Question

Propose a mechanism for the reaction of an acyl chloride with acetate ion to form an acid anhydride

Short answer

Mechanism followed as:

Step-by-step solution

Reaction of acyl chloride with acetate

It’s the reaction used for the formation of acidic anhydride on the reaction of the acyl chloride with sodium acetate followed by the removal of the sodium from sodium acetate and the chloride from acyl chloride the acetic anhydride formed.

Mechanism

Mechanism followed as:

1. Removal of the sodium from the sodium acetate

2. The acetate oxygen on reaction with acyl carbonyl so the electron density shifted to carbonyl oxygen having a negative charge.

3. Again the electron density comes back from oxygen and again the carbonyl formation occurs and the leaving the chloride ion to occur

4. Acetic anhydride formation occur