Synthetic Communications1, 40: 1187–1191, 2010
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397910903061043
NOVEL METHOD OF REDUCING KETONES USING
SODIUM HYDROXIDE IN ISOPROPANOL
Daniel R. Zuidema,1 Katherine J. Wert,1 Sarah L. Williams,1
Samuel T. Chill,2 Kimberly L. Holte,2 Nathanael K. Kokes,2
and Robert C. Mebane2
1Department of Chemistry, Covenant College, Lookout Mountain,
Georgia, USA
2Department of Chemistry, University of Tennessee at Chattanooga,
Chattanooga, Tennessee, USA
Ketones are readily reduced to secondary alcohols with sodium hydroxide in refluxing
isopropanol.
Keywords: Hydrogen transfer; ketone reduction; preparation of secondary alcohols; sodium hydroxide
The process of reducing a ketone to a secondary alcohol is a widely used and thor-
oughly studied synthetic technique.[1–4] Conventional methods commonly used for
the reduction of a ketone to a secondary alcohol include catalytic hydrogenation
and metal hydride reduction. Another common method employed is the Meerwein–
Ponndorf–Verley (MPV) reduction, which typically uses aluminum isopropoxide in
isopropanol.[5–7] Disadvantages to these methods include the flammability of hydro-
gen gas and metal hydride reagents and the expense of many of the catalysts. In the
MPV reduction, removal of the aluminum salts can be tedious.
In this report, we describe an attractive alternative to the aforementioned
methods that uses a solution of sodium hydroxide in isopropanol. The experimental
procedure for this method of reduction is simple and straightforward and affords
secondary alcohols in good yields. The overall reaction is described in Fig. 1, and
a summary of our results is presented in Table 1. As seen in Table 1, isolated yields
for the less volatile secondary alcohols were very good (entries 1, 3, 5, 9) but less so
for the more volatile alcohols because of product loss while removing the isopro-
panol solvent by rotary evaporation. Surprisingly, no evidence of aldol condensation
was observed for any of the ketones studied. In a typical run, the ketone was refluxed
(container open to the atmosphere) in a magnetically stirred solution of sodium
hydroxide in isopropanol. The solution was 0.25 M with respect to both the ketone
and the sodium hydroxide. The progress of the reaction was conveniently monitored
Received February 11, 2009.
Address correspondence to Daniel R. Zuidema, Department of Chemistry, Covenant College,
14049 Scenic Highway, Lookout Mountain, GA 30750, USA. E-mail: zuidema@covenant.edu
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