Which of the following acid will undergo thermal decomposition (decarboxylation) through enol intermediate

Options

A.
B.
C.
D.

Answer

B,C,D

Explanation

(B,C,D) Decarboxyation is facilaitated by the presence of any carbonyl group at the `beta` -position, including that of carboxyl group or ester. The mechanism followed through a cyclic, six members transition state involving rearrangements of three electron pairs gives the enol of a carboxylic acid, which is tautomerised to the carboxylic acid.