5 Other reactions
(i) Cannizzaro reaction: Aldehydes which do not have an
a-hydrogen atom, undergo self oxidation and reduction
(disproportionation) reaction on heating with concentrated alkali In this reaction, one molecule of the aldehyde is reduced to
alcohol while another is oxidised to carboxylic acid salt D
D
Rationalised 2023-24
243
Aldehydes, Ketones and Carboxylic Acids
(ii) Electrophilic substitution reaction: Aromatic aldehydes and ketones
undergo electrophilic substitution at the ring in which the carbonyl
group acts as a deactivating and meta-directing group