1,3-Diazine
- Formula: C4H4N2
- Molecular weight: 80.0880
- IUPAC Standard InChIKey: CZPWVGJYEJSRLH-UHFFFAOYSA-N
- 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
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 46.80 ± 0.36 | kcal/mol | Ccr | Nabavian, Sabbah, et al., 1977 | Reanalyzed by Pedley, Naylor, et al., 1986, Original value = 46.15 ± 0.47 kcal/mol |
![]() | 46.83 ± 0.33 | kcal/mol | Ccb | Tjebbes, 1962 | Reanalyzed by Cox and Pilcher, 1970, Original value = 46.99 ± 0.24 kcal/mol |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 34.23 ± 0.44 | kcal/mol | Ccr | Nabavian, Sabbah, et al., 1977 | |
![]() | 35.04 ± 0.20 | kcal/mol | Ccb | Tjebbes, 1962 | |
Quantity | Value | Units | Method | Reference | Comment |
![]() | -547.06 ± 0.42 | kcal/mol | Ccr | Nabavian, Sabbah, et al., 1977 | |
![]() | -547.88 ± 0.20 | kcal/mol | Ccb | Tjebbes, 1962 |
Phase change data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, IR Spectrum, 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 as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 396.7 | K | N/A | Weast and Grasselli, 1989 | BS |
Quantity | Value | Units | Method | Reference | Comment |
![]() | 12. ± 2. | kcal/mol | AVG | N/A | Average of 7 values; Individual data points |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, IR Spectrum, 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 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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -14.8 | kcal/mol | KinS | Wovkulich and Atwood, 1980 | solvent: Hexane; The data rely on the enthalpy and entropy of activation for the forward reaction, 25.4 ± 1.1 kcal/mol and 13.0±14.6 J/(mol K) Dennenberg and Darensbourg, 1972, and also on the enthalpy and entropy of activation for the Cr-CO dissociation in Cr(CO)6, 40.20 ± 0.60 kcal/mol and 94.6±6.3 J/(mol K) Graham and Angelici, 1967. The latter data were obtained in decalin; MS |
(cr) +
(l) = C10H5NO5W (cr) +
(g)
By formula: C6O6W (cr) + C4H4N2 (l) = C10H5NO5W (cr) + CO (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 8.27 | kcal/mol | N/A | Nakashima and Adamson, 1982 | The reaction enthalpy was calculated from the enthalpy of the reaction W(CO)6(solution) + py(solution) = W(CO)5(py)(solution) + CO(solution) in cyclohexane, 6.55 ± 0.69 kcal/mol, together with the enthalpies of solution of W(CO)6(cr), W(CO)5(py)(cr), and py(l), 35.7, 36.4, and 1.9 kcal/mol, respectively Nakashima and Adamson, 1982.; MS |
C4H3N2- + =
By formula: C4H3N2- + H+ = C4H4N2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 385.2 ± 2.5 | kcal/mol | TDEq | Meot-ner and Kafafi, 1988 | gas phase; Acid: pyrimidine. Anchored to 88MEO scale, not "87 acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
![]() | 376.80 ± 0.70 | kcal/mol | N/A | Wren, Vogelhuber, et al., 2012 | gas phase; B |
![]() | 376.9 ± 2.0 | kcal/mol | TDEq | Meot-ner and Kafafi, 1988 | gas phase; Acid: pyrimidine. Anchored to 88MEO scale, not "87 acidity scale; B |
(solution) +
(solution) = C10H5NO5W (solution) +
(solution)
By formula: C6O6W (solution) + C4H4N2 (solution) = C10H5NO5W (solution) + CO (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 6.55 ± 0.69 | kcal/mol | PC | Nakashima and Adamson, 1982 | solvent: Cyclohexane; MS |
![]() | 5.95 ± 0.69 | kcal/mol | PC | Nakashima and Adamson, 1982 | solvent: Benzene; MS |
![]() | 4.40 ± 0.1 | kcal/mol | PC | Nakashima and Adamson, 1982 | solvent: Tetrahydrofuran; MS |
C39H68O3P2W (solution) + (solution) = C44H71NO3P2W (solution) +
(g)
By formula: C39H68O3P2W (solution) + C4H4N2 (solution) = C44H71NO3P2W (solution) + H2 (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -9.49 ± 0.50 | kcal/mol | RSC | Gonzalez, Zhang, et al., 1988 | solvent: Toluene; MS |
![]() | -9.99 ± 0.50 | kcal/mol | RSC | Gonzalez, Zhang, et al., 1988 | solvent: Tetrahydrofuran; MS |
C14H10CrN2O4 (cr) = 2 (g) + 4
(g) +
(cr)
By formula: C14H10CrN2O4 (cr) = 2C4H4N2 (g) + 4CO (g) + Cr (cr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | >47.6 | kcal/mol | TD-HFC | Adedeji, Connor, et al., 1978 | The reaction enthalpy is a low limit Adedeji, Connor, et al., 1978.; MS |
C8H6MoO3 (solution) + 3 (solution) = C18H15MoN3O3 (solution) +
(solution)
By formula: C8H6MoO3 (solution) + 3C4H4N2 (solution) = C18H15MoN3O3 (solution) + C5H6 (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -16.7 ± 0.69 | kcal/mol | RSC | Nolan, Hoff, et al., 1985 | solvent: Pyridine; Reaction temperature: 323 K; MS |
+
= C4H4N3O-
By formula: NO- + C4H4N2 = C4H4N3O-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 16.6 ± 2.3 | kcal/mol | N/A | Le Barbu, Schiedt, et al., 2002 | gas phase; Affinity is difference in EAs of lesser solvated species; B |
C9H9CrN3O3 (solution) + 3 (solution) = C18H15CrN3O3 (solution) + 3
(solution)
By formula: C9H9CrN3O3 (solution) + 3C4H4N2 (solution) = C18H15CrN3O3 (solution) + 3C2H3N (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -11.5 ± 0.91 | kcal/mol | RSC | Mukerjee, Lang, et al., 1992 | solvent: Tetrahydrofuran; MS |
C7H9Cl2NPd (solution) + (l) = (PdCl2(C5H5N)2) (solution) +
(solution)
By formula: C7H9Cl2NPd (solution) + C4H4N2 (l) = (PdCl2(C5H5N)2) (solution) + C2H4 (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -13.8 ± 0.41 | kcal/mol | RSC | Partenheimer and Durham, 1974 | solvent: Dichloromethane; MS |
C10H5NO5W (cr) + (g) =
(g) +
(g)
By formula: C10H5NO5W (cr) + CO (g) = C6O6W (g) + C4H4N2 (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 20. ± 2.4 | kcal/mol | DSC | Daamen, van der Poel, et al., 1979 | Please also see Meester, Vriends, et al., 1976.; MS |
C12H16CrO5 (solution) + (solution) =
(solution) + C10H5CrNO5 (solution)
By formula: C12H16CrO5 (solution) + C4H4N2 (solution) = C7H16 (solution) + C10H5CrNO5 (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -20.1 ± 0.41 | kcal/mol | PAC | Yang, Vaida, et al., 1988 | solvent: Heptane; MS |
C39H66MoO3P3 (solution) + (solution) = C44H71MoNO3P2 (solution)
By formula: C39H66MoO3P3 (solution) + C4H4N2 (solution) = C44H71MoNO3P2 (solution)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -16.9 ± 0.60 | kcal/mol | RSC | Zhang, Gonzalez, et al., 1991 | solvent: Toluene; MS |
(cr) + 3
(g) = C18H15MoN3O3 (cr) + 3
(g)
By formula: C6MoO6 (cr) + 3C4H4N2 (g) = C18H15MoN3O3 (cr) + 3CO (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -12.0 ± 1.7 | kcal/mol | HFC | Adedeji, Connor, et al., 1978 | MS |
(cr) + 3
(g) = C18H15N3O3W (g) + 3
(g)
By formula: C6O6W (cr) + 3C4H4N2 (g) = C18H15N3O3W (g) + 3CO (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | -13.1 ± 2.0 | kcal/mol | HFC | Adedeji, Connor, et al., 1978 | MS |
C10H5CrNO5 (cr) + (g) =
(g) +
(g)
By formula: C10H5CrNO5 (cr) + CO (g) = C6CrO6 (g) + C4H4N2 (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 18. ± 1. | kcal/mol | DSC | Daamen, van der Poel, et al., 1979 | MS |
C10H5MoNO5 (cr) + (g) =
(g) +
(g)
By formula: C10H5MoNO5 (cr) + CO (g) = C6MoO6 (g) + C4H4N2 (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 14. ± 0.7 | kcal/mol | DSC | Daamen, van der Poel, et al., 1979 | MS |
By formula: Fe+ + C4H4N2 = (Fe+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 47.5 ± 1.9 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Cr+ + C4H4N2 = (Cr+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 42.4 ± 1.5 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Ti+ + C4H4N2 = (Ti+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 51.1 ± 2.5 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Mn+ + C4H4N2 = (Mn+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 38.0 ± 2.3 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Sc+ + C4H4N2 = (Sc+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 51.2 ± 2.2 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Mg+ + C4H4N2 = (Mg+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 41.5 ± 1.4 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: V+ + C4H4N2 = (V+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 48.8 ± 1.7 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Ni+ + C4H4N2 = (Ni+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 58.3 ± 2.3 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Al+ + C4H4N2 = (Al+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 38.0 ± 1.4 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Zn+ + C4H4N2 = (Zn+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 49.8 ± 1.8 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Co+ + C4H4N2 = (Co+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 58.6 ± 3.2 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
By formula: Cu+ + C4H4N2 = (Cu+ C4H4N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
![]() | 59.6 ± 2.3 | kcal/mol | CIDT | Amunugama and Rodgers, 2001 | RCD |
IR Spectrum
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), References, Notes
Data compiled by: Coblentz Society, Inc.
- LIQUID (NEAT); PERKIN-ELMER 521 (GRATING); (ADJUSTED subtractcm-1misc); 2 cm-1 resolution
- SOLUTION (10% IN CCl4 FOR 3800-1370, 10% IN CS2 FOR 1370-450 CM-1); DOW KBr FOREPRISM-GRATING; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 2 cm-1 resolution
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Mass spectrum (electron ionization)
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
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Download spectrum in JCAMP-DX format.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Japan AIST/NIMC Database- Spectrum MS-IW-3052 |
NIST MS number | 231129 |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), 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]
Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [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]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), References
- Symbols used in this document:
Tboil Boiling point cH°liquid
Enthalpy of combustion of liquid at standard conditions fH°gas
Enthalpy of formation of gas at standard conditions fH°liquid
Enthalpy of formation of liquid at standard conditions rG°
Free energy of reaction at standard conditions rH°
Enthalpy of reaction at standard conditions rS°
Entropy of reaction at standard conditions vapH°
Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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