Question

Arrange the following carbonyl compounds in the decreasing order of their reactivity towards nucleophilic addition reaction:
(A) CH₃CHO
(B) HCHO
(C) Cl₃CCHO
(D) CH₃COCH₂CH₃
Choose the correct answer from the options given below:

• A. A >B >C >D
• B. B >A>D>C
• C. B >C >A>D
• D. C >B >A>D

Hint:

Electron-withdrawing groups such as Cl reduce nucleophilic attack, making compounds like CHO less reactive.

Answer 1

The Correct Option is C

The reactivity of carbonyl compounds towards nucleophilic addition is influenced by the electron-withdrawing or electron-donating groups attached. More reactive compounds are those with fewer electron-withdrawing groups. Thus, the order of reactivity is:

B (HCHO) has the highest reactivity.

C (Cl₃CHO) follows due to the electron-withdrawing effect of the -Cl groups.

A (CH₃CHO) is less reactive compared to C.

D (CH₃COCH₂CH₃) is the least reactive due to the bulky group.