A reaction of aldehydes to give carboxylic acids and alcohols. It occurs in the presence of strong bases with aldehydes that do not have alpha hydrogen atoms. For example, benzenecarbaldehyde gives benzenecarboxylic acid and benzyl alcohol:2C6H5CHO → C6H5COOH+C6H5CH2OH Aldehydes that have alpha hydrogen atoms undergo the aldol reaction instead. The Cannizzaro reaction is an example of a disproportionation. It was discovered by Stanislao Cannizzaro.
2C6H5CHO → C6H5COOH+C6H5CH2OH