Lead(IV) acetate

Structure

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.

Preparation

It is typically prepared by treating of red lead with acetic acid and acetic anhydride (), which absorbs water. The net reaction is shown: : The remaining lead(II) acetate can be partially oxidized to the tetraacetate by Cl2, with a by-product: :

Reagent in organic chemistry

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

• Acetoxylation of benzylic, allylic, and α-oxygen ether C−H bonds, for example the conversion of dioxane to 2-acetoxy-1,4-dioxane Organic Syntheses, Vol. 82, p. 99 (2005) Article.
• An alternative reagent to bromine in Hofmann rearrangement
• Dehydrogenation of hydrazones and hydrazines, for example that of hexafluoroacetone hydrazone to bis(trifluoromethyl)diazomethane
• Cleavage of α-hydroxy acids or 1,2-diols to their corresponding aldehydes or ketones, often replacing ozonolysis; for instance, the oxidation of di-n-butyl -tartrate to n-butyl glyoxylate.
• Reaction with alkenes to form γ-lactones
• Oxidation of alcohols carrying a δ-proton to cyclic ethers.
• Oxidative cleavage of certain allyl alcohols in conjunction with ozone:
• Transformation of 1,2-dicarboxylic acids or cyclic anhydrides to alkenes

• Conversion of acetophenones to phenyl acetic acids
• Decarboxylation of carboxylic acids to alkyl halides in the Kochi reaction

Safety

Lead(IV) acetate is toxic, because of lead. It is a neurotoxin. It badly affects the gum tissue, central nervous system, kidneys, blood, and reproductive system.

References

References

1. "Substance Information - ECHA".
2. {{cite encyclopedia. Mihailo Lj. Mihailović. (2005)
3. (1994). "A redetermination of lead(IV) acetate". Acta Crystallographica Section C.
4. J. C. Bailar, Jr.. (1939). "Inorganic Syntheses".
5. M. Baudler. (1963). "Handbook of Preparative Inorganic Chemistry, 2nd Ed.". Academic Press.
6. J. Zýka. (1966). "Analytical study of the basic properties of lead tetraacetate as oxidizing agent". Pure and Applied Chemistry.
7. (1995). "(1R,5R)-(+)-Verbenone of High Optical Purity". Organic Syntheses.
8. (1975). "Reactions of amines. XVIII. Oxidative rearrangement of amides with lead tetraacetate". The Journal of Organic Chemistry.
9. (1970). "Bis(Trifluoromethyl)Diazomethane". Organic Syntheses.
10. Robert K. Muller, Renato Joos, Dorothee Felix, Jakob Schreiber, Claude Wintner, and A. Eschenmoser. (1976). "Preparation of N-Aminoaziridines: trans-1-Amino-2,3-diphenylaziridine, 1-Amino-2-phenylaziridine, and 1-Amino-2-phenylaziridinium Acetate". Organic Syntheses.
11. (1934). "Oxidation of some α-hydroxy-acids with lead tetraacetate". Bulletin of the Chemical Society of Japan.
12. Organic Syntheses, Coll. Vol. 4, p. 124 (1963); Vol. 35, p. 18 (1955) [http://www.orgsynth.org/orgsyn/prep.asp?prep=cv4p0124 Article].
13. M B Smith, J March. ''March's Advanced Organic Chemistry'' (Wiley, 2001) ({{ISBN. 0-471-58589-0)
14. (2006). "O₃/Pb(OAc)₄: a new and efficient system for the oxidative cleavage of allyl alcohols". [[Tetrahedron Letters]].
15. Conversion of 1-allylcyclohexanol 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.
16. (1981). "One-Step Synthesis of Methyl Arylacetates from Acetophenones Using Lead(IV) Acetate". [[Synthesis (journal).
17. Jay K. Kochi. (1965). "A New Method for Halodecarboxylation of Acids Using Lead(IV) Acetate". [[J. Am. Chem. Soc.]].