Hemiacetal Formation Tutorial

Acetal Formation Tutorial

Hemiacetal Formation Self Assessment Activity

Acetal Formation Self Assessment Activity

Tutorial and Self Assessment AvailableCarbonyl Addition - Loss of carbonyl oxygen

Acetal formation

Background Colour:

Click the structures and reaction arrows in sequence to view the 3D models and animations respectively

A solution of acetaldehyde in methanol reacts to form a hemiacetal, but if catalytic acid is added to the mixture, not only does the rate of reaction increase but another product is formed. This product is an 'acetal'. In the presence of acid, hemiacetals can undergo an elimination reaction, losing the oxygen atom that once belonged to the parent aldehyde's carbonyl group of the hemiacetal. The two stages in the formation of acetal are shown.