Write chemical reaction to affect the following transformations :
Benzyl alcohol to phenynylethanoic acid

Explanation

To convert benzyl alcohol to phenyl ethanoic acid, we can follow these steps:

### Step 1: Conversion of Benzyl Alcohol to Benzyl Bromide
1. **Starting Material**: Benzyl alcohol (C6H5CH2OH).
2. **Reagent**: HBr (Hydrobromic acid).
3. **Reaction**: The hydroxyl (-OH) group of benzyl alcohol is protonated by HBr, making it a better leaving group. The bromide ion (Br-) then acts as a nucleophile and replaces the -OH group.

**Chemical Reaction**:
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