Cobalt(II) cyanate

Add links
Source: Wikipedia, the free encyclopedia.
Cobalt(II) cyanate
Identifiers
3D model (
JSmol
)
  • isocyanate: InChI=1S/2CNO.Co/c2*2-1-3;/q2*-1;+2
    Key: JXDJYNWFLIUUIU-UHFFFAOYSA-N
  • C(#N)[O-].C(#N)[O-].[Co+2]
  • isocyanate: C(=[N-])=O.C(=[N-])=O.[Co+2]
Properties
Co(OCN)2
Molar mass 142.97 g/mol
Related compounds
Other anions
 Cobalt(II) thiocyanate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Cobalt(II) cyanate is the hypothetical inorganic compound with the formula Co(OCN)2.

The simple cobalt(II) cyanate has not been proven to be made. However, the tetraisocyanatocobalt(II) ion (Co(NCO)42-) is known and its blue color and is used as a qualitative test for cobalt(II) ions.

History

Cobalt(II) cyanate was claimed to have been produced in 1952 by carefully heating pyridine cobalt(II) cyanate under vacuum. This has not been proven.[1]

In contrast, the tetraisocyanatocobalt(II) ion (Co(NCO)42-) has been identified by X-ray crystallography and is widely known.[2] After being first produced in 1871, it has been used as a qualitative test for cobalt(II).[3]

Other cyanate complexes of cobalt have been discovered, such as tetrakis(pyridine)cobalt(II) cyanate.[4]

Complexes

Tetracyanatocobaltate(II)

A solution of tetracyanatocobaltate(II)

Multiple compounds of the related tetracyanatocobaltate(II) has been structurally elucidated, such as [Co(C5H5)2]2[Co(NCO)4]. All of these complexes have an intense blue color.[2][5]

Potassium tetraisocyanatocobaltate(II) has been produced by the reaction of potassium cyanate and cobalt(II) nitrate:[6]

4 KOCN + Co(NO3)2 → K2[Co(NCO)4] + 2 KNO3

Tetracyanatocobaltate(II) salts with other counterions, such as cobaltcenium [Co(C5H5)]+ and EMIM are known.[2]

Other adducts

Cobalt(II) cyanate complexes have been produced by the addition of potassium cyanate to a soluble cobalt salt, such as

2,6-dimethylpyrazine.[8]

Structure

Although the simple cyanate is unknown, the structure of the tetracyanatocobaltate(II) ion has been elucidated. The [Co(NCO)4]2- ion consists of a nitrogen-bonded tetrahederal central cobalt atom. The cobalt-nitrogen bond length is about 1.96 Å.[2]

References

  1. doi:10.1021/ja01136a069
    .
  2. ^
    doi:10.1002/ejic.201601250
    .
  3. doi:10.1002/prac.18710030119
    .
  4. doi:10.1016/S0065-2792(08)60064-3
    .
  5. doi:10.1515/znb-1991-1218
    .
  6. doi:10.1021/ja01469a001
    .
  7. PMC 2960999
    .
  8. doi:10.1039/J19660000859
    .
Retrieved from "https://en.wikipedia.org/w/index.php?title=Cobalt(II)_cyanate&oldid=1195797636"