The relative reactivities of acyl compound towards nucleophilic substitution are in the order of

Options

A. acyl chloride gt acid anhydride gt ester gt amide
B. ester gt acyl chloride gt amide gt acid anhydride
C. acid anhydride gt amide gt ester gt acyl chloride
D. acyl chloride gt ester gt acid anhydride gt amide

Answer

A

Explanation

In acyl compounds (i.e. acyl chloride , acid anhydride , ester and amide ) RCO-group is same, thus reactivity depends upon the nature of group Z (i.e. `Cl^-` , `RCOO^-`, `R'O^-` , `NH_2^-`, etc)
if group Z is a weak base, then it is a strong leaving agent and its reactivity towards nucleophilic substitution is high.
The order of basic nature of Z group is
`Cl^(-) lt RCOO^(-) lt R'O^(-) lt NH_2^-`
Thus, order of reactivity is
`underset"Acyl chloride""RCOCl""gt" underset"Acid anhydride"((RCO)_2O) gt underset"Ester"(RCOO R') gt underset("Amide")(RCONH_2)`