Question

Maximum decarboxylation occurs in:

• A. $C{H}_{3}COOH$
• B. $C_6{H}_{5}COOH$
• C. $C_6{H}_{5}C{H}_{2}COOH$
• D. $C{H}_{3}COC{H}_{2}COOH$

Answer 1

The correct option is D $C{H}_{3}COC{H}_{2}COOH$

In decarboxylation reaction intermediate formed is carbanion.

Rate of decaboxylation $\propto$ Stability of carbanion
In option (d) $\beta -\text{keto acid}$ undergoes decarboxylation readily due to stable 6 membered transition state (T.S) formation Also, the enolate ion formed is resonance stabilized