Reaction of benzene with isobutylchloride `(CH_3CH(CH_3)CH_2Cl)` in the presence of anhydrous `AlCl_3` yields.

Options

A. tert-butylbenzene
B. iso-butylbenzene
C. n-butylbenzene
D. chlorobenzene

Answer

To solve the problem of the reaction of benzene with isobutyl chloride in the presence of anhydrous AlCl3, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- Benzene (C6H6)
- Isobutyl chloride (CH3CH(CH3)CH2Cl)

2. **Understand the Role of AlCl3**:
- Anhydrous AlCl3 acts as a Lewis acid. It will coordinate with the chlorine atom in isobutyl chloride, facilitating the formation of a carbocation.

3. **Formation of Carbocation**:
- The reaction of isobutyl chloride with AlCl3 leads to the formation of a carbocation. The chlorine atom is removed, and we are left with the isobutyl cation:
\[ \text{Isobutyl cation: } CH_3C^+(CH_3)CH_2 \]

4. **Stability of Carbocations**:
- The isobutyl cation is a secondary carbocation. However, due to the presence of adjacent alkyl groups, it can undergo a hydride shift to form a more stable tertiary carbocation:
\[ \text{Tertiary carbocation: } (CH_3)_3C^+ \]

5. **Electrophilic Attack on Benzene**:
- The stable tertiary carbocation can now act as an electrophile and react with benzene. The benzene ring, being rich in electrons, will attack the carbocation, leading to the formation of tert-butylbenzene.

6. **Final Product**:
- The final product of this reaction is tert-butylbenzene (C6H5C(CH3)3).

### Conclusion:
The reaction of benzene with isobutyl chloride in the presence of anhydrous AlCl3 yields tert-butylbenzene.

### Answer:
**Tert-butylbenzene (C6H5C(CH3)3)**

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