Cannizzaro Reaction Is Not Given By: Overview of the Process

The Cannizzaro reaction is an important organic reaction used in chemical synthesis. It is an aldehyde-alcohol condensation reaction which results in the formation of a new carbon-carbon bond. It is named after Italian chemist Stanislao Cannizzaro, who first reported the reaction in 1853. The reaction is of particular interest because it involves a very simple starting material and produces a product that is useful in chemical synthesis. The Cannizzaro reaction is a nucleophilic substitution reaction between an aldehyde and an alcohol. The aldehyde acts as a nucleophile and attacks the electrophilic carbon of the alcohol. This reaction results in the formation of a new carbon-carbon bond, which can be used in further reactions. The reaction is usually carried out in aqueous or alcoholic solvents, and the reaction rate is greatly influenced by the presence of a base.

Reaction Mechanism of the Cannizzaro Reaction

The Cannizzaro reaction mechanism involves the nucleophilic attack of the aldehyde on the electrophilic carbon of the alcohol, followed by the formation of a new carbon-carbon bond. The reaction proceeds in two steps. In the first step, the aldehyde attacks the electrophilic carbon of the alcohol, forming an intermediate species known as a hydrate. This hydrate then undergoes a rearrangement and the new carbon-carbon bond is formed. The reaction mechanism of the Cannizzaro reaction is illustrated in Figure 1. The aldehyde attacks the electrophilic carbon of the alcohol, forming a hydrate intermediate. This intermediate then undergoes a rearrangement, forming a new carbon-carbon bond. This new bond is then stabilized by the addition of a base, which deprotonates the hydrate. The resulting product is a new carbon-carbon bond, which can be further reacted in other synthesis reactions.

What the Cannizzaro Reaction Is Not Given By

The Cannizzaro reaction is not given by some starting materials. These include ketones, carboxylic acids, and amines. These compounds do not contain an electrophilic carbon, so they cannot undergo the nucleophilic substitution reaction of the Cannizzaro reaction. Additionally, the reaction does not work with enols, which contain an oxygen atom in place of the carbon atom. The Cannizzaro reaction also does not work with enolates. Enolates are carboxylic acid derivatives that have an anion attached to the oxygen atom. These compounds cannot undergo the nucleophilic substitution reaction of the Cannizzaro reaction because the anion prevents the formation of the hydrate intermediate.

Conclusion:

The Cannizzaro reaction is an important organic reaction which is used in many types of chemical synthesis. It is a nucleophilic substitution reaction between an aldehyde and an alcohol which results in the formation of a new carbon-carbon bond. However, this reaction is not given by some starting materials, such as ketones, carboxylic acids, amines, enols, and enolates. Understanding the limitations of the Cannizzaro reaction is important for successful synthesis.