Thiocyanate

For organic derivatives, see Organic thiocyanates. For the binary compound, ScN, see Scandium nitride.
Thiocyanate
Names
Preferred IUPAC name
Thiocyanate[1]
Other names
  • Rhodanide
  • Sulfocyanate
  • Sulphocyanate
  • Thiocyanide
  • Cyanosulfanide
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
UNII
  • InChI=1S/CHNS/c2-1-3/h3H/p-1 checkY
    Key: ZMZDMBWJUHKJPS-UHFFFAOYSA-M checkY
  • InChI=1/CHNS/c2-1-3/h3H/p-1
    Key: ZMZDMBWJUHKJPS-REWHXWOFAX
  • [S-C≡N]-: [S-]C#N
  • [S=C=N]-: S=C=[N-]
Properties
[SCN]−
Molar mass 58.08 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Thiocyanates are salts containing the thiocyanate anion [SCN]− (also known as rhodanide or rhodanate). [SCN]− is the conjugate base of thiocyanic acid. Common salts include the colourless salts potassium thiocyanate and sodium thiocyanate. Mercury(II) thiocyanate was formerly used in pyrotechnics.

Thiocyanate is analogous to the cyanate ion, [OCN]−, wherein oxygen is replaced by sulfur. [SCN]− is one of the pseudohalides, due to the similarity of its reactions to that of halide ions. Thiocyanate used to be known as rhodanide (from a Greek word for rose) because of the red colour of its complexes with iron.

Thiocyanate is produced by the reaction of elemental sulfur or thiosulfate with cyanide: The second reaction is catalyzed by thiosulfate sulfurtransferase, a hepatic mitochondrial enzyme, and by other sulfur transferases, which together are responsible for around 80% of cyanide metabolism in the body.[2]

Oxidation of thiocyanate inevitably produces hydrogen sulfate. The other product depends on pH: in acid, it is hydrogen cyanide, presumably via HOSCN and with a sulfur dicyanide side-product; but in base and neutral solutions, it is cyanate.[3]

  1. ^ International Union of Pure and Applied Chemistry (2014). Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013. The Royal Society of Chemistry. pp. 784, 1069. doi:10.1039/9781849733069. ISBN 978-0-85404-182-4.
  2. ^ Abraham, Klaus; Buhrke, Thorsten; Lampen, Alfonso (24 February 2015). "Bioavailability of cyanide after consumption of a single meal of foods containing high levels of cyanogenic glycosides: a crossover study in humans". Archives of Toxicology. 90 (3): 559–574. doi:10.1007/s00204-015-1479-8. PMC 4754328. PMID 25708890.
  3. ^ Wilson, I. R.; Harris, G. M. (January 1, 1961). "The oxidation of thiocyanate ion by hydrogen peroxide II: The acid-catalyzed reaction". Journal of the American Chemical Society. 83 (2): 286–289. doi:10.1021/ja01463a007.