Reduction of Carbonyl Groups to Methylene Groups
Wolff-Kishner Reduction: Application
The Wolff-Kishner reduction is the second step in the Haworth synthesis of naphthalene derivatives.
In the first step of the synthesis, bromobenzene and malonic anhydride undergo a Friedel-Crafts acylation. Since the resulting ketogroup deactivates the β-position in the aromatic ring for another Friedel-Crafts acylation, the carbonyl function is first reduced to methylene in a Wolff-Kishner reduction followed by a Friedel-Crafts-type ringclosure.