1,3-Diazine

• Formula: C₄H₄N₂
• Molecular weight: 80.0880
• IUPAC Standard InChI: InChI=1S/C4H4N2/c1-2-5-4-6-3-1/h1-4H Copy

  
• IUPAC Standard InChIKey: CZPWVGJYEJSRLH-UHFFFAOYSA-N Copy
• CAS Registry Number: 289-95-2
• 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: Pyrimidine; m-Diazine; Metadiazine; Miazine; 1,3-Diazabenzene; Py; Pyr
• 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
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Ion clustering data
  • IR Spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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

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:
MS - José A. Martinho Simões
B - John E. Bartmess
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

C₁₀H₅CrNO₅ (solution) +  (solution) =  (solution) +  (solution)

By formula: C₁₀H₅CrNO₅ (solution) + CO (solution) = C₆CrO₆ (solution) + C₄H₄N₂ (solution)

 (cr) +  (l) = C₁₀H₅NO₅W (cr) +  (g)

By formula: C₆O₆W (cr) + C₄H₄N₂ (l) = C₁₀H₅NO₅W (cr) + CO (g)

C₄H₃N₂^- +  =

By formula: C₄H₃N₂^- + H⁺ = C₄H₄N₂

 (solution) +  (solution) = C₁₀H₅NO₅W (solution) +  (solution)

By formula: C₆O₆W (solution) + C₄H₄N₂ (solution) = C₁₀H₅NO₅W (solution) + CO (solution)

C₃₉H₆₈O₃P₂W (solution) +  (solution) = C₄₄H₇₁NO₃P₂W (solution) +  (g)

By formula: C₃₉H₆₈O₃P₂W (solution) + C₄H₄N₂ (solution) = C₄₄H₇₁NO₃P₂W (solution) + H₂ (g)

C₁₄H₁₀CrN₂O₄ (cr) = 2 (g) + 4 (g) +  (cr)

By formula: C₁₄H₁₀CrN₂O₄ (cr) = 2C₄H₄N₂ (g) + 4CO (g) + Cr (cr)

C₈H₆MoO₃ (solution) + 3 (solution) = C₁₈H₁₅MoN₃O₃ (solution) +  (solution)

By formula: C₈H₆MoO₃ (solution) + 3C₄H₄N₂ (solution) = C₁₈H₁₅MoN₃O₃ (solution) + C₅H₆ (solution)

 +  = C₄H₄N₃O^-

By formula: NO^- + C₄H₄N₂ = C₄H₄N₃O^-

C₉H₉CrN₃O₃ (solution) + 3 (solution) = C₁₈H₁₅CrN₃O₃ (solution) + 3 (solution)

By formula: C₉H₉CrN₃O₃ (solution) + 3C₄H₄N₂ (solution) = C₁₈H₁₅CrN₃O₃ (solution) + 3C₂H₃N (solution)

C₇H₉Cl₂NPd (solution) +  (l) = (PdCl₂(C₅H₅N)₂) (solution) +  (solution)

By formula: C₇H₉Cl₂NPd (solution) + C₄H₄N₂ (l) = (PdCl₂(C₅H₅N)₂) (solution) + C₂H₄ (solution)

C₁₀H₅NO₅W (cr) +  (g) =  (g) +  (g)

By formula: C₁₀H₅NO₅W (cr) + CO (g) = C₆O₆W (g) + C₄H₄N₂ (g)

C₁₂H₁₆CrO₅ (solution) +  (solution) =  (solution) + C₁₀H₅CrNO₅ (solution)

By formula: C₁₂H₁₆CrO₅ (solution) + C₄H₄N₂ (solution) = C₇H₁₆ (solution) + C₁₀H₅CrNO₅ (solution)

C₃₉H₆₆MoO₃P₃ (solution) +  (solution) = C₄₄H₇₁MoNO₃P₂ (solution)

By formula: C₃₉H₆₆MoO₃P₃ (solution) + C₄H₄N₂ (solution) = C₄₄H₇₁MoNO₃P₂ (solution)

 (cr) + 3 (g) = C₁₈H₁₅MoN₃O₃ (cr) + 3 (g)

By formula: C₆MoO₆ (cr) + 3C₄H₄N₂ (g) = C₁₈H₁₅MoN₃O₃ (cr) + 3CO (g)

 (cr) + 3 (g) = C₁₈H₁₅N₃O₃W (g) + 3 (g)

By formula: C₆O₆W (cr) + 3C₄H₄N₂ (g) = C₁₈H₁₅N₃O₃W (g) + 3CO (g)

C₁₀H₅CrNO₅ (cr) +  (g) =  (g) +  (g)

By formula: C₁₀H₅CrNO₅ (cr) + CO (g) = C₆CrO₆ (g) + C₄H₄N₂ (g)

C₁₀H₅MoNO₅ (cr) +  (g) =  (g) +  (g)

By formula: C₁₀H₅MoNO₅ (cr) + CO (g) = C₆MoO₆ (g) + C₄H₄N₂ (g)

 +  = ( • )

By formula: Fe⁺ + C₄H₄N₂ = (Fe⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Cr⁺ + C₄H₄N₂ = (Cr⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Ti⁺ + C₄H₄N₂ = (Ti⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Mn⁺ + C₄H₄N₂ = (Mn⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Sc⁺ + C₄H₄N₂ = (Sc⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Mg⁺ + C₄H₄N₂ = (Mg⁺ • C₄H₄N₂)

 +  = ( • )

By formula: V⁺ + C₄H₄N₂ = (V⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Ni⁺ + C₄H₄N₂ = (Ni⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Al⁺ + C₄H₄N₂ = (Al⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Zn⁺ + C₄H₄N₂ = (Zn⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Co⁺ + C₄H₄N₂ = (Co⁺ • C₄H₄N₂)

 +  = ( • )

By formula: Cu⁺ + C₄H₄N₂ = (Cu⁺ • C₄H₄N₂)

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
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
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 C₄H₄N₂⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₄H₃N₂^- +  =

By formula: C₄H₃N₂^- + H⁺ = C₄H₄N₂

Mass spectrum (electron ionization)

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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

Spectrum

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Additional Data

UV/Visible spectrum

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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: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, Notes

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

Nabavian, Sabbah, et al., 1977
Nabavian, P.M.; Sabbah, R.; Chastel, R.; Laffitte, M., Thermodynamique de composes azotes. II. Etude thermochimique des acides aminobenzoiques, de la pyrimidine, de l'uracile et de la thymine., J. Chim. Phys., 1977, 74, 115-126. [all data]

Pedley, Naylor, et al., 1986
Pedley, J.B.; Naylor, R.D.; Kirby, S.P., Thermochemical Data of Organic Compounds, Chapman and Hall, New York, 1986, 1-792. [all data]

Tjebbes, 1962
Tjebbes, J., The heats of combustion and formation of the three diazines and their resonance energies, Acta Chem. Scand., 1962, 16, 916-921. [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]

Wovkulich and Atwood, 1980
Wovkulich, M.J.; Atwood, J.D., J. Organometal. Chem., 1980, 184, 77. [all data]

Dennenberg and Darensbourg, 1972
Dennenberg, R.J.; Darensbourg, D.J., Inorg. Chem., 1972, 11, 72. [all data]

Graham and Angelici, 1967
Graham, J.R.; Angelici, R.J., Inorg. Chem., 1967, 6, 2082. [all data]

Nakashima and Adamson, 1982
Nakashima, M.; Adamson, A.W., J. Phys. Chem., 1982, 86, 2905. [all data]

Meot-ner and Kafafi, 1988
Meot-ner, M.; Kafafi, S.A., Carbon Acidities of Aromatic Compounds, J. Am. Chem. Soc., 1988, 110, 19, 6297, https://doi.org/10.1021/ja00227a003 . [all data]

Wren, Vogelhuber, et al., 2012
Wren, S.W.; Vogelhuber, K.M.; Garver, J.M.; Kato, S.; Sheps, L.; Bierbaum, V.M.; Lineberger, W.C., C-H Bond Strengths and Acidities in Aromatic Systems: Effects of Nitrogen Incorporation in Mono-, Di-, and Triazines, J. Am. Chem. Soc., 2012, 134, 15, 6584-6595, https://doi.org/10.1021/ja209566q . [all data]

Gonzalez, Zhang, et al., 1988
Gonzalez, A.A.; Zhang, K.; Nolan, S.P.; Lopez de la Vega, R.; Mukerjee, S.L.; Hoff, C.D., Organometallics, 1988, 7, 2429. [all data]

Adedeji, Connor, et al., 1978
Adedeji, F.A.; Connor, J.A.; Demain, C.P.; Martinho Simões, J.A.; Skinner, H.A.; Zafarani- Moattar, M.T., J. Organometal. Chem., 1978, 149, 333. [all data]

Nolan, Hoff, et al., 1985
Nolan, S.P.; Hoff, C.D.; Landrum, J.T., J. Organometal. Chem., 1985, 282, 357. [all data]

Le Barbu, Schiedt, et al., 2002
Le Barbu, K.; Schiedt, J.; Weinkauf, R.; Schlag, E.W.; Nilles, J.M.; Xu, S.J.; Thomas, O.C.; Bowen, K.H., Microsolvation of small anions by aromatic molecules: An exploratory study, J. Chem. Phys., 2002, 116, 22, 9663-9671, https://doi.org/10.1063/1.1475750 . [all data]

Mukerjee, Lang, et al., 1992
Mukerjee, S.L.; Lang, R.F.; Ju, T.; Kiss, G.; Hoff, C.D.; Nolan, S.P., Inorg. Chem., 1992, 31, 4885. [all data]

Partenheimer and Durham, 1974
Partenheimer, W.; Durham, B., J. Am. Chem. Soc., 1974, 96, 3800. [all data]

Daamen, van der Poel, et al., 1979
Daamen, H.; van der Poel, H.; Stufkens, D.J.; Oskam, A., Thermochim. Acta, 1979, 34, 69. [all data]

Meester, Vriends, et al., 1976
Meester, M.A.M.; Vriends, R.C.J.; Stufkens, D.J.; Vrieze, K., Inorg. Chim. Acta, 1976, 19, 95. [all data]

Yang, Vaida, et al., 1988
Yang, G.K.; Vaida, V.; Peters, K.S., Polyhedron, 1988, 7, 1619. [all data]

Zhang, Gonzalez, et al., 1991
Zhang, K.; Gonzalez, A.A.; Murkerjee, S.L.; Chou, S.-J.; Hoff, C.D.; Kubat- Martin, K.A.; Barnhart, D.; Kubas, G.J., J. Am. Chem. Soc., 1991, 113, 9170. [all data]

Amunugama and Rodgers, 2001
Amunugama, R.; Rodgers, M.T., Periodic Trends in the Binding of Metal Ions to Pyrimidine Studied by Threshold Collision-Induced Dissociation and Density Functional Theory, J. Phys. Chem. A, 2001, 105, 43, 9883, https://doi.org/10.1021/jp010663i . [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]

Nenner and Schultz, 1975
Nenner, I.; Schultz, G.J., Temporary negative ions and electron affinities of benzene and N-heterocyclic molecules: Pyridine, pyridazine, pyrimidine, pyrazine, and s-triazine, J. Chem. Phys., 1975, 62, 1747. [all data]

Piancastelli, Keller, et al., 1983
Piancastelli, M.N.; Keller, P.R.; Taylor, J.W.; Grimm, F.A.; Carlson, T.A., Angular distribution parameter as a function of photon energy for some mono- and diazabenzenes and its use for orbital assignment, J. Am. Chem. Soc., 1983, 105, 4235. [all data]

Gleiter, Heilbronner, et al., 1972
Gleiter, R.; Heilbronner, E.; Hornung, V., Photoelectron spectra of azabenzenes azanaphthalenes: I. Pyridine, diazines s-triazine and s-tetrazine, Helv. Chim. Acta, 1972, 55, 255. [all data]

Asbrink, Fridh, et al., 1972
Asbrink, L.; Fridh, C.; Jonsson, B.O.; Lindholm, E., Rydberg series in small molecules. XVI. Photoelectron, UV, mass and electron impact spectra of pyrimidine, Int. J. Mass Spectrom. Ion Phys., 1972, 8, 215. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. II.The ionization potentials of azabenzenes and azanaphthalenes, J. Chem. Phys., 1969, 51, 263. [all data]

Yencha and El-Sayed, 1968
Yencha, A.J.; El-Sayed, M.A., Lowest ionization potentials of some nitrogen heterocyclics, J. Chem. Phys., 1968, 48, 3469. [all data]

Hush and Cheung, 1975
Hush, N.S.; Cheung, A.S., Ionization potentials and donor properties of nucleic acid bases and related compounds, Chem. Phys. Lett., 1975, 34, 11. [all data]

Suffolk, 1974
Suffolk, R.J., The photoelectron spectra of the perfluorodiazines, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 53. [all data]

Gleiter, Heilbronner, et al., 1970
Gleiter, R.; Heilbronner, E.; Hornung, V., Lone pair interaction in pyridazine, pyrimidine, and pyrazine, Angew. Chem. Int. Ed. Engl., 1970, 9, 901. [all data]

Momigny, Urbain, et al., 1965
Momigny, J.; Urbain, J.; Wankenne, H., Les effets de l'impact electronique sur la pyridine et les diazines isomeres, Bull. Soc. Roy. Sci. Liege, 1965, 34, 337. [all data]

Bredereck, Gompper, et al., 1957
Bredereck, H.; Gompper, R.; Morlock, G., Eine neue pyrimidin-synthese, Chem. Ber., 1957, 90, 942-952. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, References

• Symbols used in this document:
  

  AE	Appearance energy
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  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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