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Iron(III) acetate

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Iron(III) acetate
Names
IUPAC name
iron(III) acetate
Other names
basic iron(III) acetate, iron(III) oxyacetate, iron(III) Acetate
Identifiers
3D model (JSmol)
ChemSpider
UNII
  • InChI=1/3C2H4O2.Fe/c3*1-2(3)4;/h3*1H3,(H,3,4);/q;;;+3/p-3
    Key: PVFSDGKDKFSOTB-DFZHHIFOAZ
  • CC(=O)[O-].CC(=O)[O-].CC(=O)[O-].[Fe+3]
  • coordination complex: O1[C-](C)O[Fe+3]6([O-2]23)([OH2])(O[C-](C)O4)O[C-](C)O[Fe+3]24([OH2])(O[C-](C)O5)O[C-](C)O[Fe+3]135([OH2])O[C-]C(C)O6
Properties
C13H27Fe3O18
Molar mass 650.9 g/mol
Appearance brownish-red powder
Insoluble
Solubility soluble in ethanol[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Ferric acetate is the iron compound with the formula Fe3O(O2CCH3)6(H2O)3]O2CCH3. This red brown solid is the acetate salt of the coordination complex [Fe3O(OAc)6(H2O)3]+ (OAc is CH3CO2). Commonly, the salt is known as "basic iron acetate".[2] The formation of the red-brown complex was once used as a test for ferric ions.[3]

Structure and synthesis

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structure of the cation called basic iron acetate as determined from X-ray crystallography[4]

Basic iron acetate forms on treating aqueous solutions of iron(III) sources with acetate salts. It is slowly soluble in water and poorly soluble in acetic acid.[5] A typical precursor is freshly precipitated iron oxide/hydroxide, which is halide-free.[6]

Early work showed that the cation is trinuclear.[7] The Fe centres are equivalent, each being octahedral, being bound to six oxygen ligands, including a triply bridging oxide at the center of the equilateral triangle.[8] The compound was an early example of a molecular complex of iron that features an oxide ligand. The cation has idealized D3h symmetry.

Reactions

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The terminal aqua ligands on the trimetallic framework can be substituted with other ligands, such as pyridine and dimethylformamide. Many different salts are known by exchanging the anion, e.g. [Fe33-O)(OAc)6(H2O)3]Cl. Reduction of the cation affords the neutral mixed-valence derivative that contains one ferrous and two ferric centers.[2] Mixed metal species are known such as [Fe2CoO(OAc)6(H2O)3].[9]

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Chromium(III), ruthenium(III), vanadium(III), manganese(III) and rhodium(III) form analogous compounds.[10] Iron(III) acetate (lacking the oxo ligand) has been claimed as a red coloured compound from the reaction of silver acetate and iron(III) chloride.[11]

Uses

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Materials prepared by heating iron, acetic acid, and air, loosely described as basic iron acetates, are used as dyes and mordants.[2]

Iron acetate is often brushed upon untreated wood to give it an aged appearance.[citation needed]

See also

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References

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  1. ^ "Iron(III) Acetate". EndMemo. Retrieved 18 April 2015.
  2. ^ a b c J., Burgess; M. V., Twigg (2005). R. Bruce, King; J., Wiley (eds.). Encyclopedia of inorganic chemistry (2nd ed.). New York: Wiley. ISBN 978-0-470-86078-6.
  3. ^ H., Brearley; F., Ibbotson (1902). The Analysis of Steel-Works Materials. London; New York: Longmans, Green. Archived from the original on 18 April 2015.
  4. ^ Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. pp. 4–63. ISBN 0-8493-0487-3.
  5. ^ W., Simon (March 2007). Manual of Chemistry. Read Books. p. 474. ISBN 978-1406733358.
  6. ^ H. Lux (1963). "Basic Iron(III) Acetate". In Georg Brauer (ed.). Handbook of Preparative Inorganic Chemistry. p. 1508.
  7. ^ Weinland, R.; Dinkelacker, P. (July 1909). "Über Salze einer Hexaacetato(formiato)-trichrombase. II". Berichte der Deutschen Chemischen Gesellschaft. 42 (3): 2997–3018. doi:10.1002/cber.19090420318.
  8. ^ Figgis, B. N.; Robertson, G. B. (13 February 1965). "Crystal-Molecular Structure and Magnetic Properties of Cr3(CH3.COO)6OCl.5H2O". Nature. 205 (4972): 694–695. Bibcode:1965Natur.205..694F. doi:10.1038/205694a0. S2CID 4283321. This paper describes the isostructure chromium and iron compounds.
  9. ^ Blake, Antony B.; Yavari, Ahmad; Hatfield, William E.; Sethulekshmi, C. N. (1985). "Magnetic and spectroscopic properties of some heterotrinuclear basic acetates of chromium(III), iron(III), and divalent metal ions". Journal of the Chemical Society, Dalton Transactions (12): 2509–2520. doi:10.1039/DT9850002509.
  10. ^ Holleman, Arnold Frederik; Wiberg, Egon (2001), Wiberg, Nils (ed.), Inorganic Chemistry, translated by Eagleson, Mary; Brewer, William, San Diego/Berlin: Academic Press/De Gruyter, ISBN 0-12-352651-5
  11. ^ Paul, Ram C.; Narula, Ramesh C.; Vasisht, Sham K. (December 1978). "Iron(III) acetates". Transition Metal Chemistry. 3 (1): 35–38. doi:10.1007/BF01393501. S2CID 94447648.