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How do cyanide ions react with aldehydes to form cyanohydrins?

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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 cyanide ion ( ${CN}^{-}$ ) acts as a carbon nucleophile that reacts with aldehydes to form cyanohydrins, which are compounds containing both a hydroxyl ( $OH$ ) group and a cyano ( $CN$ ) group on the same carbon atom.1

The reaction process typically involves the following steps:

Nucleophilic Addition: The cyanide ion attacks the carbonyl carbon of the aldehyde.1
Acidification: Following the initial addition, the reaction mixture is acidified to yield the final cyanohydrin product.1

This reaction is often facilitated by base catalysis, such as the use of sodium hydroxide, to promote the addition of hydrogen cyanide to the aldehyde. These cyanohydrins are valuable in organic chemistry, serving as important intermediates in various synthetic processes.23

It is important to note that hydrogen cyanide is an extremely poisonous substance that inhibits cellular oxidative processes; therefore, extreme caution and professional safety protocols are required when handling these chemicals.3