Propane, 2-bromo-2-methyl-
- Formula: C4H9Br
- Molecular weight: 137.018
- IUPAC Standard InChIKey: RKSOPLXZQNSWAS-UHFFFAOYSA-N
- CAS Registry Number: 507-19-7
- 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: tert-Butyl bromide; Trimethylbromomethane; 2-Bromo-2-methylpropane; 2-Bromoisobutane; tert-C4H9Br; t-Butyl bromide; Bromotrimethylmethane; Tertiarybutyl bromide; Butylbromide, tert-; 1,1-Dimethylethyl bromide; 2-Methyl-2-bromopropane; NSC 8418
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Gas phase thermochemistry 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -132.4 ± 1.5 | kJ/mol | Eqk | Howlett, 1957 | Reanalyzed by Cox and Pilcher, 1970, Original value = -127.5 kJ/mol |
Reaction thermochemistry 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
RCD - Robert C. Dunbar
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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- + C4H9Br = (Br- • C4H9Br)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 65.3 ± 4.2 | kJ/mol | TDAs | Li, Ross, et al., 1996 | gas phase; B |
ΔrH° | 51.88 | kJ/mol | TDAs | Dougherty, 1974 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 80.8 | J/mol*K | HPMS | Dougherty, 1974 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 30.5 ± 0.84 | kJ/mol | TDAs | Li, Ross, et al., 1996 | gas phase; B |
ΔrG° | 28.0 | kJ/mol | TDAs | Dougherty, 1974 | gas phase; B |
By formula: F- + C4H9Br = (F- • C4H9Br)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 93.3 ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1983 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 64.0 ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1983 | gas phase; B |
By formula: Cl- + C4H9Br = (Cl- • C4H9Br)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 74.1 ± 4.2 | kJ/mol | TDAs | Li, Ross, et al., 1996 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 37.2 ± 0.84 | kJ/mol | TDAs | Li, Ross, et al., 1996 | gas phase; B |
By formula: Na+ + C4H9Br = (Na+ • C4H9Br)
Free energy of reaction
ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
57.3 | 298. | IMRE | McMahon and Ohanessian, 2000 | Anchor alanine=39.89; RCD |
By formula: C4H9Br = C4H8 + HCl
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 79. ± 4. | kJ/mol | Eqk | Kistiakowsky and Stauffer, 1937 | gas phase; ALS |
By formula: HBr + C4H8 = C4H9Br
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -78.868 | kJ/mol | Eqk | Howlett, 1957 | gas phase; ALS |
By formula: C4H9Br = C4H9Br
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 19.0 | kJ/mol | Eqk | Nesterova and Rozhnov, 1974 | gas phase; ALS |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, 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 evaluated as indicated in comments:
L - Sharon G. Lias
Data compiled as indicated in comments:
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.92 ± 0.03 | eV | N/A | N/A | L |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.95 | EST | Luo and Pacey, 1992 | LL |
9.95 ± 0.015 | PE | Hashmall and Heilbronner, 1970 | RDSH |
9.89 ± 0.03 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
9.95 | PE | Kimura, Katsumata, et al., 1981 | Vertical value; LLK |
10.05 | PE | Flamini, Semprini, et al., 1976 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C4H9+ | 9.85 ± 0.01 | Br | PI | McLoughlin and Traeger, 1979 | LLK |
References
Go To: Top, Gas phase thermochemistry data, 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.
Howlett, 1957
Howlett, K.E.,
The use of equilibrium constants to calculate thermodynamic quantities. Part III. Equilibria in the system tert.-butyl bromideisobutene-hydrogen bromide,
J. Chem. Soc., 1957, 2834-2836. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Li, Ross, et al., 1996
Li, C.; Ross, P.; Szulejko, J.; McMahon, T.B.,
High-Pressure Mass Spectrometric Investigations of the Potential Energy Surfaces of Gas-Phase Sn2 Reactions.,
J. Am. Chem. Soc., 1996, 118, 39, 9360, https://doi.org/10.1021/ja960565o
. [all data]
Dougherty, 1974
Dougherty, R.C.,
SN2 reactions in the gas phase. Alkyl group structural effects,
Org. Mass Spectrom., 1974, 8, 85. [all data]
Larson and McMahon, 1983
Larson, J.W.; McMahon, T.B.,
Strong hydrogen bonding in gas-phase anions. An ion cyclotron resonance determination of fluoride binding energetics to bronsted acids from gas-phase fluoride exchange equilibria measurements,
J. Am. Chem. Soc., 1983, 105, 2944. [all data]
McMahon and Ohanessian, 2000
McMahon, T.B.; Ohanessian, G.,
An Experimental and Ab Initio Study of the Nature of the Binding in Gas-Phase Complexes of Sodium Ions,
Chem. Eur. J., 2000, 6, 16, 2931, https://doi.org/10.1002/1521-3765(20000818)6:16<2931::AID-CHEM2931>3.0.CO;2-7
. [all data]
Kistiakowsky and Stauffer, 1937
Kistiakowsky, G.B.; Stauffer, C.H.,
The kinetics of gaseous addition of halogen acids to isobutene, 1937, 165-170. [all data]
Nesterova and Rozhnov, 1974
Nesterova, T.N.; Rozhnov, A.M.,
Isomerization of isostructural monobromobutanes,
Izv. Vyssh. Uchebn. Zaved., Khim. Khim. Tekhnol., 1974, 17, 556-558. [all data]
Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D.,
Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes,
Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]
Hashmall and Heilbronner, 1970
Hashmall, J.A.; Heilbronner, E.,
n-Ionization potentials of alkyl bromides,
Angew. Chem. Intern. Ed., 1970, 9, 305. [all data]
Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J.,
Ionization potentials of some molecules,
J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [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]
Flamini, Semprini, et al., 1976
Flamini, A.; Semprini, E.; Stefani, F.; Sorriso, S.; Cardaci, G.,
He(I) photoelectron spectra and semiempirical molecular-orbital calculations on methylmetal halides of group 4A elements,
J. Chem. Soc. Dalton Trans., 1976, 731. [all data]
McLoughlin and Traeger, 1979
McLoughlin, R.G.; Traeger, J.C.,
Heat of formation for tert-butyl cation in the gas phase,
J. Am. Chem. Soc., 1979, 101, 5791. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy T Temperature ΔfH°gas Enthalpy of formation of gas at standard conditions 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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