- Wolff-Kishner reduction
The Wolff-Kishner reduction is a
chemical reaction that fully reduces aketone (oraldehyde ) to analkane .Ref|Kishner1911Ref|Wolff1912The method originally involved heating the
hydrazone withsodium ethoxide in a sealed vessel at about 200 °C. Other bases have been found equally effective.Several reviews have been published.Ref|Todd1948Ref|Hutchins1991
Reaction mechanism
The most probable mechanism involves the elimination of an alkyl anion as the final step:
The mechanism first involves the formation of the hydrazone in a mechanism that is probably analogous to the formation of an
imine . Successive deprotonations eventually result in the evolution of nitrogen. The mechanism can be justified by the evolution of nitrogen as the thermodynamic driving force.Huang-Minlon modification
The Huang-Minlon modificationRef|Huang1946Ref|Huang1949 is a convenient modification of the Wolff-Kishner reduction and involves heating the
carbonyl compound,potassium hydroxide , andhydrazine hydrate together inethylene glycol in a one-pot reaction.Ref|OS1958References
#
Nicolai Kishner "J. Russ. Chem. Soc." 1911, "43", 582.
# cite journal
author =Ludwig Wolff
journal =Justus Liebigs Annalen der Chemie
year = 1912
volume = 394
issue = 1
pages = 86–108
title = Chemischen Institut der Universität Jena: Methode zum Ersatz des Sauerstoffatoms der Ketone und Aldehyde durch Wasserstoff
doi = 10.1002/jlac.19123940107
# Todd, D. "Org. React." 1948, "4", 378. (Review)
# Hutchins, R. O.; Hutchins, M. K. "Comp. Org. Syn." 1991, "8", 327-343. (Review)
# Huang-Minlon "J. Am. Chem. Soc. " 1946, "68", 2487.
# Huang-Minlon "J. Am. Chem. Soc. " 1949, "71", 3301.
#Organic Syntheses , Coll. Vol. 4, p.510 (1963); Vol. 38, p.34 (1958). ( [http://www.orgsyn.org/orgsyn/prep.asp?prep=cv4p0510 Article] )
#Organic Syntheses , Coll. Vol. 5, p.533 (1973); Vol. 43, p.34 (1963). ( [http://www.orgsyn.org/orgsyn/prep.asp?prep=cv5p0533 Article] )See also
*
Clemmensen reduction
*Haworth phenanthrene synthesis
*Raney nickel
*Wharton reaction
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