Dimethylamine

• Formula: C₂H₇N
• Molecular weight: 45.0837
• IUPAC Standard InChI: InChI=1S/C2H7N/c1-3-2/h3H,1-2H3 Copy

  
• IUPAC Standard InChIKey: ROSDSFDQCJNGOL-UHFFFAOYSA-N Copy
• CAS Registry Number: 124-40-3
• 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: Methanamine, N-methyl-; (CH3)2NH; N-Methylmethanamine; Rcra waste number U092; UN 1032; N,N-Dimethylamine; NSC 8650
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
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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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.

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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
RCD - Robert C. Dunbar

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

C₃H₉Sn⁺ +  = (C₃H₉Sn⁺ • )

By formula: C₃H₉Sn⁺ + C₂H₇N = (C₃H₉Sn⁺ • C₂H₇N)

Free energy of reaction

 +  = ( • )

By formula: Li⁺ + C₂H₇N = (Li⁺ • C₂H₇N)

C₂H₆N^- +  =

By formula: C₂H₆N^- + H⁺ = C₂H₇N

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

By formula: C₃H₉Si⁺ + C₂H₇N = (C₃H₉Si⁺ • C₂H₇N)

C₂H₈N⁺ +  = (C₂H₈N⁺ • )

By formula: C₂H₈N⁺ + C₂H₇N = (C₂H₈N⁺ • C₂H₇N)

(C₂H₈N⁺ • 2) +  = (C₂H₈N⁺ • 3)

By formula: (C₂H₈N⁺ • 2C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 3C₂H₇N)

(C₂H₈N⁺ • 3) +  = (C₂H₈N⁺ • 4)

By formula: (C₂H₈N⁺ • 3C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 4C₂H₇N)

(C₂H₈N⁺ • 4) +  = (C₂H₈N⁺ • 5)

By formula: (C₂H₈N⁺ • 4C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 5C₂H₇N)

(C₂H₈N⁺ • ) +  = (C₂H₈N⁺ • 2)

By formula: (C₂H₈N⁺ • C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 2C₂H₇N)

C₃H₁₀N⁺ +  = (C₃H₁₀N⁺ • )

By formula: C₃H₁₀N⁺ + C₂H₇N = (C₃H₁₀N⁺ • C₂H₇N)

 +  = ( • )

By formula: K⁺ + C₂H₇N = (K⁺ • C₂H₇N)

=  + 

By formula: C₃H₉NO = C₂H₇N + CH₂O

 +  = ( • )

By formula: Na⁺ + C₂H₇N = (Na⁺ • C₂H₇N)

Free energy of reaction

=  + 

By formula: C₉H₁₁ClN₂O = C₇H₄ClNO + C₂H₇N

=  + 

By formula: C₁₀H₁₄N₂O = C₂H₇N + C₈H₇NO

=  + 

By formula: C₁₀H₁₄N₂O₂ = C₂H₇N + C₈H₇NO₂

=  + 

By formula: C₉H₁₁ClN₂O = C₂H₇N + C₇H₄ClNO

=  + 

By formula: C₁₀H₁₁F₃N₂O = C₂H₇N + C₈H₄F₃NO

=  + 

By formula: C₉H₁₀Cl₂N₂O = C₇H₃Cl₂NO + C₂H₇N

 + 2 =  + 

By formula: C₃H₅Cl + 2C₂H₇N = C₅H₁₁N + C₂H₈ClN

=  + 

By formula: C₁₀H₁₄N₂O = C₂H₇N + C₈H₇NO

2 +  =  + 

By formula: 2C₂H₇N + CH₂O = C₅H₁₄N₂ + H₂O

=  + 

By formula: C₉H₁₂N₂O = C₇H₅NO + C₂H₇N

 +  =

By formula: C₂H₇N + CH₂O = C₃H₉NO

2 =  + 

By formula: 2CH₅N = C₂H₇N + H₃N

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
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 C₂H₇N⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₂H₆N^- +  =

By formula: C₂H₆N^- + H⁺ = C₂H₇N

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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar

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

C₂H₈N⁺ +  = (C₂H₈N⁺ • )

By formula: C₂H₈N⁺ + C₂H₇N = (C₂H₈N⁺ • C₂H₇N)

(C₂H₈N⁺ • ) +  = (C₂H₈N⁺ • 2)

By formula: (C₂H₈N⁺ • C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 2C₂H₇N)

(C₂H₈N⁺ • 2) +  = (C₂H₈N⁺ • 3)

By formula: (C₂H₈N⁺ • 2C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 3C₂H₇N)

(C₂H₈N⁺ • 3) +  = (C₂H₈N⁺ • 4)

By formula: (C₂H₈N⁺ • 3C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 4C₂H₇N)

(C₂H₈N⁺ • 4) +  = (C₂H₈N⁺ • 5)

By formula: (C₂H₈N⁺ • 4C₂H₇N) + C₂H₇N = (C₂H₈N⁺ • 5C₂H₇N)

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

By formula: C₃H₉Si⁺ + C₂H₇N = (C₃H₉Si⁺ • C₂H₇N)

C₃H₉Sn⁺ +  = (C₃H₉Sn⁺ • )

By formula: C₃H₉Sn⁺ + C₂H₇N = (C₃H₉Sn⁺ • C₂H₇N)

Free energy of reaction

C₃H₁₀N⁺ +  = (C₃H₁₀N⁺ • )

By formula: C₃H₁₀N⁺ + C₂H₇N = (C₃H₁₀N⁺ • C₂H₇N)

 +  = ( • )

By formula: K⁺ + C₂H₇N = (K⁺ • C₂H₇N)

 +  = ( • )

By formula: Li⁺ + C₂H₇N = (Li⁺ • C₂H₇N)

 +  = ( • )

By formula: Na⁺ + C₂H₇N = (Na⁺ • C₂H₇N)

Free energy of reaction

Gas Chromatography

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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

Kovats' RI, non-polar column, isothermal

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Kovats' RI, polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Gas Chromatography, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Issoire and Long, 1960
Issoire, J.; Long, C., Etude de la thermodynamique chimique de la reaction de formation des methylamines, Bull. Soc. Chim. France, 1960, 2004-2012. [all data]

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Stone and Splinter, 1984
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Dzidic, I.; Kebarle, P., Hydration of the Alkali Ions in the Gas Phase. Enthalpies and Entropies of Reactions M+(H2O)n-1 + H2O = M+(H2O)n, J. Phys. Chem., 1970, 74, 7, 1466, https://doi.org/10.1021/j100702a013 . [all data]

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Radisic, D.; Xu, S.J.; Bowen, K.H., Photoelectron spectroscopy of the anions, CH3NH- and (CH3)(2)N- and the anion complexes, H-(CH3NH2) and (CH3)(2)N-[(CH3)(2)NH), Chem. Phys. Lett., 2002, 354, 1-2, 9-13, https://doi.org/10.1016/S0009-2614(01)01470-1 . [all data]

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MacKay, G.J.; Hemsworth, R.S.; Bohme, D.K., Absolute gas-phase acidities of CH₃NH₂, C₂H₅NH₂, (CH₃)₂NH, and (CH₃)₃N, Can. J. Chem., 1976, 54, 1624. [all data]

Li and Stone, 1990
Li, X.; Stone, A.J., Gas-Phase (CH3)3Si+ Affinities of Alkylamines and Proton Affinities of Trimethylsilyl Alkylamines, Int. J. Mass Spectrom. Ion Proc., 1990, 101, 2-3, 149, https://doi.org/10.1016/0168-1176(90)87008-5 . [all data]

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Yamdagni and Kebarle, 1973
Yamdagni, R.; Kebarle, P., Gas - Phase Basicites of Amines. Hydrogen Bonding in Proton - Bound Amine Dimers and Proton - Induced Cyclization of alpha, omega - Diamines, J. Am. Chem. Soc., 1973, 95, 11, 3504, https://doi.org/10.1021/ja00792a010 . [all data]

Davidson and Kebarle, 1976
Davidson, W.R.; Kebarle, P., Binding Energies and Stabilities of Potassium Ion Complexes from Studies of Gas Phase Ion Equilibria K+ + M = K+.M, J. Am. Chem. Soc., 1976, 98, 20, 6133, https://doi.org/10.1021/ja00436a011 . [all data]

Rogers and Rapiejko, 1974
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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]

Chimishkyan, Svetlova, et al., 1984
Chimishkyan, A.L.; Svetlova, L.P.; Leonova, T.V.; Gluyaev, N.D., Thermal decomposition of substituted ureas, J. Gen. Chem. USSR, 1984, 54, 1317-1320. [all data]

Beldie, Aelenei, et al., 1982
Beldie, C.; Aelenei, N.; Onu, A.; Nemtoi, G., Thermochemical characterization of the reactions involved in the allyldimethylamine synthesis, Rev. Chim. (Bucharest), 1982, 33, 917-919. [all data]

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]

Aue, Webb, et al., 1980
Aue, D.H.; Webb, H.M.; Davidson, W.R.; Vidal, M.; Bowers, M.T.; Goldwhite, H.; Vertal, L.E.; Douglas, J.E.; Kollman, P.A.; Kenyon, G.L., Proton affinities photoelectron spectra of three-membered-ring J. Heterocycl. Chem., J. Am. Chem. Soc., 1980, 102, 5151. [all data]

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Baldwin, Loudon, et al., 1977
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Aue, Webb, et al., 1976
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Vovna, V.I.; Vilesov, F.I., Photoelectron spectra the structure of molecular orbitals of methyl amines, Opt. Spectrosc., 1974, 36, 251. [all data]

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Maier, J.P.; Turner, D.W., Steric inhibition of resonance studied by molecular photoelectron spectroscopy Part 3. Anilines, Phenols and Related Compounds, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 521. [all data]

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Cornford, Frost, et al., 1971
Cornford, A.B.; Frost, D.C.; Herring, F.G.; McDowell, C.A., Electronic levels of methyl amines by photoelectron spectroscopy and an i.n.d.o. calculation, Can. J. Chem., 1971, 49, 1135. [all data]

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Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Gas Chromatography, 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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