Acetal

This article is about type of chemical. For polymer sometimes called "acetal", see polyoxymethylene.

General shape of acetals.

An acetal is a type of organic compound where two ether functional groups share one carbon atom. A ketal is an acetal that has no hydrogen atoms on the shared carbon.

Acetals are commonly used as protecting groups for carbonyl compounds. A typical example is the reaction of a ketone with ethylene glycol or trimethylene glycol to make a dioxolane or dioxane.