals via photoelectron spectroscopy,
J. Chem. Phys., 2000, 112, 3, 1158-1169, https://doi.org/10.1063/1.480767
. [all data]
Haas and Harrison, 1993
Haas, M.J.; Harrison, A.G.,
The Fragmentation of Proton-Bound Cluster Ions and the Gas-Phase Acidities of Alcohols,
Int. J. Mass Spectrom. Ion Proc., 1993, 124, 2, 115, https://doi.org/10.1016/0168-1176(93)80003-W
. [all data]
Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr.,
The gas phase acidity scale from methanol to phenol,
J. Am. Chem. Soc., 1979, 101, 6047. [all data]
Chabinyc and Brauman, 1998
Chabinyc, M.L.; Brauman, J.I.,
Acidity, basicity, and the stability of hydrogen bonds: Complexes of RO-+HCF3,
J. Am. Chem. Soc., 1998, 120, 42, 10863-10870, https://doi.org/10.1021/ja9817592
. [all data]
Dang, Motell, et al., 1993
Dang, T.T.; Motell, E.L.; Travers, M.J.; Clifford, E.P.; Ellison, G.B.; Depuy, C.H.; Bierbaum, V.M.,
Experimental and Computational Studies of Deuterated Ethanols - Gas-Phase Acidities, Electron Affinities and Bond Dissociation Energies,
Int. J. Mass Spectrom. Ion Proc., 1993, 123, 3, 171, https://doi.org/10.1016/0168-1176(93)87096-B
. [all data]
Ellison, Engleking, et al., 1982
Ellison, G.B.; Engleking, P.C.; Lineberger, W.C.,
Photoelectron spectroscopy of alkoxide and enolate negative ions,
J. Phys. Chem., 1982, 86, 4873. [all data]
Williams and Hamill, 1968
Williams, J.M.; Hamill, W.H.,
Ionization potentials of molecules and free radicals and appearance potentials by electron impact in the mass spectrometer,
J. Chem. Phys., 1968, 49, 4467. [all data]
Trepka and Neuert, 1963
Trepka, L.v.; Neuert, H.,
Uber die Entstehenung von Negativen Ionen aus einigen Kohlenwasserstoffen und Alkoholen durch Elektronenstoss,
Z. Naturfor., 1963, 18A, 1295. [all data]
Page and Goode, 1969
Page, F.M.; Goode, G.C.,
Negative Ions and the Magnetron., Wiley, NY, 1969. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
EAneutral Electron affinity of neutral species 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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