Concept:The complete deoxygenation of a carbonyl group (\( C=O \)) down to a methylene group (\( -CH_2- \)) is achieved via specific name reactions depending on the pH environment.
Formula:$$ >C=O + 4[H] \xrightarrow{Zn-Hg \ / \ HCl} >CH_2 + H_2O $$
Solution:- The reagents Zinc amalgam (\( Zn-Hg \)) and concentrated Hydrochloric acid (\( HCl \)) create a strongly acidic reducing environment.
- This specific reagent combination and reaction pathway is definitively named the Clemmensen reduction.
Why other options are incorrect:The Wolff-Kishner reduction achieves the exact same transformation but uses basic conditions (Hydrazine / \( KOH \)). Williamson's synthesis is used to make ethers. Dow process is the industrial preparation of phenol from chlorobenzene.
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