Wharton reaction

The Wharton reaction is the chemical reaction of α,β-epoxy-ketones with hydrazine to give allylic alcohols.^[1][2][3]

Additional recommended knowledge

What is the Correct Way to Check Repeatability in Balances?

What is the Sensitivity of my Balance?

Daily Sensitivity Test

Dupuy has developed an improved procedure.^[4]

Reaction mechanism

The mechanism of the Wharton reaction begins with reaction of the ketone (1) with hydrazine to form a hydrazone (2). Rearrangement of the hydrazone gives intermediate 3, which can decompose giving off nitrogen gas forming the desired product 4. Stork et al. have investigated the mechanism of the final decomposition and found that it can proceed by an ionic mechanism or a radical mechanism depending on reaction temperature, solvent used, and structure of intermediate 3.^[5]

Notice that the alcohol retains the configuration of the starting epoxide.

References

1. ^  Wharton, P. S.; Bohlen, D. H. J. Org. Chem. 1961, 26, 3615.
2. ^  Wharton, P. S. J. Org. Chem. 1961, 26, 4781.
3. ^  Chamberlin, A. R.; Sall, D. J. Comp. Org. Syn. 1991, 8, 927-929. (Review)
4. ^  Dupuy, C.; Luche, J. L. Tetrahedron 1989, 45, 3437.
5. ^  Stork, G. A. et al. J. Am. Chem. Soc. 1977, 99, 7067.

See also

• Eschenmoser fragmentation
• Grob fragmentation
• Wolff-Kishner reduction