Dicobalt_edetate

Dicobalt edetate

Dicobalt edetate

Chemical compound

Dicobalt edetate is the coordination compound with the approximate formula Co2(EDTA)(H2O)6. It is a derivative of the (non-natural) amino acid ethylenediaminetetraacetate.

Quick Facts Names, Identifiers ...

Solutions of this solid have been used in Europe as an antidote to cyanide poisoning, with the trade name Kelocyanor.[1] However, dicobalt edetate is itself toxic, particularly if there is not enough cyanide in the blood to react with it, so it is only suitable for serious cases of poisoning. In the past, workplaces in the UK that handle cyanide were recommended to keep a 'Kelocyanor kit', to be taken to the hospital along with the patient, but this practice has been discontinued since it may mislead doctors into using the antidote unnecessarily.[2]

Structure

The compound is polymeric in the crystalline form. Half of the Co2+ ions are bound to the EDTA2− and the other Co2+ ions are bound to four water ligands as well as carboxylate ligands on the [Co(EDTA)]2− entity.[3] In aqueous solution, depolymerization occurs to give [Co(EDTA)]2− and [Co(H2O)6]2+ ions, each of which is kinetically labile and has a high affinity for cyanide.

Oxidation of [Co(II)(EDTA)]2− gives [Co(III)(EDTA)]−, which is so kinetically inert that it can be resolved optically.[4]

References

  1. [1]
    Pickering WG (December 1985). "Cyanide toxicity and the hazards of dicobalt edetate". Br Med J (Clin Res Ed). 291 (6509): 1644. doi:10.1136/bmj.291.6509.1644-a. PMC 1418389. PMID 2866807.
  2. [2]
    "Cyanide poisoning – New recommendations on first aid treatment". Health and Safety Executive. Archived from the original on 20 October 2009.
  3. [3]
    E. F. K. Mccandlish, T. K. Michael; Rose, N. J.; Neal, J. A.; Lingafelter, E. C.; Rose, N. J. (1978). "Comparison of the Structures and Aqueous Solutions of [(O-Phenylenediaminetetraacetato(2-)]Cobalt(II) and [Ethylenediaminetetraacetato(2-)]Cobalt(II)". Inorg. Chem. 17 (6): 1383–94. doi:10.1021/ic50184a001.
  4. [4]
    Dwyer, F. P.; Garvan, F. L. (1960). "Resolution of the Ethylenediaminetetraacetatocobaltate(III) Ion". Inorganic Syntheses. Vol. VI. pp. 192–4. doi:10.1002/9780470132371.ch61. ISBN 978-0-470-13237-1. {{cite book}}: |journal= ignored (help)
Share this article:

This article uses material from the Wikipedia article Dicobalt_edetate, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.