Lead(IV) acetate

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Lead(IV) acetate
Lead-tetraacetate-3D-balls.png
Names
IUPAC name
Lead(IV) acetate
Other names
Lead tetraacetate
Plumbic acetate
Identifiers
3D model (JSmol)
ChEBI
ECHA InfoCard 100.008.099
Properties
Pb(C2H3O2)4
Molar mass 443.376 g/mol
Appearance colorless or pink crystals
Odor vinegar
Density 2.228 g/cm3 (17 °C)
Melting point 175 °C (347 °F; 448 K)
Boiling point decomposes
soluble, reversible hydrolysis
Solubility reacts with ethanol
soluble in chloroform, benzene, nitrobenzene, hot acetic acid, HCl, tetrachloroethane
Hazards
Main hazards Toxic
NFPA 704
Flammability code 0: Will not burn. E.g. waterHealth code 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
0
3
0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Lead(IV) acetate or lead tetraacetate is a chemical compound with chemical formula Pb(C2H3O2)4. It is a colorless solid that is soluble in nonpolar organic solvents, indicative that it is not a salt. It is degraded by moisture and is typically stored with additional acetic acid. The compound is used in organic synthesis.[1]

Structure[edit]

In the solid state the lead(IV) centers are coordinated by four acetate ions, which are bidentate, each coordinating via two oxygen atoms. The lead atom is 8 coordinate and the O atoms form a flattened trigonal dodecahedron.[2]

Preparation[edit]

It is typically prepared by treating of red lead with acetic acid and acetic anhydride (Ac2O), which absorbs water. The net reaction is shown:[3]

Pb3O4 + 4 Ac2O → Pb(OAc)4 + 2 Pb(OAc)2

The remaining lead(II) acetate can be partially oxidized to the tetraacetate:

2 Pb(OAc)2 + Cl2 → Pb(OAc)4 + PbCl2

Reagent in organic chemistry[edit]

Lead tetraacetate is a strong oxidizing agent,[4] a source of acetyloxy groups and a general reagent for the introduction of lead into organolead compounds. Some of its many uses in organic chemistry:

oxidative cleavage of allyl alcohols

Safety[edit]

Lead(IV) acetate may be fatal if ingested, inhaled, or absorbed through skin. It causes irritation to skin, eyes, and respiratory tract. It is a neurotoxin. It affects the gum tissue, central nervous system, kidneys, blood, and reproductive system.

References[edit]

  1. ^ Mihailo Lj. Mihailović, Živorad Čeković, Brian M. Mathes (2005). "Lead(IV) Acetate". Encyclopedia of Reagents for Organic Synthesis, 8 Volume Set. Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rl006.pub2. ISBN 978-0471936237.CS1 maint: uses authors parameter (link)
  2. ^ Schürmann, M.; Huber, F. (1994). "A redetermination of lead(IV) acetate". Acta Crystallographica Section C. 50 (11): 1710–1713. doi:10.1107/S0108270194006438. ISSN 0108-2701.
  3. ^ J. C. Bailar, Jr. (1939). Lead Tetracetate. Inorganic Syntheses. 1. pp. 47–49. doi:10.1002/9780470132326.ch17. ISBN 9780470132326.
  4. ^ J. Zýka (1966). "Analytical study of the basic properties of lead tetraacetate as oxidizing agent" (PDF). Pure and Applied Chemistry. 13 (4): 569–581. doi:10.1351/pac196613040569. Retrieved 19 December 2013.
  5. ^ Organic Syntheses, Vol. 82, p.99 (2005) Article.
  6. ^ Organic Syntheses, Coll. Vol. 9, p.745 (1998); Vol. 72, p.57 (1995) Article
  7. ^ Baumgarten, Henry; Smith, Howard; Staklis, Andris (1975). "Reactions of amines. XVIII. Oxidative rearrangement of amides with lead tetraacetate". The Journal of Organic Chemistry. 40 (24): 3554–3561. doi:10.1021/jo00912a019.
  8. ^ Organic Syntheses, Coll. Vol. 6, p.161 (1988); Vol. 50, p.6 (1970) Article.
  9. ^ Organic Syntheses, Coll. Vol. 6, p.56 (1988); Vol. 55, p.114 (1976) Link
  10. ^ Ôeda, Haruomi (1934). "Oxidation of some α-hydroxy-acids with lead tetraacetate". Bulletin of the Chemical Society of Japan. 9 (1): 8–14. doi:10.1246/bcsj.9.8.
  11. ^ Organic Syntheses, Coll. Vol. 4, p.124 (1963); Vol. 35, p.18 (1955) Article.
  12. ^ M B Smith, J March. March's Advanced Organic Chemistry (Wiley, 2001) (ISBN 0-471-58589-0)
  13. ^ O3/Pb(OAc)4: a new and efficient system for the oxidative cleavage of allyl alcohols E.J. Alvarez-Manzaneda R. Chahboun , M.J. Cano, E. Cabrera Torres, E. Alvarez, R. Alvarez-Manzaneda, b, A. Haidour and J.M. Ramos López Tetrahedron Letters Volume 47, Issue 37 , 11 September 2006, Pages 6619-6622 doi:10.1016/j.tetlet.2006.07.020
  14. ^ Conversion of 1-allyl-cyclohexanol to cyclohexanone, in the proposed reaction mechanism the allyl group is first converted to a trioxalane according to conventional ozonolysis which then interacts with the alkoxy lead group
  15. ^ Myrboh, B.; Ila, H.; Junjappa, H. (1981). "One-Step Synthesis of Methyl Arylacetates from Acetophenones Using Lead(IV) Acetate". Synthesis. 2 (2): 126–127. doi:10.1055/s-1981-29358.
  16. ^ Jay K. Kochi (1965). "A New Method for Halodecarboxylation of Acids Using Lead(IV) Acetate". J. Am. Chem. Soc. 87 (11): 2500–02. doi:10.1021/ja01089a041.