Acyl chlorides

Question 1

What is an acyl chloride?

Answer 1

A derivative of carboxylic acids where the OH is replaced by Cl

Question 2

How are acyl chlorides made?

Answer 2

Reacting carboxylic acid with thionyl chloride (SOCl2) —> Acyl chloride + sulfur dioxide + hydrogen chloride
Observation: fumes of HCl
CH3CH2COOH + SOCl2 —> CH3CH2COCl + SO2 + HCl

Question 3

Why should water not be present when makig acyl chlorides?

Answer 3

Because acyl chlorides are very reactive and react with water to make carboxylic acids
CH3CH2COCl + H2O —> CH3CH2COOH + HCL

Question 4

What can acyl chlorides be used to make?

Answer 4

They are excellent chemicals for organic synthesis.
- Esters, especially phenyl esters which can’t be made using carboxylic acids.
- Carboxylic acids
- Primary and Secondary amides

Question 5

How do acyl chlorides make primary amides?

Answer 5

Acyl chloride + ammonia —> primary amide and HCl

Question 6

How do acyl chlorides make secondary amides?

Answer 6

Acyl chloride + amine —> secondary amide + hydrogen chloride