NEETChemistryAlcohols Phenols and Ethers
Match List I with List II. List I (Reactions) List II (Major Products) A. Propan-1-ol + PBr ₃ I. 2-Bromo-2-methylbutane B. 3-Methylbutan-2-ol + PBr ₃ II. 1-Bromopropane C. 2-Methylpropan-1-ol + HBr III. 2-Bromo-3-methylbutane D. 2-Methylbutan-2-ol + HBr IV. 2-Bromo-2-methylpropane Choose the correct answer from the options given below:
Options
- AA - II, B - III, C - IV, D - I
- BA - II, B - I, C - IV, D - III
- CA - II, B - III, C - I, D - IV
- DA - III, B - II, C - IV, D - I
Correct answer
A. A - II, B - III, C - IV, D - I
Step-by-step solution
The reaction of alcohols with PBr ₃ generally proceeds without the formation of a free carbocation, so no rearrangement occurs. In contrast, the reaction of secondary and branched primary alcohols with HBr proceeds via carbocation intermediates, which can undergo rearrangement to form more stable carbocations. A. Propan-1-ol reacts with PBr ₃ to give 1-bromopropane directly (A - II). B. 3-Methylbutan-2-ol reacts with PBr ₃ without rearrangement to give 2-bromo-3-methylbutane (B - III). C. 2-Methylpropan-1-ol (isobu