Question

Show the mechanism of reaction of hydroxide ion with an ester in basic conditions to form an intermediate carboxylate, and acidic conditions for the intermediate to form a carboxylic acid.

Answer 1

"Mechanism of reaction of hydroxide ion with an ester in basic conditions to form an intermediate carboxyl ate: Ester hydrolysis in the presence of base is called ""Saponification"" The mechanism of ester Saponification involves the reaction of the nucleophilic hydroxide ion at the carbonyl carbon to give a tetrahedral addition intermediate from which an alkoxide ion is expelled The alkoxide ion, after expulsion as a leaving group and it reads with the acid to give carboxylate intermediate. In this reactions at the Carbonyl group protonation makes the carbonyl carbon more electrophilic \r\n Step 3: Protonation of the leaving oxygen converts it into a better leaving group. Loss of this group gives a protonated Carboxylic acid, from which a proton is removed to give the carboxylic acid itself. "