Chapter 6, Problem 6.79P

Interpretation Introduction

Interpretation:

It is to be explained how the ${\text{pK}}_{\text{a}}$ value of a typical ketone (acetone ${\text{pK}}_{\text{a}}\text{ = 20}$) is lower than that of a typical ester (ethylacetate ${\text{pK}}_{\text{a}}\text{ = 25}$).

Concept introduction:

The ${\text{pK}}_{\text{a}}$ value decreases with an increase in the strength of the acid. The acid whose conjugate base is most stable is the stronger acid. The electron donating group increases the electron density at the carbonyl group and reduces its electron withdrawing effect.