Conversion to carboxylic acids [H2O]
Conversion to carboxylic acids [H2O] Definition:
Treatment of acid chlorides with water leads to the formation of carboxylic acids. This is called hydrolysis of acid chlorides.
Conversion to carboxylic acids [H2O] Explained:
Acid chlorides react with water, often violently, to give the corresponding carboxylic acids and hydrogen chloride as a by-product. This by-product can often produce an undesired reaction, so the pyridine is used to convert the hydrogen chloride into pyridinium chloride (unreactive form). This is a simple example of addition-elimination reaction.
The mechanism of this transformation consists of three steps. In the first step, water function as a nucleophile and attacks the carbonyl carbon. In the second step, the carbonyl group is re-formed by expelling a chloride ion which is a good leaving group. And in the last step, the positive charge of the oxygen is removed by protonation and the carboxylic acid is formed.