ammonium cyanide
{{chembox
| Watchedfields = changed
| verifiedrevid = 422039176
| Name = Ammonium cyanide
| ImageFile = Ammonium cyanide.png
| ImageFile1 = Ammonium-cyanide-3D-vdW.png
| ImageSize = 120px
| ImageNameL2 = Space-filling model of the ammonium cation
| ImageNameR2 = Space-filling model of the cyanide anion
| IUPACName =
| OtherNames =
| SystematicName =
| Section1 = {{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 140210
| InChI = 1/CN.H3N/c1-2;/h;1H3/q-1;/p+1
| InChIKey = ICAIHGOJRDCMHE-IKLDFBCSAW
| SMILES = [C-]#N.[NH4+]
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/CN.H3N/c1-2;/h;1H3/q-1;/p+1
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = ICAIHGOJRDCMHE-UHFFFAOYSA-O
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 12211-52-8
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 898Y75UR3N
| PubChem = 159440
}}
| Section2 = {{Chembox Properties
| Formula = {{chem2|[NH4]CN}}
| MolarMass = 44.0559 g/mol
| Appearance = colourless crystalline solid
| Density = 1.02 g/cm3
| Solubility = very soluble
| SolubleOther = very soluble in alcohol
| MeltingPt = 36 °C (decomp.)
| BoilingPtC =
| BoilingPt_notes =
| RefractIndex =
}}
| Section3 = {{Chembox Structure
| Coordination =
| CrystalStruct = cubic
}}
| Section4 =
| Section5 =
| Section6 =
| Section8 = {{Chembox Related
| OtherAnions = {{ubl|Ammonium hydroxide|Ammonium azide|Ammonium nitrate}}
| OtherCations = {{ubl|Sodium cyanide|Potassium cyanide}}
| OtherCompounds = {{ubl|Ammonia|Hydrogen cyanide}}
}}
}}
Ammonium cyanide is an unstable inorganic compound with the chemical formula {{chem2|NH4CN|auto=1}}. It is the ammonium salt of hydrogen cyanide. It consists of ammonium cations {{chem2|NH4+}} and cyanide anions {{chem2|CN-}}. Its structural formula is {{chem2|[NH4]+[C\tN]-}}.
Uses
Ammonium cyanide is generally used in organic synthesis.{{cn|date=May 2024}} Being unstable, it is not shipped or sold commercially.
Preparation
Ammonium cyanide is prepared by combining solutions of hydrogen cyanide and ammonia:{{cn|date=May 2024}}
:{{chem2|HCN + NH3 → NH4CN}}
It may be prepared by the reaction of calcium cyanide and ammonium carbonate:{{cn|date=May 2024}}
:{{chem2|Ca(CN)2 + (NH4)2CO3 → 2 NH4CN + CaCO3}}
In dry state, ammonium cyanide is made by heating a mixture of potassium cyanide or potassium ferrocyanide with ammonium chloride and condensing the vapours into ammonium cyanide crystals:{{cn|date=May 2024}}
:{{chem2|KCN + NH4Cl → NH4CN + KCl}}
Reactions
Ammonium cyanide decomposes to ammonia and hydrogen cyanide, often forming a black polymer of hydrogen cyanide:{{Cite book |doi = 10.1007/3-540-54752-5_195|chapter = Hydrogen cyanide polymerization: A preferred cosmochemical pathway|title = Bioastronomy: The Search for Extraterrestrial Life—The Exploration Broadens|volume = 390|pages = 85–87|series = Lecture Notes in Physics|year = 1991|last1 = Matthews|first1 = Clifford N|isbn = 978-3-540-54752-5}}
:{{chem2|NH4CN → NH3 + HCN}}
It undergoes salt metathesis reaction in solution with a number of metal salts to form metal–cyanide complexes.
Reaction with ketones and aldehydes yield aminonitriles, as in the first step of the Strecker amino acid synthesis:
:{{chem2|NH4CN + (CH3)2CO → (CH3)2C(NH2)CN + H2O}}
Toxicity
{{see|Cyanide poisoning}}
Ammonium cyanide is highly toxic.
Notes
{{Reflist}}
References
- A. F. Wells, Structural Inorganic Chemistry, 5th ed., Oxford University Press, Oxford, UK, 1984.
{{Ammonium salts}}
{{Cyanides}}