Difference Between Malonic Acid and Succinic Acid

The key difference between malonic acid and succinic acid is that malonic acid structure has one carbon atom between two carboxylic acid functional groups, whereas succinic acid has two carbon atoms between the two carboxylic acid groups.

Both malonic acid and succinic acid are dicarboxylic acids. This means these compounds contain two carboxylic acid functional groups per one molecule.

CONTENTS

1. Overview and Key Difference
2. What is Malonic Acid
3. What is Succinic Acid 
4. Malonic Acid vs Succinic Acid in Tabular Form
5. Summary – Malonic Acid vs Succinic Acid

What is Malonic Acid?

Malonic acid is an organic compound, and it is a simple dicarboxylic acid. The IUPAC name of this compound is propanedioic acid. The chemical formula of this compound is CH2(COOH)2. The molar mass of this substance is 104.06 g/mol. There are ionized forms of malonic acid as well as esters and salts that are collectively named malonates.

Figure 01: The Chemical Structure of Malonic Acid

This acidic substance is naturally occurring in many foods such as fruits and vegetables. Typically, citrus fruits grown in farms contain higher levels of malonic acid than that are grown through conventional agriculture. This acid was first discovered by the French chemist Victor Dessaignes in 1858 through the oxidation of malic acid. We can easily determine the structure of malonic acid through X-ray crystallography.

Figure 02: The Preparation Process of Malonic Acid

Classically, we can prepare malonic acid using chloroacetic acid as a starter. We need sodium carbonate and sodium cyanide as reactants. First, the sodium carbonate generates the sodium salt of chloroacetic acid, which then reacts with sodium cyanide giving the sodium salt of cyanoacetic acid. This reaction occurs via nucleophilic substitution. Thereafter, the nitrile group undergoes hydrolysis along with sodium hydroxide, forming sodium malonate. We can get malonic acid from this resulting substance through acidification.

What is Succinic Acid?

Succinic acid is a dicarboxylic acid compound having the chemical formula (CH2)2(COOH)2. This compound has two carbon atoms separating the carboxylic acid functional groups. The name of this compound comes from the Latin name succinum, which refers to the “amber.”  Generally, this substance occurs in its anionic form when it is in living organisms. This anionic state is named succinate. This anion has many biological applications as a metabolic intermediate which tends to convert into fumarate through the succinate dehydrogenase enzyme activity during the electron transport chain. This process is involved in the production of ATP.

Figure 03: The Chemical Structure of Succinic Acid

Succinic acid appears as a white, odorless solid substance having a highly acidic taste. When it is in an aqueous solution, succinic acid tends to ionize, forming its conjugate base, the succinate ion. This is a diprotic acid, giving two protons to the solution.

When considering the commercial-scale production of succinic acid, common routes include hydrogenation of maleic acid, oxidation of 1,4-butanediol, and carbonylation of ethylene glycol. However, we can also produce succinate using butane and maleic anhydride. Historically, people obtain this acidic substance from amber through the distillation to get the amber spirit.

What is the Difference Between Malonic Acid and Succinic Acid?

Both malonic acid and succinic acid are dicarboxylic acids. That means both these compounds contain two carboxylic acid functional groups per one molecule. The key difference between malonic acid and succinic acid is that malonic acid structure has one carbon atom between two carboxylic acid functional groups, whereas succinic acid has two carbon atoms between the two carboxylic acid groups.

The following infographic presents the difference between malonic acid and succinic acid in tabular form.

Summary – Malonic Acid vs Succinic Acid

Malonic acid and succinic acid are dicarboxylic acids. This means both these compounds contain two carboxylic acid functional groups per one molecule. The key difference between malonic acid and succinic acid is that malonic acid structure has one carbon atom between two carboxylic acid functional groups, whereas succinic acid has two carbon atoms between the two carboxylic acid groups.