Dicarboxylic acid

Dicarboxylic acids are organic compounds that are substituted with two carboxylic acid functional groups. In molecular formulae for dicarboxylic acids, these groups are often written as HOOC-R-COOH, where R is usually an alkyl, alkenyl, or akynyl group. Dicarboxylic acids can be used to prepare copolymers such as nylon and polyethylene terephthalate.

In general, dicarboxylic acids show the same chemical behaviour and reactivity as monocarboxylic acids. The ionization of the second carboxyl group occurs less readily than the first one. This is because more energy is required to separate a positive hydrogen ion from the doubly charged anion than from the single charged anion.

A mnemonic to aid in remembering the order of the common nomenclature for the first six dicarboxylic acids is "Oh my, such great apple pie!" (oxalic, malonic, succinic, glutaric, adipic, pimelic).

When one of the carboxy groups is replaced with an aldehyde group, the resulting structure is called a "aldehydic acid".

Examples
See Category:Dicarboxylic acids for a list.

Dicarbonsäuren Ácido dicarboxílico Kwas dikarboksylowy Двухосновные карбоновые кислоты Dikarboksyylihappo 二聚酸