In a set of the given reactions, acetic acid yielded a product iC.
`CH_(3)COOH+PCl_(5) to A overset(C_(6)H_(6))underset(Anh. AlCl_(3))toB overset(C_(2)H_(5)MgBr)underset("ether")toC`
Product C would be

Options

A. `CH_(3)CH(OH)C_(2)H_(5)`
B. `CH_(3)COC_(6)H_(5)`
C. `CH_(3)CH(OH)C_(6)H_(5)`
D. `CH_(3)-overset(" C"_(2)H_(5))overset(|)C(OH)C_(6)H_(5)`

Explanation

To solve the problem step by step, we will analyze each reaction in the sequence provided and determine the final product C.

### Step 1: Reaction of Acetic Acid with PCl5
- **Reaction**: \( CH_3COOH + PCl_5 \)
- **Explanation**: When acetic acid (CH3COOH) reacts with phosphorus pentachloride (PCl5), the hydroxyl group (–OH) of the carboxylic acid is replaced by a chlorine atom (–Cl). This reaction converts acetic acid into acetyl chloride (CH3COCl).
- **Product A**: \( CH_3COCl \) (acetyl chloride)

### Step 2: Friedel-Crafts Acylation with Benzene
- **Reaction**: \( CH_3COCl + C_6H_6 \) in presence of anhydrous \( AlCl_3 \)
- **Explanation**: The acetyl chloride (A) undergoes Friedel-Crafts acylation when reacted with benzene (C6H6) in the presence of anhydrous aluminum chloride (AlCl3). This results in the formation of a ketone. The chlorine atom acts as a good leaving group, allowing the acyl group (–C(O)CH3) to attach to the benzene ring.
- **Product B**: \( C_6H_5C(O)CH_3 \) (acetophenone)

### Step 3: Reaction with Grignard Reagent
- **Reaction**: \( C_6H_5C(O)CH_3 + C_2H_5MgBr \) in ether
- **Explanation**: The acetophenone (B) reacts with the Grignard reagent (C2H5MgBr). The nucleophilic ethyl group (C2H5) from the Grignard reagent attacks the carbonyl carbon of the ketone, forming a tertiary alcohol. The oxygen in the carbonyl group becomes negatively charged and is stabilized by the magnesium bromide.
- **Intermediate**: \( C_6H_5C(OH)(C_2H_5)CH_3 \) (alkoxide intermediate)

### Step 4: Protonation of the Alkoxide
- **Protonation**: The alkoxide intermediate is then protonated (usually by adding water or another proton source), resulting in the formation of the final alcohol product.
- **Product C**: \( C_6H_5C(OH)(C_2H_5)CH_3 \) (a tertiary alcohol)

### Final Product
- The final product C is a tertiary alcohol derived from the reaction of acetophenone with ethylmagnesium bromide.

### Answer
Product C would be \( C_6H_5C(OH)(C_2H_5)CH_3 \).

---