Question 29.SE.3: Name each of the following esters and indicate the products ...
Name each of the following esters and indicate the products of their reaction with aqueous base.
(a) 
(b) 
Analyze We are asked to name each ester and to determine their saponification products.
Plan To name an ester, we must analyze its structure and determine the identities of the alcohol and acid from which it is formed. Identifying these two components will also allow us to determine the products of the saponification.
Solve Esters are formed by the condensation reaction between an alcohol and a carboxylic acid. We can identify the alcohol by adding an OH to the alkyl group attached to the O atom of the carboxyl (COO) group. We can identify the acid by adding an H group to the O atom of the carboxyl group. We’ve learned that the first part of an ester name indicates the alcohol portion and the second part indicates the acid portion. The name conforms to how the ester undergoes hydrolysis, reacting with base to form an alcohol and a carboxylate anion.
(a) This ester is derived from ethanol (CH_3CH_2OH) and benzoic acid (C_6H_5COOH).Its name is therefore ethyl benzoate. The net ionic equation for reaction of ethyl benzoate with hydroxide ion is:
The products are benzoate ion and ethanol.
(b) This ester is derived from phenol (C_6H_5OH) and butanoic acid (CH_3CH_2CH_2COOH). The residue from the phenol is called the phenyl group. The ester is therefore named phenyl butanoate. The net ionic equation for the reaction of phenyl butanoate with hydroxide ion is
The products are butanoate ion and phenoxide ion.