Borane, trimethyl-
- Formula: C3H9B
- Molecular weight: 55.915
- IUPAC Standard InChIKey: WXRGABKACDFXMG-UHFFFAOYSA-N
- CAS Registry Number: 593-90-8
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: Trimethylborane; Trimethylboron; (CH3)3B
- Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Data at other public NIST sites:
- Options:
Data at NIST subscription sites:
NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.
Phase change data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR 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 as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Ttriple | 113.21 | K | N/A | Furukawa and Park, 1954 | Uncertainty assigned by TRC = 0.02 K; TRC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
3.25 | 113.2 | Domalski and Hearing, 1996 | AC |
Reaction thermochemistry data
Go To: Top, Phase change data, Gas phase ion energetics data, Ion clustering data, IR 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 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: F- + C3H9B = (F- • C3H9B)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 244.8 | kJ/mol | IMRB | Murphy and Beauchamp, 1977 | gas phase; MeSiF3>Me3B>SF4; B |
ΔrH° | 197. ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1985 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 100. | J/mol*K | N/A | Larson and McMahon, 1985 | gas phase; switching reaction,Thermochemical ladder(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 166. ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1985 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B,M |
C3H8B- + =
By formula: C3H8B- + H+ = C3H9B
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1532. ± 26. | kJ/mol | G+TS | Murphy and Beauchamp, 1976 | gas phase; Between AsH3,PH3; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1502. ± 25. | kJ/mol | IMRB | Murphy and Beauchamp, 1976 | gas phase; Between AsH3,PH3; value altered from reference due to change in acidity scale; B |
Gas phase ion energetics data
Go To: Top, Phase change data, Reaction thermochemistry data, Ion clustering data, IR 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 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
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.4 | PI | Holliday, Reade, et al., 1971 | LLK |
8.8 ± 0.2 | EI | Law and Margrave, 1956 | RDSH |
10.69 | PE | Berger, Kroner, et al., 1976 | Vertical value; LLK |
10.68 | PE | Barker, Lappert, et al., 1975 | Vertical value; LLK |
10.69 | PE | Fuss and Bock, 1974 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
B+ | 23.1 ± 0.3 | ? | EI | Law and Margrave, 1956 | RDSH |
CH3+ | 15.1 ± 0.3 | ? | EI | Law and Margrave, 1956 | RDSH |
CH3B+ | 17.0 ± 0.5 | ? | EI | Law and Margrave, 1956 | RDSH |
C2H6B+ | 10.3 ± 0.2 | CH3 | EI | Law and Margrave, 1956 | RDSH |
De-protonation reactions
C3H8B- + =
By formula: C3H8B- + H+ = C3H9B
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1532. ± 26. | kJ/mol | G+TS | Murphy and Beauchamp, 1976 | gas phase; Between AsH3,PH3; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1502. ± 25. | kJ/mol | IMRB | Murphy and Beauchamp, 1976 | gas phase; Between AsH3,PH3; value altered from reference due to change in acidity scale; B |
Ion clustering data
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR 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 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: F- + C3H9B = (F- • C3H9B)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 244.8 | kJ/mol | IMRB | Murphy and Beauchamp, 1977 | gas phase; MeSiF3>Me3B>SF4; B |
ΔrH° | 197. ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1985 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 100. | J/mol*K | N/A | Larson and McMahon, 1985 | gas phase; switching reaction,Thermochemical ladder(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 166. ± 8.4 | kJ/mol | IMRE | Larson and McMahon, 1985 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B,M |
IR Spectrum
Go To: Top, Phase change data, 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 by: Coblentz Society, Inc.
Gas Phase Spectrum
Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.
Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.
Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.
Additional Data
View scan of original (hardcopy) spectrum.
View image of digitized spectrum (can be printed in landscape orientation).
View spectrum image in SVG format.
Download spectrum in JCAMP-DX format.
Owner | COBLENTZ SOCIETY Collection (C) 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | KALLERY CHEMICAL COMPANY |
Source reference | COBLENTZ NO. 832 |
Date | 1960 |
State | VAPOR AT 30 mmHg PRESSURE; $$ RESEARCH PURITY |
Instrument | Not specified, most likely a prism, grating, or hybrid spectrometer. |
Path length | 10 CM |
Resolution | 4 |
Sampling procedure | TRANSMISSION |
Data processing | DIGITIZED BY NIST FROM HARD COPY |
References
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Furukawa and Park, 1954
Furukawa, G.T.; Park, R.P.,
Heat Capacity, Heats of Fusion, Transition, and Vaporization, and Vapor Pressure of Trimethylborane B(CH3)3, Natl. Bur. Stand., 1954. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [all data]
Murphy and Beauchamp, 1977
Murphy, M.K.; Beauchamp, J.L.,
Fluorine and Alkyl Substituent Effects on Gas-Phase Lewis Acidities of Boranes by ICR Spectroscopy,
Inorg. Chem., 1977, 16, 2437. [all data]
Larson and McMahon, 1985
Larson, J.W.; McMahon, T.B.,
Fluoride and chloride affinities of the main group oxides, fluorides, oxofluorides, and alkyls. Quantitative scales of lewis acidities from ICR halide exchange equilibria,
J. Am. Chem. Soc., 1985, 107, 766. [all data]
Wenthold and Squires, 1995
Wenthold, P.G.; Squires, R.R.,
Bond dissociation energies of F2(-) and HF2(-). A gas-phase experimental and G2 theoretical study,
J. Phys. Chem., 1995, 99, 7, 2002, https://doi.org/10.1021/j100007a034
. [all data]
Arshadi, Yamdagni, et al., 1970
Arshadi, M.; Yamdagni, R.; Kebarle, P.,
Hydration of Halide Negative Ions in the Gas Phase. II. Comparison of Hydration Energies for the Alkali Positive and Halide Negative Ions,
J. Phys. Chem., 1970, 74, 7, 1475, https://doi.org/10.1021/j100702a014
. [all data]
Murphy and Beauchamp, 1976
Murphy, M.K.; Beauchamp, J.L.,
Acid-base properties and gas-phase ion chemistry of (CH3)3B,
J. Am. Chem. Soc., 1976, 98, 1433. [all data]
Holliday, Reade, et al., 1971
Holliday, A.K.; Reade, W.; Johnstone, R.A.W.; Neville, A.F.,
Photo-electron spectrum of trivinylboron,
Chem. Commun., 1971, 51. [all data]
Law and Margrave, 1956
Law, R.W.; Margrave, J.L.,
Mass spectrometer appearance potentials for positive ion fragments from BF3, B(CH3)3, B(C2H5)3, B(OCH3)3, and HB(OCH3)2,
J. Chem. Phys., 1956, 25, 1086. [all data]
Berger, Kroner, et al., 1976
Berger, H.-O.; Kroner, J.; Noth, H.,
Die borhalogen-bindung in Methylhalogenboranen: Photoelektronenspektren und ab initio-Rechnungen,
Chem. Ber., 1976, 109, 2266. [all data]
Barker, Lappert, et al., 1975
Barker, G.K.; Lappert, M.F.; Pedley, J.B.; Sharp, G.J.; Westwood, N.P.C.,
Bonding studies of boron and the group 3-5 elements. Part XV. He(I) photoelectron spectra of monomeric group 3 tri-halide, trimethyl, and mixed halogenomethyl species,
J. Chem. Soc. Dalton Trans., 1975, 1765. [all data]
Fuss and Bock, 1974
Fuss, W.; Bock, H.,
Photoelectron spectra and molecular properties. XXXVI. (H3C)3B, (H3C)2BF, (H3C)2BN(CH3)2, and (H3C)2CC(CH3)2: The use of ionization potentials in assigning UV spectra,
J. Chem. Phys., 1974, 61, 1613. [all data]
Notes
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, References
- Symbols used in this document:
AE Appearance energy Ttriple Triple point temperature 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 - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
- The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
- Customer support for NIST Standard Reference Data products.