Question

What are X and Y respectively in the following sets of reactions? (major product)

• A.

  

• B.

  

• C.

  

• D.

  

Hint:

Use \( \ce{PBr3} \) to convert alcohols to alkyl bromides.
HBr with peroxides follows anti-Markovnikov rule due to free radical addition.

Answer 1

The Correct Option is C

Step 1: The reaction of \( \ce{CH3CH2CH2OH} \) with \( \ce{PBr3} \) gives \( \ce{CH3CH2CH2Br} \) — a substitution reaction replacing –OH with –Br. Step 2: The reaction of propene (\( \ce{CH3CH=CH2} \)) with HBr in the presence of benzoyl peroxide (\( \ce{(C6H5COO)2} \)) proceeds via anti-Markovnikov addition due to free radical mechanism, yielding \( \ce{CH2BrCH2CH3} \) as major product. Step 3: So, X is \( \ce{CH3CH2CH2Br} \) and Y is \( \ce{CH2BrCH2CH3} \), which corresponds to option (3).