Cobalt(II) acetate

Synthesis and structure

Like many other transition metal acetates, cobalt(II) acetate forms by the reaction of cobalt oxide or hydroxide and acetic acid: : CoO + 2CH3CO2H + 3H2O → Co(CH3CO2)2·4H2O The tetrahydrate has been shown by X-ray crystallography to adopt an octahedral structure, the central cobalt centre being coordinated by four water molecules and two acetate ligands. The analogous nickel acetate is isostructural.

Various hydrates are known including Co(CH3CO2)2·H2O and [Co(CH3CO2)2]5·0.5 H2O. These are coordination polymers:

Reactions and uses

Cobalt acetate is a precursor to various oil drying agents, catalysts that allow paints and varnishes to harden.

Anhydrous cobalt acetate is a widely used source of cobalt in the synthesis of materials, catalyst, and complexes.

Oxidation of acetic acid solutions of cobalt(II) acetate, e.g. with ozone, gives cobalt(III) acetates, which are strong oxidants.

Safety

Cobalt salts are poisonous.

References

References

1. (2003). "Cobalt diacetate tetrahydrate". Acta Crystallographica Section E.
2. (1953). "The crystal structures of nickel acetate, Ni(CH₃COO)₂·4H₂O, and cobalt acetate, Co(CH₃COO)₂·4H₂O". [[Acta Crystallogr.]].
3. (2010). "Infinite Coordination Polymers of One- and Two-dimensional Cobalt Acetates". Zeitschrift für Anorganische und Allgemeine Chemie.
4. John Dallas Donaldson, Detmar Beyersmann, "Cobalt and Cobalt Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. {{doi. 10.1002/14356007.a07_281.pub2
5. (2015). "Metal–organic framework nanosheets in polymer composite materials for gas separation". Nature Materials.
6. (2006). "Recent advances in homogeneous transition metal-catalyzed aerobic alcohol oxidations". Tetrahedron.
7. Appleton, T. G.. (1977). "Oxygen Uptake by a Cobalt(II) Complex". [[J. Chem. Educ.]].
8. (2001). "Encyclopedia of Reagents for Organic Synthesis".