Question

The increasing order of the reactivity of the following compund in nucleophilic addition reaction is : Propanal, Benzaldehyde, Propanone, Butanone

• A. $\text{Benzaldehyde < Propanal < Propanone < Butanone}$
• B. $\text{Propanal < Propanone < Butanone < Benzaldehyde}$
• C. $\text{Butanone < Propanone < Benzaldehyde < Propanal}$
• D. $\text{Benzaldehyde < Butanone < Propanone < Propanal}$

Answer 1

The correct option is C $\text{Butanone < Propanone < Benzaldehyde < Propanal}$

Aldehydes are more reactive towards nucleophilic substitution compared to ketones because of less steric hindrance and electronic factors. In Aldehydes electron withdrawing group increase its reactivity by making the carbonyl carbon more electrophilic.
Benzaldehyde is bulkier compared propanal hence, propanal is more reactive.
Comparing propanone and butanone, butanone is bulkier hence, it is less reactive compare to propanone.
Thus,
Hence, option (a) is correct.