. When 3 - methylbutan - 2 - ol is treated with HBr, the following reaction takes place


When 3 - methylbutan - 2 - ol is treated with HBr, the following reaction takes place: Give a mechanism for this reaction. (Hint: The secondary carbocation formed in step II rearranges to a more stable tertiary carbocation by a hydride ion shift from 3rd carbon atom.)

 methylbutan

Best Answer

Explanation:

  • The mechanism for the reaction between 3-methylbutane-2-ol and HBr is shown above.
  • In the first step, -OH group is protonated. In the second step, a molecule of water is lost to form a secondary carbocation.
  • The third step is the rearrangement of less stable secondary carbocation to more stable tertiary carbocation through a 1, 2-hydride shift.
  • The final step is the nucleophilic attack of bromide ion on tertiary carbocation to form 2-bromo-2-methylbutane.

 methylbutan

Final answer:

 methylbutan

Talk to Our counsellor