Lead(IV) acetate

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Lead(IV) acetate
Names
IUPAC name
Lead(IV) acetate
Other names
Lead tetraacetate
Plumbic acetate
Identifiers
Jmol-3D images Image
Properties
PbC8H12O8
Molar mass 443.376 g/mol
Appearance Colorless to slight pinkish crystals
Density 2.23 (17°C)
Melting point 175-180°C [1]
Boiling point Decomposes [2]
reacts with water
Solubility reacts with alcohols
soluble in hot glacial acetic acid, slightly soluble in benzene, chloroform
Hazards
Safety data sheet Sparchem
Related compounds
Related compounds
Lead(II) acetate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Lead(IV) acetate also known as lead tetraacetate or plumbic acetate is a chemical compound, a lead salt of acetic acid, with the formula Pb(CH3COO)4.

Properties

Chemical

Lead tetraacetate reacts with water and ethanol to form lead(II) acetate, lead(II) oxide and acetic acid.

Physical

Lead tetraacetate is a white to slight pinkish crystals, soluble in hot acetic acid, chloroform or benzene. It has a vinegar like odor. It melts at 175 °C, and will decompose if heated too high. It has a density of 2.228 g/cm[1].

Availability

Lead tetraacetate is sold by chemical suppliers, though due to its sensitivity to water, it's difficult to purchase. It's best to make it yourself.

Preparation

There are a few ways to prepare lead(IV) acetate.

One method involves the reaction of minium with glacial acetic acid. This reaction produces both lead acetates as well as PbO, which can be separated via recrystallization from acetic acid. Acetic anhydride can also be used for a better yield, and if small amounts are added in the former reaction it will remove any traces of water from the reaction.

Pb3O4 + 6 CH3COOH → Pb(CH3COO)4 + Pb(CH3COO)2 + PbO + 3 H2O
Pb3O4 + 3 (CH3CO)2O → Pb(CH3COO)4 + Pb(CH3COO)2 + PbO

Another process involves the oxidation of lead(II)acetate is acetic acid with chlorine. Dry chlorine gas is bubbled through the solution, which is heated to 80 °C. This reaction produces lead(II) chloride as residue.

2 Pb(CH3COO)2 + Cl2 → Pb(CH3COO)4 + PbCl2

The resulting precipitate is filtered while hot and washed with hot glacial acetic acid. The filtrate is left to crystallize. Further recrystallization from glacial acetic acid is required to remove any PbCl2 impurities.[2]

A more accessible way involves electrolysis. There are several methods described in literature.

A method described in 1922 involves the electrolysis of lead(II) acetate with acetic acid.[3] One reaction involves the electrolysis of lead(IV) sulfate in acetic acid.[4]

Projects

  • THF synthesis
  • Aziridine synthesis
  • Hoffmann type rearrangements
  • Oxidation of n-alkanes to secondary acetates [5]

Handling

Safety

Lead(IV) acetate may be fatal if ingested or inhaled. Skin contact will cause burns and can also cause lead poisoning.

Storage

As it is sensitive to moisture and alcohols, it's best to store it in a hermetically sealed container, a desiccator or a glovebox if you have one. It is sometimes stabilized with acetic acid or acetic anhydride.

Disposal

Lead tetraacetate can be reduced with a sulfide to the insoluble lead sulfide and sent to the disposal facilities.

References

  1. http://onlinelibrary.wiley.com/doi/10.1002/9780470132326.ch17/summary
  2. http://onlinelibrary.wiley.com/doi/10.1002/9780470132326.ch17/summary
  3. http://onlinelibrary.wiley.com/doi/10.1002/bbpc.19220282116/abstract
  4. http://onlinelibrary.wiley.com/doi/10.1002/bbpc.19000072205/abstract
  5. http://www.sciencedirect.com/science/article/pii/S0040403900943041

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