Wolff-Kishner reduction.

Explanation

### Step-by-Step Solution for Wolff-Kishner Reduction

**Step 1: Understanding the Reaction**
- The Wolff-Kishner reduction is a method used to convert carbonyl compounds (like aldehydes and ketones) into alkanes. This is achieved using hydrazine (NH2-NH2) in a basic medium, typically with potassium hydroxide (KOH).

**Step 2: Formation of Hydrazone**
- The carbonyl compound (R1C=O) reacts with hydrazine (NH2-NH2) to form a hydrazone (R1C=N-NH2) through a condensation reaction, where water is eliminated.

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