Tertiary butyl halide on boiling with water gives tertiary butyl alcohol. The reaction follows -

Options

A. SE mechanism
B. `S_(N)^(I)` mechanism
C. `S_(N)^(2)` mechanism
D. `E^(1)` mechanism

Answer

To solve the problem of how tertiary butyl halide reacts with water to form tertiary butyl alcohol, we can break down the process step by step.

### Step 1: Identify the Reactants and Products
- The reactant is tertiary butyl halide. For this example, we can consider tertiary butyl chloride (C4H9Cl).
- The product formed is tertiary butyl alcohol (C4H10O).

### Step 2: Write the Structures
- The structure of tertiary butyl chloride is:
```
CH3
|
CH3 - C - Cl
|
CH3
```
- The structure of tertiary butyl alcohol is:
```
CH3
|
CH3 - C - OH
|
CH3
```

### Step 3: Understand the Mechanism
- The reaction occurs in the presence of water, which acts as a nucleophile.
- The mechanism of the reaction is a nucleophilic substitution, which can follow either SN1 or SN2 pathways.

### Step 4: Determine the Mechanism
- For tertiary butyl halide, the SN1 mechanism is favored because:
- Tertiary carbocations are more stable due to hyperconjugation and inductive effects.
- The first step involves the formation of a carbocation after the departure of the leaving group (Cl-).

### Step 5: Carbocation Formation
- When tertiary butyl chloride is heated with water, the chlorine atom leaves, forming a tertiary carbocation:
```
CH3
|
CH3 - C^+
|
CH3
```

### Step 6: Nucleophilic Attack
- The hydroxide ion (OH-) from water attacks the positively charged carbon atom of the carbocation:
```
CH3
|
CH3 - C - OH
|
CH3
```

### Step 7: Final Product
- The final product of the reaction is tertiary butyl alcohol (C4H10O).

### Conclusion
- The reaction of tertiary butyl halide with water follows the SN1 mechanism, resulting in the formation of tertiary butyl alcohol.

### Summary of the Mechanism
1. Tertiary butyl halide (e.g., tertiary butyl chloride) reacts with water.
2. The leaving group (Cl-) departs, forming a stable tertiary carbocation.
3. The nucleophile (OH-) attacks the carbocation, leading to the formation of tertiary butyl alcohol.