Elbs persulfate oxidation

The Elbs persulfate oxidation is the organic reaction of phenols with alkaline potassium persulfate to form para-diphenols.^[1]

Additional recommended knowledge

Essential Laboratory Skills Guide

Daily Visual Balance Check

Correct Test Weight Handling Guide: 12 Practical Tips

Several review have been published.^[2][3][4]

Reaction mechanism

A reaction mechanism has been postulated accounting for the observed para substitution featuring the tautomeric para carbanion of the starting phenolate ion:^[5]

which gives a nucleophilic displacement on the peroxide oxygen of the peroxodisulfate (peroxydisulfate) ion. The intermediate sulfate group is then hydrolyzed to the alcohol.

The reaction is disadvantaged by low chemical yields with recovery of starting material and complete consumption of the persulfate. It is suggested that the phenol in many cases is a catalyst converting the persulfate into a sulfate.

References

1. ^ Elbs, K. J. Prakt. Chem. 1893, 48, 179.
2. ^ S. M. Sethna (1951). "The Elbs Persulfate Oxidation". Chem. Rev. 49 (1): 91-101. doi:10.1021/cr60152a002.
3. ^ Lee, J. B.; Uff, B. C. Quart. Rev. 1967, 21, 453. (Review)
4. ^ Behrman, E. J. Org. React. 1988, 35, 421-511. (Review)
5. ^ E. J. Behrman (2006). "The Elbs and Boyland-Sims peroxydisulfate oxidations". Beilstein Journal of Organic Chemistry 2 (1): 22. doi:10.1186/1860-5397-2-22.

See also

• Boyland-Sims oxidation