Which of the following reaction does not form ether as major product ?

Options

A. `CH_(3) -overset(CH_(3))overset(|)underset(CH_(3))underset(|)(C) -O - Na + CH_(3) CH_(2) Br to`
B. `CH_(3)-overset(CH_(3))overset(|)underset(CH_(3))underset(|)(C) - Br + CH_(3) CH_(2) ON a to `
C. `CH_(3) -overset(H)overset(|)underset(H)underset(|)(C ) - Br + CH_(3) ON a to `
D. `CH_(3) l - overset(CH_(3))overset(|)underset(H)underset(|)(C) - ON a + CH_(3) - overset(CH_(2)Br)overset(|)(CH_(2)) to`

Explanation

To determine which reaction does not form ether as the major product, we will analyze each option based on the principles of Williamson ether synthesis.

### Step-by-Step Solution:

1. **Understand Williamson Ether Synthesis**:
- The general reaction involves a sodium alkoxide (R-O-Na) reacting with an alkyl halide (R-X) to produce an ether (R-O-R') and sodium halide (NaX).
- The reaction typically follows an SN2 mechanism, which is favored with primary alkyl halides.

2. **Analyze Each Option**:
- **Option A**:
- Reactants: CH3C(CH3)2O-Na (sodium alkoxide) + CH3CH2Br (alkyl halide).
- Reaction: The alkoxide reacts with the primary alkyl halide to form ether.
- Product: CH3C(CH3)2OCH2CH3 + NaBr (ether is formed).
- Conclusion: Ether is formed as a major product.

- **Option B**:
- Reactants: CH3C(CH3)2O-Na + CH3-CHBr-CH3 (tertiary alkyl halide).
- Reaction: Tertiary alkyl halides do not undergo SN2 reactions effectively due to steric hindrance. Instead, elimination (E2 mechanism) occurs.
- Product: CH3C(CH3)=CH2 (alkene) + NaBr + H2O (no ether is formed).
- Conclusion: Ether is NOT formed as a major product.

- **Option C**:
- Reactants: CH3O-Na + CH3CH2Br (primary alkyl halide).
- Reaction: The sodium alkoxide reacts with the primary alkyl halide.
- Product: CH3OCH2CH3 + NaBr (ether is formed).
- Conclusion: Ether is formed as a major product.

- **Option D**:
- Reactants: CH3CH2CH2O-Na + CH3-CH2Br (primary alkyl halide).
- Reaction: The sodium alkoxide reacts with the primary alkyl halide.
- Product: CH3CH2OCH2CH2CH2CH3 + NaBr (ether is formed).
- Conclusion: Ether is formed as a major product.

3. **Final Conclusion**:
- The only option where ether is NOT formed as a major product is **Option B**.

### Answer:
**Option B** is the correct answer as it does not form ether as a major product.