Chapter 18, Problem 32P

Interpretation Introduction

Interpretation:

Compound that can remove $HBr$ more rapidly in a basic solution has to be identified.

Concept introduction:

• Catalyst: Substance which helps in increasing the rate of a particular reaction without getting consumed in the reaction.
• Base Catalyst: A catalyst which helps in increasing the rate of a particular reaction by the removal of a proton. There are two types of catalysis:

1. 1. Specific-base catalysis: Proton is completely removed before the slow step in a reaction
2. 2. General- base catalysis: Proton is completely removed during the slow step in a reaction

• Intramolecular general-base catalysis: A catalysis where catalyst is a part of the molecule that undergoes the reaction promotes the reaction in a species by completely removing a proton during the slow step in a reaction

Explanation of Solution

In the below compound, negatively charged oxygen atom is in axial position where it can easily undergo intramolecular general-base reaction comparing to $O^{-}$ group in equatorial position. Here, the $O^{-}$ act as the intramolecular catalyst where it attacks the proton atom from the carbon atom that is attached to $C{H}_{2}Br$ group. Thus, $HBr$ is easily removed in the below compound due to the position of negatively charge oxygen.

  

Therefore, the compound where $HBr$ is easily removed in a basic solution is,