Question

The ease of hydrolysis in the compounds $CH _{3} COCl ( I ), CH _{3}- CO - O - COCH _{3}( II )$ $CH _{3} COOC _{2} H _{5}( III )$ and $CH _{3} CONH _{2}( IV )$ is of the order

• A. I > II > III > IV
• B. IV > III > II > I
• C. I > II > IV > III
• D. II > I > IV > III

Answer 1

Answer: (A)

I > II > III > IV

Answer 2

The ease of hydrolysis of carbonyl compounds depend on the group attached to the carbonyl carbon. Among the given options, chlorine $(- Cl )$ group is electron withdrawing group which makes the carbonyl group electrophilic. Hence, hydrolysis can occur most easily. The order for electron withdrawing tendency among given options is as follows:

$- Cl >- OCOCH _{3}>\,- OC _{2} H _{5}>\,- NH _{2}$

So, the correct order for the ease of hydrolysis in the given compounds is as follows:

$\underset{I}{CH_3COCl}>\, \underset{II}{CH_3COOCOCH_3}>\, \underset{III}{CH_3COOC_2H_5}>\, \underset{IV}{CH_3CONH_2}$