Provide an example of the aldehyde and hydroxide in the Cannizzaro reaction.

The aldehyde and hydroxide in the Cannizzaro reaction are formaldehyde and hydroxide ion, respectively.

The Cannizzaro reaction is a redox reaction that involves the oxidation of one molecule of aldehyde and the reduction of another molecule of the same aldehyde. The reaction is typically carried out in the presence of a strong base, such as hydroxide ion, which acts as a nucleophile and attacks the carbonyl carbon of the aldehyde. The resulting intermediate is a tetrahedral intermediate, which then undergoes either oxidation or reduction, depending on the conditions of the reaction.

In the case of formaldehyde, which is the simplest aldehyde, the reaction proceeds as follows:

HCHO + OH- → HCOO- + H2O

In this reaction, formaldehyde is oxidized to formate ion, while another molecule of formaldehyde is reduced to methanol. The overall reaction is a disproportionation reaction, as it involves the conversion of one molecule of aldehyde into both an oxidized and a reduced product.

The Cannizzaro reaction is an important reaction in organic chemistry, as it provides a means of synthesizing alcohols from aldehydes, and is also used in the production of various chemicals and pharmaceuticals. Understanding the mechanism of the reaction and the role of the aldehyde and hydroxide ion is essential for students studying organic chemistry.