Question

Out of p-tolualdehyde and p-nitrobenzaldehyde, which one is more reactive towards nucleophilic addition reactions, why?

Answer 1

P-nitrobenzaldehyde is more reactive towards the nucleophilic addition reaction than p- tolualdehyde as Nitro group is electron withdrawing in nature. Presence of nitro group decrease electron density, hence facilitates the attack of nucleophile. The presence of \[\ce{-CH3}\] leads to +I effect as \[\ce{-CH3}\] is electron releasing group.