Silver hexafluorophosphate

Silver hexafluorophosphate
Identifiers
CAS number 26042-63-7
PubChem 168464
ChemSpider 147361 Y
Jmol-3D images Image 1
Properties
Molecular formula AgPF6
Molar mass 252.83 g/mol
Appearance Off-white powder
Solubility in water organic solvents
Hazards
MSDS External MSDS
EU classification Corrosive (C)
R-phrases R34
NFPA 704
 
3
 
 Y (verify) (what is: Y/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Silver hexafluorophosphate, sometimes referred to "silver PF-6," is an inorganic compound with the formula AgPF6.

Contents

Uses and reactions

Silver hexafluorophospate is a commonly encountered reagent in inorganic and organometallic chemistry. It is commonly used to replace halide ligands with the weakly coordinating hexafluorophosphate anion; the abstraction of the halide is driven by the precipitation of the appropriate silver halide. Illustrative is the preparation of acetonitrile complexes from a metal bromide, a reaction that would typically be conducted in a solution of acetonitrile:

AgPF6 + Re(CO)5Br + CH3CN → AgBr + [Re(CO)5(CH3CN)]PF6

AgPF6 can act as an oxidant, forming silver metal as a by-product. For example, in solution in dichloromethane, ferrocene is oxidised to ferrocenium hexafluorophosphate:[1]

AgPF6 + Fe(C5H5)2 → Ag + [Fe(C5H5)2]PF6 (E = 0.65 V)

Related reagents

In terms of their properties and applications, silver tetrafluoroborate (AgBF4) and the hexafluoroantimonate (AgSbF6) are similar to AgPF6.

Comparison with silver nitrate

Silver nitrate is a traditional and less expensive halide abstraction reagent, as indicated by its widespread use in qualitative tests for halides. Relative to AgPF6, however, silver nitrate is poorly soluble in weakly basic solvents: the nitrate anion is Lewis basic and presents an interfering ligand that precludes its use in stringent applications.

References

  1. ^ Connelly, N. G.; Geiger, W. E. (1996). "Chemical Redox Agents for Organometallic Chemistry". Chem. Rev. 96: 877–922. doi:10.1021/cr940053x. PMID 11848774.