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Full skeletal formulas of cyanamide, both tautomers
Space-filling model of the cyanamide molecule, nitrile tautomer
Space-filling model of the cyanamide molecule, diimide tautomer
IUPAC names
Other names
Amidocyanogen, carbamonitrile, carbimide, carbodiimide, cyanoamine, cyanoazane, N-cyanoamine, cyanogenamide, cyanogen amide, cyanogen nitride, diiminomethane, hydrogen cyanamide, methane diimide
420-04-2 YesY
ChEBI CHEBI:16698 YesY
ChemSpider 9480 YesY
DrugBank DB02679 YesY
EC Number 206-992-3
Jmol 3D model Interactive image
KEGG D00123 YesY
PubChem 9864
RTECS number GS5950000
UNII 21CP7826LC YesY
UN number 2811
Molar mass 42.040 g/mol
Appearance Crystalline solid
Density 1.28 g/cm3
Melting point 44 °C (111 °F; 317 K)
Boiling point 260 °C (500 °F; 533 K) (decomposes)
83 °C at 6.7 Pa
140 °C at 2.5 kPa
85 g/100 ml (25 °C)
Solubility in organic solvents soluble
Vapor pressure {{{value}}}
Related compounds
Related compounds
Calcium cyanamide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Cyanamide is an organic compound with the formula CN2H2. This white solid is widely used in agriculture and the production of pharmaceuticals and other organic compounds. It is also used as an alcohol deterrent drug in Canada, Europe and Japan.[citation needed] The molecule features a nitrile group attached to an amino group. Although it is similar in structure to hydrogen cyanide, it is not as toxic. Derivatives of this compound are also referred to as cyanamides, the most common being calcium cyanamide (CaCN2).

Tautomers and self-condensations

Containing both a nucleophilic and electrophilic site within the same molecule, cyanamide undergoes various reactions with itself. Cyanamide exists as two tautomers, one with the connectivity NCNH2 and the other with the formula HNCNH ("diimide" tautomer). The NCNH2 form dominates, but in a few reactions (e.g. silylation) the diimide form appears to be important.

Cyanamide dimerizes to give 2-cyanoguanidine (dicyandiamide). This decomposition process is disfavored by acids and is inhibited by low temperatures. The cyclic trimer is called melamine.

Production, reactions, uses

Cyanamide is produced by hydrolysis of calcium cyanamide, which in turn is prepared from calcium carbide via the Frank-Caro process.

CaCN2 + H2O + CO2 → CaCO3 + H2NCN

The conversion is conducted on slurries. Consequently, most commercial cyanamide is sold as an aqueous solution.

The main reaction exhibited by cyanamide involves additions of compounds containing an acidic proton. Water, hydrogen sulfide, and hydrogen selenide react with cyanamide to give urea, thiourea, and selenourea, respectively:

H2NCN + H2E → H2NC(E)NH2 (E = O, S, Se)

In this way, cyanamide behaves as a dehydration agent and thus can induce condensation reactions. Alcohols, thiols, and amines react analogously to give alkylisoureas, "pseudothioureas," and guanidines. The anti-ulcer drug cimetidine is generated using such reactivity. Related reactions exploit the bifunctionality of cyanamide to give heterocycles, and this latter reactivity is the basis of several pharmaceutical syntheses such as the aminopyrimidine imatinib) and agrichemicals Amitrol (3-Amino-1,2,4-triazole) and Hexazinone. The hair-loss treatment Minoxidil and the anthelmintic (worm-killing) drugs Albendazole, Flubendazole, and Mebendazole feature 2-aminoimidazole substructures derived from cyanamide.[1]

Cyanamide is a common agricultural rest-breaking agent applied in spring to stimulate uniform opening of buds, early foliation and bloom. Cyanamide can effectively compensate for the moderate lack of chilling units accumulated in the previous autumn and save the harvest that would otherwise be lost. It is particularly effective for woody plants such as berries, grapes, apples, peaches and kiwifruit. Overdosage, high concentration and error in timing of application can damage the buds (especially of peach trees).[2]

Environmental aspects

Cyanamide degrades via hydrolysis to urea, an excellent fertilizer. Fungi, like Myrothecium verrucaria, accelerate this process utilizing the enzyme cyanamide hydratase.[3]


Cyanamide has a modest toxicity in humans.[4] Workplace exposure to hydrogen cyanamide sprays or exposure in people living in the vicinity of spraying have been reported as causing respiratory irritation, contact dermatitis, headache, and gastrointestinal symptoms of nausea, vomiting, or diarrhea.[4]


  1. Lua error in Module:Citation/CS1/Identifiers at line 47: attempt to index field 'wikibase' (a nil value).
  2. Powell, A. (1999). Action Program for Dormex Application on Peaches. Auburn University. Retrieved 2010-05-24.
  3. Stransky H and Amberger A (1973). "Isolation and properties of a cyanamide hydratase (EC 4.2.1) from Myrothecium verrucaria". Z. Pflanzenphysiol. 70: 74–87.
  4. 4.0 4.1 Lua error in Module:Citation/CS1/Identifiers at line 47: attempt to index field 'wikibase' (a nil value).

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