Treatment of benzene with `"CO"//HCl` in the presence of anhydrous `AlCl_(3)//CuCl` followed by reaction with `Ac_(2)"O"//NaOAc` gives a compound X. Reaction of X with `H_(2)//Pd//c` followed by treatment with `H_(3)PO_(4)` gives another compound Y. The compound Y is :

Options

A.
B.
C.
D.

Explanation

To solve the problem step by step, let's analyze the reactions and transformations involved in the synthesis of compound Y from benzene.

### Step 1: Friedel-Crafts Acylation
- **Reaction**: Benzene reacts with carbon monoxide (CO) and hydrochloric acid (HCl) in the presence of anhydrous AlCl₃/CuCl.
- **Mechanism**: This reaction leads to the formation of benzaldehyde (C₆H₅CHO) through the generation of an acylium ion (C₆H₅C^+=O) which then reacts with benzene.

**Result**: The product formed in this step is benzaldehyde (C₆H₅CHO).

### Step 2: Reaction with Acetic Anhydride
- **Reaction**: Benzaldehyde (C₆H₅CHO) is then treated with acetic anhydride (Ac₂O) in the presence of sodium acetate (NaOAc).
- **Mechanism**: This reaction leads to the formation of an aromatic ketone, specifically, the product is acetophenone (C₆H₅COCH₃).

**Result**: The compound X formed in this step is acetophenone (C₆H₅COCH₃).

### Step 3: Hydrogenation of Compound X
- **Reaction**: Acetophenone (C₆H₅COCH₃) is then subjected to hydrogenation using hydrogen gas (H₂) in the presence of palladium on carbon (Pd/C).
- **Mechanism**: This reaction reduces the carbonyl group (C=O) of acetophenone to a secondary alcohol, yielding 1-phenylethanol (C₆H₅CH(OH)CH₃).

**Result**: The compound formed after this step is 1-phenylethanol (C₆H₅CH(OH)CH₃).

### Step 4: Dehydration of Alcohol
- **Reaction**: The resulting alcohol (1-phenylethanol) is then treated with phosphoric acid (H₃PO₄).
- **Mechanism**: This reaction leads to the dehydration of the alcohol, resulting in the formation of an alkene, specifically styrene (C₆H₅CH=CH₂).

**Result**: The final compound Y formed is styrene (C₆H₅CH=CH₂).

### Final Answer
The compound Y is styrene (C₆H₅CH=CH₂).

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