2-Cyanoguanidine

2-Cyanoguanidine
Names
	Preferred IUPAC name N′′-Cyanoguanidine
	Other names Cyanoguanidine; Dicyandiamide; Dicyanodiamide; N-cyanoguanidine; 1-cyanoguanidine; Guanidine-1-carbonitrile; Didin; DCD; Dicy;
Identifiers
CAS Number	461-58-5 ;
3D model (JSmol)	Interactive image; isomer: Interactive image; zwitterion: Interactive image;
ChEBI	CHEBI:147423;
ChemSpider	9611 ;
ECHA InfoCard	100.006.649
EC Number	207-312-8;
PubChem CID	10005;
RTECS number	ME9950000;
UNII	M9B1R0C16H ;
CompTox Dashboard (EPA)	DTXSID1020354 ;
	InChI InChI=1S/C2H4N4/c3-1-6-2(4)5/h(H4,4,5,6) Key: QGBSISYHAICWAH-UHFFFAOYSA-N ; InChI=1/C2H4N4/c3-1-6-2(4)5/h(H4,4,5,6) Key: QGBSISYHAICWAH-UHFFFAOYAY;
	SMILES N#CNC(=N)N; isomer: N#CN=C(N)N; zwitterion: N#CN=C([NH-])[NH3+];
Properties
Chemical formula	C2H4N4
Molar mass	84.082 g·mol−1
Appearance	White crystals
Density	1.4 g/cm3
Melting point	209.5 °C (409.1 °F; 482.6 K)
Boiling point	252 °C (486 °F; 525 K)
Solubility in water	41.3 g/L
Solubility in acetone	soluble
Solubility in ethanol	soluble
log P	−1.5 (est)
Henry's law; constant (kH)	2.25×10−10 (atm·m3)/mol
Acidity (pKa)	14.8
Basicity (pKb)	14.4
Magnetic susceptibility (χ)	−44.55×10−6 cm3/mol
Hazards
	Lethal dose or concentration (LD, LC):
LD50 (median dose)	>30000 mg/kg (oral, rat)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

2-Cyanoguanidine is a nitrile derived from guanidine. It is a dimer of cyanamide, from which it can be prepared.

Production and use

2-Cyanoguanidine is produced by treating cyanamide with base. It is produced in soil by decomposition of cyanamide. A variety of useful compounds are produced from 2-cyanoguanidine, guanidines and melamine. For example, acetoguanamine and benzoguanamine are prepared by condensation of cyanoguanidine with the nitrile:^[5]^[6]

(H₂N)₂C=NCN + PhCN → 1,3-(H₂N)-5-Ph(C₃N₃)

Cyanoguanidine is also used as a nitrification inhibitor in stabilized nitrogen fertilizers.^[1] It is used in the adhesive industry as a curing agent for epoxy resins.^[1] Formerly, it was used as a fuel in some explosives, and may be used as a stabilizer for nitrocellulose.^[7]

It was patented for use in the synthesis of methylphenobarbital.^[8]

Chemistry

The structure has been confirmed by X-ray crystallography.^[9] The molecule is planar with two primary amine groups attached to an imino nitrile. According to Raman spectroscopy measurements, solutions also contain a tautomer, (H₂N)HN=CN(H)CN.^[10]

2-cyanoguanidine is isomeric to ammonium dicyanamide, from which it may be prepared by heating in a closed vessel.^[1]^[11] The reaction proceeds via a zwitterionic intermediate, analogous to the Wöhler synthesis of urea from ammonium cyanate.^[11]

References

^ ^a ^b ^c ^d ^e ^f Güthner, Thomas; Mertschenk, Bernd. "Cyanamides". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a08_139.pub2. ISBN 978-3-527-30673-2.
^ International Chemical Safety Card 0650
^ Sakai, akira (30 January 2004). SIDS Initial Assessment Report, Cyanoguanidine (PDF). SIAM 17. Arona, Italy: UNEP Publications. Archived from the original (PDF) on 2017-05-17. Retrieved 24 October 2025.
^ Sigma-Aldrich Co., Dicyandiamide.
^ Deim, H.; Matthias, G.; Wagner, R. A. "Amino Resins". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a02_115.pub2. ISBN 978-3-527-30673-2.
^ Simons, J. K.; Saxton, M. R. (1953). "Benzoguanamine". Org. Synth. 33: 13. doi:10.15227/orgsyn.033.0013; Coll. Vol., vol. 4, 1963, p. 78.
^ Fedoroff, Basil T.; Sheffield, Oliver E. (1 January 1966). Encyclopedia of Explosives and Related Items: Volume 3 - Chlorides through Detonating Relays (PDF). Dover, NJ: Picatinny Arsenal. p. C-587. AD0653029. Retrieved 25 October 2025.
^ Ludwig Taub and Walter Kropp, U.S. patent 2,061,114 (1936 to Winthrop Chemical Company Inc.).
^ Hirshfeld, F. L.; Hope, H. (1980). "An X-ray determination of the charge deformation density in 2-cyanoguanidine". Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry. 36 (2): 406–415. Bibcode:1980AcCrB..36..406H. doi:10.1107/S0567740880003366.
^ Alı́a, J.M.; Edwards, H.G.M.; Garcı́a Navarro, F.J. (2001). "The imino–amino tautomeric equilibrium in cyanoguanidine dissolved in several aprotic solvents; an FT-Raman spectroscopic study". Journal of Molecular Structure. 597 (1–3): 49–55. Bibcode:2001JMoSt.597...49A. doi:10.1016/S0022-2860(01)00579-8.
^ ^a ^b Lotsch, Bettina V.; Senker, Jürgen; Schnick, Wolfgang (1 February 2004). "Characterization of the Thermally Induced Topochemical Solid-State Transformation of NH₄[N(CN)₂] into NCN=C(NH₂)₂ by Means of X-ray and Neutron Diffraction as Well as Raman and Solid-State NMR Spectroscopy" (PDF). Inorganic Chemistry. 43 (3): 895–904. doi:10.1021/ic034984f. Archived from the original (PDF) on 11 August 2017.

[Ullmann-1] ^ ^a ^b ^c ^d ^e ^f Güthner, Thomas; Mertschenk, Bernd. "Cyanamides". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a08_139.pub2. ISBN 978-3-527-30673-2.

[2] International Chemical Safety Card 0650

[3] Sakai, akira (30 January 2004). SIDS Initial Assessment Report, Cyanoguanidine (PDF). SIAM 17. Arona, Italy: UNEP Publications. Archived from the original (PDF) on 2017-05-17. Retrieved 24 October 2025.

[4] Sigma-Aldrich Co., Dicyandiamide.

[5] Deim, H.; Matthias, G.; Wagner, R. A. "Amino Resins". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a02_115.pub2. ISBN 978-3-527-30673-2.

[6] Simons, J. K.; Saxton, M. R. (1953). "Benzoguanamine". Org. Synth. 33: 13. doi:10.15227/orgsyn.033.0013; Coll. Vol., vol. 4, 1963, p. 78.

[7] Fedoroff, Basil T.; Sheffield, Oliver E. (1 January 1966). Encyclopedia of Explosives and Related Items: Volume 3 - Chlorides through Detonating Relays (PDF). Dover, NJ: Picatinny Arsenal. p. C-587. AD0653029. Retrieved 25 October 2025.

[8] Ludwig Taub and Walter Kropp, U.S. patent 2,061,114 (1936 to Winthrop Chemical Company Inc.).

[9] Hirshfeld, F. L.; Hope, H. (1980). "An X-ray determination of the charge deformation density in 2-cyanoguanidine". Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry. 36 (2): 406–415. Bibcode:1980AcCrB..36..406H. doi:10.1107/S0567740880003366.

[10] Alı́a, J.M.; Edwards, H.G.M.; Garcı́a Navarro, F.J. (2001). "The imino–amino tautomeric equilibrium in cyanoguanidine dissolved in several aprotic solvents; an FT-Raman spectroscopic study". Journal of Molecular Structure. 597 (1–3): 49–55. Bibcode:2001JMoSt.597...49A. doi:10.1016/S0022-2860(01)00579-8.

[Lotsch2004-11] Lotsch, Bettina V.; Senker, Jürgen; Schnick, Wolfgang (1 February 2004). "Characterization of the Thermally Induced Topochemical Solid-State Transformation of NH₄[N(CN)₂] into NCN=C(NH₂)₂ by Means of X-ray and Neutron Diffraction as Well as Raman and Solid-State NMR Spectroscopy" (PDF). Inorganic Chemistry. 43 (3): 895–904. doi:10.1021/ic034984f. Archived from the original (PDF) on 11 August 2017.

[1]

[2]

[4]

[3]

[5]

[6]

[7]

[8]

[9]

[10]

[11]