Question

The correct stability order of the anions formed due to the deprotonation of the following molecules is:

• A. III > IV > II > I
• B. IV > III > I > II
• C. III > II > I > IV
• D. II > III > IV > I

Answer 1

The correct option is A III > IV > II > I

The carbanions formed after the deprotonation,respectively, are:

Structure III and IV carboxylate ions are more stable than the structure I and structure II phenoxides ions because of the delocalisation of negative charge on $O$ with the $C=O$ bond in structure III and IV.
The $-I$ effect of $-Cl$ makes the carboxylate ion of structure II more stable than that of structure I.
On the other hand, the hyperconjugation effect of the $-C{H}_3$ group makes the carboxylate ion of structure IV less stable than that of structure III.

Therefore, the correct order of the carboxylate ion stability is:
III > IV > II > I