Which of the following reaction does ...

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

`CH_(3) -overset(CH_(3))overset(|)underset(CH_(3))underset(|)(C) -O - Na + CH_(3) CH_(2) Br to`

`CH_(3)-overset(CH_(3))overset(|)underset(CH_(3))underset(|)(C) - Br + CH_(3) CH_(2) ON a to `

`CH_(3) -overset(H)overset(|)underset(H)underset(|)(C ) - Br + CH_(3) ON a to `

`CH_(3) l - overset(CH_(3))overset(|)underset(H)underset(|)(C) - ON a + CH_(3) - overset(CH_(2)Br)overset(|)(CH_(2)) to`

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The correct Answer is:

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.