Acetal

Acetal

An acetal is a functional group with the connectivity R2C(OR')2). Here, the R groups can be organic fragments (a carbon atom, with arbitrary other atoms attached to that) or hydrogen, while the R' groups must be organic fragments not hydrogen. Dimethoxymethane is an acetal compound. Acetal is also a common name for the compound 1,1-diethoxyethane. The compound polyoxymethylene (POM) is a plastic that is also called simply "acetal" or "polyacetal." Formation of an acetal occurs when the hydroxyl group of a hemiacetal becomes protonated and is lost as water. The carbocation that is produced is then rapidly attacked by a molecule of alcohol. Loss of the proton from the attached alcohol gives the acetal.

Acetals are organic compounds classified as diether products. They are formed when an aldehyde or ketone reacts with alcohol in the presence of an acid catalyst. There are a lot of terms to digest in this description: aldehyde, ketone, and acid catalyst. A cyclic acetal is an acetal in the molecule of which the acetal carbon and one or both oxygen atoms thereon are members of a ring. see also cyclic ketal.