The relative reactivities of acyl compounds towards nucleophilic substitution are in the order of
1) Acid anhydride > Amide > Ester > Acyl chloride
2) Acyl chloride > Acid anhydride > Ester > Amide
3) Ester > Acyl chloride > Amide > Acid anhydride
4) Acyl chloride > Ester > Acid anhydride > Amide
2) Acyl chloride > Acid anhydride > Ester > Amide