In which of the following reaction tertiary butyl benzene is formed ?

Options

A.
B.
C.
D. All of these

Answer

To determine in which reaction tertiary butyl benzene is formed, we will analyze each of the provided options step by step.

### Step-by-Step Solution:

1. **Understanding Tertiary Butyl Benzene Formation**:
Tertiary butyl benzene is formed when a tertiary butyl group is introduced to a benzene ring through an electrophilic substitution reaction.

2. **Option A: Benzene with Tertiary Butyl Alcohol and Boron Trifluoride**:
- Benzene has a high electron density and can react with electrophiles.
- Tertiary butyl alcohol can generate a tertiary butyl carbocation when treated with boron trifluoride (BF3), which acts as a Lewis acid.
- The carbocation then reacts with benzene, leading to the formation of tertiary butyl benzene.
- **Conclusion**: This option produces tertiary butyl benzene.

3. **Option B: Benzene with 2-Methylpropene and H2SO4**:
- In this reaction, 2-methylpropene reacts with sulfuric acid to form a tertiary carbocation.
- This carbocation can then react with benzene, leading to the formation of tertiary butyl benzene.
- **Conclusion**: This option also produces tertiary butyl benzene.

4. **Option C: Benzene with Alkyl Halide and Aluminum Trichloride**:
- Here, an alkyl halide (2-chloro-2-methylpropane) reacts with aluminum trichloride to form a tertiary carbocation.
- This carbocation can then react with benzene, resulting in the formation of tertiary butyl benzene.
- **Conclusion**: This option also produces tertiary butyl benzene.

5. **Option D: Summary of Findings**:
- All three reactions (A, B, and C) lead to the formation of tertiary butyl benzene.
- Therefore, the correct answer is that tertiary butyl benzene is formed in all the reactions provided.

### Final Answer:
**Tertiary butyl benzene is formed in all of the reactions (Options A, B, and C).**