Question

16. Aldehydes are generally more reactive than ketones in nucleophilic addition reaction due to
steric and electric reasons. Sterically, the presence of two relatively large substituents in
ketones hinders the approach of nucleophile to carbonyl carbon than in Aldehydes having
only on such substituent. Electronically, Aldehydes are more reactive than ketones because
two alkyl groups reduce the electrophilicity of the carbonyl carbon more effectively than in
former
4x1M=4M
(i) Aldol condensation would not occur in:
a) CH,COCH,
b) CHÚCH,CHO
c) HCHO
d) CH,CHO
(ii) Cannizzaro reaction occurs with
a) CH -CH,OH b) C, H,CHO c) CH,CHO
d) CH-CO-CH,
(iii) Which of the following compound will show positive silver mirror test?
a) HCOOH b) CH(CHOH),CHO c) CH,CO(CHOH)CH, d) Both (a) and (b)
(iv) Aldehydes and ketones are distinguished by which of the following test?
a) Lucas test b) Tollen's test c) KMnO, solution (Baryer's test) d) none of these
(OR)
(V) In Which reaction, >C=0 can be reduced to >CH?
a) Wolf - Kishner reaction
b) Reimer - Tiemann reaction
c) Wurtz reaction
d) None of these​

Answer 1

Answer:

Aldehydes are generally more reactive than ketones in nucleophilic addition reactions due to steric and electronic reasons.

Sterically, the presence of two relatively large substituents in ketones hinders the approach of nucleophile to carbonyl carbon than in aldehydes having only one such substituent.

Electronically, two alkyl groups reduce the electrophilicity of the carbonyl carbon more effectively in ketones than in aldehyde.

Hence Aldehydes are more reactive toward nucleophilic addition reactions than Ketones.