Conversion of acid chlorides to esters through addition of an alcohol
Description: Acid chlorides are converted to esters when treated with alcohols.
Notes: Base is sometimes added to neutralize the HCl that is formed in this reaction.
The third example is an intramolecular reaction – make sure you can see this.
1,2-addition of alcohol to the acid chloride (Step 1, arrows A and B) results in an anion, which is then protonated (Step 2, arrows C and D). Elimination of chloride ion (Step 3, arrows D and F) results in a positively charged ester, which is then deprotonated (Step 4, arrows G and H).
- The reaction is considerably faster when base is added to remove the HCl that is formed.
- There are other reasonable ways to show the proton transfer and deprotonation steps.