Clemmensen Reduction (acidic conditions)
Zn(Hg) in HCl reduced the C=O into -CH2-
Wolff-Kishner Reduction (basic conditions)
NH2NH2 / KOH / ethylene glycol (a high boiling solvent) reduces the C=O into -CH2-
Overview
These reduction methods do not reduce C=C , CºC or -CO2H
The choice of method should be made based on the tolerance of other functional groups to the acidic or basic reaction conditions.
Hydride Reductions of Aldehydes and Ketones
(review of Chapter 15)