Explain the conversion of `C_(6)H_(5)underset("Phenyl acetaldehyde")underset((A))(CH_(2))CHOrarr`
`{:(" "6" "5" "4" "3" "2" "1),(C_(6)H_(5)CH_(2)-CH-CH_(2)-CH_(2)-C-CH_(3)),(" "|" "||),(" "OH" "O),(" "(B)),(" 5-Hydroxy-6-phenylhexan-2-one"):}`
by using Grignard reagent of `BrCH_(2)CH_(2)-underset(O)underset(||)C-CH_(3)(I)` and why (C=O) group is protected ?

Explanation

To explain the conversion of phenyl acetaldehyde (C₆H₅CH₂CHO) into 5-hydroxy-6-phenylhexan-2-one using a Grignard reagent, we will follow a step-by-step approach.

### Step 1: Understanding the Reactants and Products
- **Reactant**: Phenyl acetaldehyde (C₆H₅CH₂CHO) contains a carbonyl group (C=O) and is an aldehyde.
- **Product**: 5-hydroxy-6-phenylhexan-2-one has a hydroxyl group (-OH) and a ketone group (C=O).

### Step 2: Protecting the Carbonyl Group
Before using the Grignard reagent, we need to protect the carbonyl group in the phenyl acetaldehyde. This is crucial because Grignard reagents react with carbonyl groups, and we want to prevent this reaction from occurring at this stage.
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