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How does the Cannizzaro reaction change aromatic aldehydes without alpha hydrogens?

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oxidation of alcohols — aldehyde Alcohols may be oxidized to give aldehydes, ketones, and carboxylic acids. The oxidation of organic compounds generally increases the number of bonds from carbon to oxygen, and it may decrease the number of bonds to hydrogen.

The Cannizzaro reaction is a specific type of oxidation-reduction reaction that occurs when aldehydes lacking an alpha-hydrogen—such as aromatic aldehydes—are treated with a strong base, such as sodium hydroxide.2

In this process, the aldehyde undergoes a disproportionation where half of the molecules are oxidized and the other half are reduced. Specifically, one molecule of the aldehyde is reduced to the corresponding primary alcohol, while another molecule is oxidized to the salt of the corresponding carboxylic acid. Following acidification, the final products are a primary alcohol and a carboxylic acid, represented by the general equation: $2 R C H O \to R C O O H + R C H_{2} O H$ .12