1,3-Diazine

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

Go To: Top, Ion clustering data, References, Notes

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) + 1,3-Diazine (solution)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-61.9	kJ/mol	KinS	Wovkulich and Atwood, 1980	solvent: Hexane; The data rely on the enthalpy and entropy of activation for the forward reaction, 106.3 ± 4.6 kJ/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, 168.2 ± 2.5 kJ/mol and 94.6±6.3 J/(mol K) Graham and Angelici, 1967. The latter data were obtained in decalin; MS

(cr) + 1,3-Diazine (l) = C₁₀H₅NO₅W (cr) + (g)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	34.6	kJ/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, 27.4 ± 2.9 kJ/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 7.9 kJ/mol, respectively Nakashima and Adamson, 1982.; MS

C₄H₃N₂^- + = 1,3-Diazine

By formula: C₄H₃N₂^- + H⁺ = C₄H₄N₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	1612. ± 10.	kJ/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
Δ_rG°	1576.5 ± 2.9	kJ/mol	N/A	Wren, Vogelhuber, et al., 2012	gas phase; B
Δ_rG°	1577. ± 8.4	kJ/mol	TDEq	Meot-ner and Kafafi, 1988	gas phase; Acid: pyrimidine. Anchored to 88MEO scale, not "87 acidity scale; B

(solution) + 1,3-Diazine (solution) = C₁₀H₅NO₅W (solution) + (solution)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	27.4 ± 2.9	kJ/mol	PC	Nakashima and Adamson, 1982	solvent: Cyclohexane; MS
Δ_rH°	24.9 ± 2.9	kJ/mol	PC	Nakashima and Adamson, 1982	solvent: Benzene; MS
Δ_rH°	18.4 ± 0.4	kJ/mol	PC	Nakashima and Adamson, 1982	solvent: Tetrahydrofuran; MS

C₃₉H₆₈O₃P₂W (solution) + 1,3-Diazine (solution) = C₄₄H₇₁NO₃P₂W (solution) + (g)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-39.7 ± 2.1	kJ/mol	RSC	Gonzalez, Zhang, et al., 1988	solvent: Toluene; MS
Δ_rH°	-41.8 ± 2.1	kJ/mol	RSC	Gonzalez, Zhang, et al., 1988	solvent: Tetrahydrofuran; MS

C₁₄H₁₀CrN₂O₄ (cr) = 2 1,3-Diazine (g) + 4 (g) + (cr)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	>199.	kJ/mol	TD-HFC	Adedeji, Connor, et al., 1978	The reaction enthalpy is a low limit Adedeji, Connor, et al., 1978.; MS

C₈H₆MoO₃ (solution) + 3 1,3-Diazine (solution) = C₁₈H₁₅MoN₃O₃ (solution) + (solution)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-69.9 ± 2.9	kJ/mol	RSC	Nolan, Hoff, et al., 1985	solvent: Pyridine; Reaction temperature: 323 K; MS

+ 1,3-Diazine = C₄H₄N₃O^-

By formula: NO^- + C₄H₄N₂ = C₄H₄N₃O^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	69.5 ± 9.6	kJ/mol	N/A	Le Barbu, Schiedt, et al., 2002	gas phase; Affinity is difference in EAs of lesser solvated species; B

C₉H₉CrN₃O₃ (solution) + 3 1,3-Diazine (solution) = C₁₈H₁₅CrN₃O₃ (solution) + 3 (solution)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-48.1 ± 3.8	kJ/mol	RSC	Mukerjee, Lang, et al., 1992	solvent: Tetrahydrofuran; MS

C₇H₉Cl₂NPd (solution) + 1,3-Diazine (l) = (PdCl₂(C₅H₅N)₂) (solution) + (solution)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-57.7 ± 1.7	kJ/mol	RSC	Partenheimer and Durham, 1974	solvent: Dichloromethane; MS

C₁₀H₅NO₅W (cr) + (g) = (g) + 1,3-Diazine (g)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	83. ± 10.	kJ/mol	DSC	Daamen, van der Poel, et al., 1979	Please also see Meester, Vriends, et al., 1976.; MS

C₁₂H₁₆CrO₅ (solution) + 1,3-Diazine (solution) = (solution) + C₁₀H₅CrNO₅ (solution)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-84.1 ± 1.7	kJ/mol	PAC	Yang, Vaida, et al., 1988	solvent: Heptane; MS

C₃₉H₆₆MoO₃P₃ (solution) + 1,3-Diazine (solution) = C₄₄H₇₁MoNO₃P₂ (solution)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-70.7 ± 2.5	kJ/mol	RSC	Zhang, Gonzalez, et al., 1991	solvent: Toluene; MS

(cr) + 3 1,3-Diazine (g) = C₁₈H₁₅MoN₃O₃ (cr) + 3 (g)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-50.4 ± 7.0	kJ/mol	HFC	Adedeji, Connor, et al., 1978	MS

(cr) + 3 1,3-Diazine (g) = C₁₈H₁₅N₃O₃W (g) + 3 (g)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-54.7 ± 8.4	kJ/mol	HFC	Adedeji, Connor, et al., 1978	MS

C₁₀H₅CrNO₅ (cr) + (g) = (g) + 1,3-Diazine (g)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	75. ± 6.	kJ/mol	DSC	Daamen, van der Poel, et al., 1979	MS

C₁₀H₅MoNO₅ (cr) + (g) = (g) + 1,3-Diazine (g)

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	57. ± 3.	kJ/mol	DSC	Daamen, van der Poel, et al., 1979	MS

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	199. ± 7.9	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	177. ± 6.3	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	214. ± 10.	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	159. ± 9.6	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	214. ± 9.2	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	174. ± 5.9	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	204. ± 7.1	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	244. ± 9.6	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	159. ± 5.9	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	208. ± 7.5	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	245. ± 13.	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	249. ± 9.6	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

Ion clustering data

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Data compiled as indicated in comments:
RCD - Robert C. Dunbar
B - John E. Bartmess

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

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	159. ± 5.9	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	245. ± 13.	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	177. ± 6.3	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	249. ± 9.6	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	199. ± 7.9	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	174. ± 5.9	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	159. ± 9.6	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = C₄H₄N₃O^-

By formula: NO^- + C₄H₄N₂ = C₄H₄N₃O^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	69.5 ± 9.6	kJ/mol	N/A	Le Barbu, Schiedt, et al., 2002	gas phase; Affinity is difference in EAs of lesser solvated species; B

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	244. ± 9.6	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	214. ± 9.2	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	214. ± 10.	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	204. ± 7.1	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

+ 1,3-Diazine = ( • )

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

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	208. ± 7.5	kJ/mol	CIDT	Amunugama and Rodgers, 2001	RCD

References

Go To: Top, Reaction thermochemistry data, Ion clustering data, Notes

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

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Symbols used in this document:

Δ_rG° Free energy of reaction at standard conditions

Δ_rH° Enthalpy of reaction at standard conditions

Δ_rS° Entropy of reaction at standard conditions
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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Δ_rG°	Free energy of reaction at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions
Δ_rS°	Entropy of reaction at standard conditions