The treatment of benzene with isobutene in the presence of sulphuric acid gives

Options

A. iso`-` butylbenzene
B. `tert-` butylbenzene
C. `n-`butylbenzene
D. no reaction

Explanation

To solve the problem of what product is formed when benzene is treated with isobutene in the presence of sulfuric acid, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants are benzene (C6H6) and isobutene (C4H8). Isobutene has the structure CH2=C(CH3)2.

2. **Understand the Role of Sulfuric Acid**:
- Sulfuric acid (H2SO4) acts as a catalyst and protonates the isobutene, leading to the formation of a carbocation.

3. **Formation of Carbocation**:
- When isobutene is protonated by sulfuric acid, the double bond between carbon atoms breaks, and a tertiary carbocation is formed. The structure of the carbocation will be (CH3)3C+.

4. **Electrophilic Attack on Benzene**:
- The formed carbocation (tert-butyl cation) is a strong electrophile and will attack the benzene ring. This results in the formation of a new carbon-carbon bond.

5. **Formation of Tert-Butylbenzene**:
- After the electrophilic attack, the benzene ring undergoes a rearrangement to restore aromaticity, resulting in the formation of tert-butylbenzene (C10H14).

6. **Final Product**:
- The final product of the reaction is tert-butylbenzene.

### Conclusion:
The treatment of benzene with isobutene in the presence of sulfuric acid gives **tert-butylbenzene**.