List the following carboxylic acid derivatives in decreasing order of reactivity in nucleophilic acyl substitution reactions: acetic anhydride, methyl acetate, acetamide, acetyl chloride.

acetyl chloride > acetic anhydride > methyl acetate > acetamide

Explanation:

Such kind of substitution reaction in which nucleophiles and the acyl compound interact is known as nucleophilic acyl substitution reaction. In this reaction, the interaction between carbonyl compounds and the nucleophile takes place by addition reaction. The reactivity of the acyl compound is based on the condition of the leaving group that is related to the acidity of the compounds. So the decreasing order of reactivity of the acyl compounds is, acetyl chloride > acetic anhydride > methyl acetate > acetamide.