19.9: Carboxylic Acid Derivatives: Esters

Fischer esterification is the esterification of a Carboxylic acid by heating it with an alcohol in the presence of a strong acid as the catalyst.

Going from reactants to products simplified

Example

Mechanism

The overall reaction is reversible; to drive the reaction to completion, it is necessary to exploit Le Châteliers principle, which can be done either by continuously removing the water formed from the system or by using a large excess of the alcohol.

1) Protonation of the carbonyl by the acid. The carbonyl is now activated toward nucleophilic attack.

2) Nucleophilic attack on the carbonyl

3) Proton transfer

4) Water leaves

5) Deprotonation

Contributors

• Prof. Steven Farmer (Sonoma State University)