Acetal Definition

This is the general structure of an acetal compound.
This is the general structure of an acetal compound. Todd Helmenstine
by Anne Marie Helmenstine, Ph.D.
Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels.
Updated March 08, 2017

Definition: An acetal is an organic molecule where two separate oxygen atoms are single bonded to a central carbon atom.

Acetals have the general structure of R2C(OR')2.

An older definition of acetal had one at least one R group as a derivative of an aldehyde where R = H, but an acetal can contain derivatives of ketones where neither R group is a hydrogen. This type of acetal is called a ketal.

Acetals that contain different R' groups are called mixed acetals.

Acetal is also a common name for the compound 1,1-diethoxyethane.

Examples: Dimethoxymethane is an acetal compound.