Ester Reactions: Acid-Catalyzed Hydrolysis - Online Tutor, Practice Problems & Exam Prep

Acid-catalyzed hydrolysis of esters involves breaking an ester bond using water in an acidic medium, typically with an H⁺ catalyst. This reaction produces a carboxylic acid and an alcohol. The carbonyl carbon of the ester gains a hydroxyl group (–OH), transforming into a carboxylic acid, while the oxygen from the ester linkage acquires a hydrogen atom, forming an alcohol. Understanding this process is crucial for grasping esterification and hydrolysis reactions in organic chemistry.

Acid-Catalyzed Ester Hydrolysis Concept 1

Hey, everyone. So in this video, we're going to take a look at acid catalyzed hydrolysis of esters. Now under this reaction, an ester is hydrolyzed into a carboxylic acid and an alcohol in an acidic medium. Now when we say hydrolyzed and we say a hydrolysis reaction, well, this just means a reaction that breaks out a molecule through a reaction with water. And the basic idea of this reaction is that if we take a look here at this general reaction here, we have our ester bond here, this blue part here, and water with the use of an acid catalyst in the form of H⁺, it's going to be used to cut this ester bond. As a result of this, the carbonyl carbon gains an OH. So here our carbonyl carbon gains an OH and it becomes a carboxylic acid, and then the oxygen which was part of the ester linkage will gain 1 hydrogen atom. This helps to create it into an alcohol. So the basic idea of this reaction is that we have an ester and through the use of water and an acid catalyst, we help to create a carboxylic acid and an alcohol as our two products.

Acid-Catalyzed Ester Hydrolysis Example 1

Draw skeletal formulas for the products of the following reaction. So here we have our ester, and we're using water with h+ as a catalyst. Now remember, the premise of this reaction is we're going to cut the ester bond here. As a result of this, the carbonyl carbon here will gain an OH group to become a carboxylic acid, and then we're going to say that oxygen here will gain a hydrogen and create an alcohol. So in this acid-catalyzed hydrolysis, we have our ester being transformed into a carboxylic acid and an alcohol as our two products.

Write a common name for the carboxylic acid produced in the following reaction.

• A. Oxalic acid
• B. Valeric acid
• C. Butyric acid
• D. Malonic acid

Here’s what students ask on this topic:

What is acid-catalyzed hydrolysis of esters?

Acid-catalyzed hydrolysis of esters is a chemical reaction where an ester is broken down into a carboxylic acid and an alcohol in the presence of water and an acid catalyst, typically H⁺. The reaction involves the ester bond being cleaved, with the carbonyl carbon gaining a hydroxyl group (–OH) to form a carboxylic acid, and the oxygen from the ester linkage acquiring a hydrogen atom to form an alcohol. This process is essential for understanding esterification and hydrolysis reactions in organic chemistry.

What are the products of acid-catalyzed hydrolysis of esters?

The products of acid-catalyzed hydrolysis of esters are a carboxylic acid and an alcohol. During the reaction, the ester bond is broken, and the carbonyl carbon of the ester gains a hydroxyl group (–OH), transforming into a carboxylic acid. Simultaneously, the oxygen from the ester linkage acquires a hydrogen atom, forming an alcohol. This reaction is facilitated by the presence of water and an acid catalyst, typically H⁺.

How does the acid catalyst function in the hydrolysis of esters?

The acid catalyst, typically H⁺, functions by protonating the carbonyl oxygen of the ester, making the carbonyl carbon more electrophilic and susceptible to nucleophilic attack by water. This protonation step is crucial as it facilitates the cleavage of the ester bond. The acid catalyst also helps stabilize the transition state and intermediates during the reaction, ensuring the efficient conversion of the ester into a carboxylic acid and an alcohol.

Why is water necessary in the acid-catalyzed hydrolysis of esters?

Water is necessary in the acid-catalyzed hydrolysis of esters because it acts as the nucleophile that attacks the electrophilic carbonyl carbon of the ester. This attack leads to the cleavage of the ester bond. The water molecule provides the hydroxyl group (–OH) that attaches to the carbonyl carbon, forming a carboxylic acid, and the hydrogen atom that attaches to the oxygen from the ester linkage, forming an alcohol. Without water, the hydrolysis reaction cannot proceed.

What is the role of the carbonyl carbon in the hydrolysis of esters?

The carbonyl carbon in the hydrolysis of esters plays a crucial role as the electrophilic center that is attacked by the nucleophile, which is water in this case. During the reaction, the carbonyl carbon is protonated by the acid catalyst, making it more susceptible to nucleophilic attack. Once attacked by water, the carbonyl carbon undergoes a series of transformations, ultimately gaining a hydroxyl group (–OH) and converting into a carboxylic acid. This step is essential for the cleavage of the ester bond and the formation of the reaction products.