Question

Which of the following is an example of nucleophilic addition to acetaldehyde?

• A. Acetal formation
• B. Cyanohydrin formation
• C. Bisulphite adduct
• D. All of the above

Answer 1

The correct option is D All of the above

Out of the four choices a,b and c are examples of nucleophilic addition reactions.

A nucleophilic addition reaction is an addition reaction where a chemical compound with an electron deficient or electrophilic double or triple bond, a $\pi$ bond reacts with electron-rich reactant, termed a nucleophile, with disappearence of the double bond and creation of two new single or $\sigma$ bond . With a corbonyl compound as an electrophile, the nucleophile can be:

• An alcohol in acetalisation to an acetal.
• A cyanide anion in cyanohydrin reaction forming a cyanohydrin product
• A sulfur ion from sodium bisulfite which forms a bisulfite adduct with aldehyde groups.

Hence, the correct answer is option (d).