Formamide, N-methyl-

• Formula: C₂H₅NO
• Molecular weight: 59.0672
• IUPAC Standard InChI: InChI=1S/C2H5NO/c1-3-2-4/h2H,1H3,(H,3,4) Copy

  
• IUPAC Standard InChIKey: ATHHXGZTWNVVOU-UHFFFAOYSA-N Copy
• CAS Registry Number: 123-39-7
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  View 3d structure (requires JavaScript / HTML 5)
• Other names: Methylformamide; Monomethylformamide; N-Methylformamide; HCONHCH3; EK 7011; NSC 3051; X 188; N-Monomethylformamide
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • UV/Visible spectrum
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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.

Ion clustering data

Go To: Top, Mass spectrum (electron ionization), Gas Chromatography, 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:
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

C₂H₄NO^- +  = (C₂H₄NO^- • )

By formula: C₂H₄NO^- + C₂H₅NO = (C₂H₄NO^- • C₂H₅NO)

 +  = ( • )

By formula: C₄H₄N^- + C₂H₅NO = (C₄H₄N^- • C₂H₅NO)

 +  = ( • )

By formula: Li⁺ + C₂H₅NO = (Li⁺ • C₂H₅NO)

Free energy of reaction

Mass spectrum (electron ionization)

Go To: Top, Ion clustering data, Gas Chromatography, 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

Gas Chromatography

Go To: Top, Ion clustering data, Mass spectrum (electron ionization), 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Kovats' RI, non-polar column, isothermal

View large format table.

Normal alkane RI, non-polar column, temperature ramp

View large format table.

Normal alkane RI, polar column, custom temperature program

View large format table.

References

Go To: Top, Ion clustering data, Mass spectrum (electron ionization), Gas Chromatography, Notes

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

Meot-Ner (Mautner), 1988
Meot-Ner (Mautner), M., Models for Strong Interactions in Proteins and Enzymes. 2. Interactions of Ions with the Peptide Link and Imidazole, J. Am. Chem. Soc., 1988, 110, 10, 3075, https://doi.org/10.1021/ja00218a014 . [all data]

Herreros, Gal, et al., 1999
Herreros, M.; Gal, J.-F.; Maria, P.-C.; Decouzon, M., Gas-Phase Basicity of Simple Amides Toward Proton and Lithium Cation: An Experimental and Theoretical Study, Eur. J. Mass Spectrom., 1999, 5, 1, 259, https://doi.org/10.1255/ejms.282 . [all data]

Krawczyk and Piotrowski, 1989
Krawczyk, W.; Piotrowski, G.T., Relationships Between Structure and Retention Index for N-Substituted Amides of Aliphatic Acids on a Non-Polar Column, J. Chromatogr., 1989, 463, 297-304, https://doi.org/10.1016/S0021-9673(01)84484-8 . [all data]

Zenkevich, 2005
Zenkevich, I.G., Experimentally measured retention indices., 2005. [all data]

Peng, Yang, et al., 1991
Peng, C.T.; Yang, Z.C.; Ding, S.F., Prediction of rentention idexes. II. Structure-retention index relationship on polar columns, J. Chromatogr., 1991, 586, 1, 85-112, https://doi.org/10.1016/0021-9673(91)80028-F . [all data]

Notes

Go To: Top, Ion clustering data, Mass spectrum (electron ionization), Gas Chromatography, References

• Symbols used in this document:
  

  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
• 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.

© 2026 by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Copyright for NIST Standard Reference Data is governed by the Standard Reference Data Act.