Wharton reaction

The Wharton reaction is the chemical reaction of α,β-epoxy-ketones with hydrazine to give allylic alcohols.Ref|Wharton1961ARef|Wharton1961BRef|Chamberlin1991

Dupuy has developed an improved procedure.Ref|Dupuy1989

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.Ref|Stork1977

Notice that the alcohol retains the configuration of the starting epoxide.The reaction is named after Peter Stanley Wharton.

References

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

ee also

*Eschenmoser fragmentation
*Grob fragmentation
*Wolff-Kishner reduction